The American Journal of Orthopedics

The ulnar collateral ligament (UCL) is the primary restraint to valgus stress between 20° and 125° of motion.^1-5 Overhead athletes, most commonly baseball pitchers, are at risk of developing UCL insufficiency, and dysfunction presents as pain with loss of velocity and control. Some injuries may present acutely while throwing, but many patients, when questioned, report a preceding period of either pain or loss of velocity and control.

Authors have documented a significant rise in elbow injuries in young athletes, especially pitchers.⁶ Extended seasons, higher pitch counts, year-round pitching, pitching while fatigued, and pitching for multiple teams are risk factors for elbow injuries.⁷ Pitchers in the southern United States are more likely to undergo UCL reconstruction than those from the northern states.⁸ Pitchers who also play catcher are at a higher risk due to more total throws than those who pitch and play other positions or pitch only. Throwers with higher velocity are more likely to pitch in showcases, pitch for multiple teams, and pitch with pain and fatigue, and these are all risk factors.⁶ Also, in one study of youth baseball injuries, individuals in the injured group were found to be taller and heavier than those in the uninjured group.⁶ Pitch counts, rest from pitching during the off-season, adequate rest, and ensuring pain-free pitching can lessen the risk of injury.⁶ As expected with the rise in throwing injuries, the rise in medial elbow procedures has risen.⁹

While throwing, stress across the medial elbow has been measured to be nearly 300 N. A maximum varus force during pitching was measured to be 64 N-m at 95° ± 14°.¹⁰ Morrey and An⁴ determined that the UCL generated 54% of the varus force at 90° of flexion. During active pitching, this value is likely reduced due to simultaneous muscle contraction, but if one assumes the UCL bears 54% of the maximal load, the UCL must be able to withstand 34 N-m. The UCL can withstand a maximum valgus torque between 22.7 and 34 N-m^11-13; therefore, during pitching, the UCL is at or above its failure load. After thousands of cycles over many years, one can imagine how the UCL might be injured.

Multiple techniques have been proposed in the surgical treatment of UCL injuries. Jobe¹⁴ pioneered UCL reconstruction in 1974 in Tommy John, a Major League Baseball pitcher. John returned to pitch successfully, and both the UCL and the reconstruction are commonly called by his name. Jobe¹⁴ reported his technique in 1986, and it has remained, with a few modifications, the primary method for reconstruction of the UCL (Figure 1).

Primary repair has been reported, and the best results have been in younger pitchers with acute injuries.¹⁵ Cain and colleagues¹⁶ reported a 70% return to same or higher level with repair alone, which was an improvement on Azar’s series¹⁷ with 63% return to same or higher level. Recent advancements have included primary repair with augmentation using grafts or anchored suture or tape¹⁸ (Figure 2).

The modified Jobe and docking techniques remain the most commonly used techniques with reproducible and reliable results.^19,20

Evaluation

A standard evaluation with physical examination and imaging is completed in all throwers with elbow pain. In our prior study,¹⁶ we found that 100% of patients experienced pain during athletic activity and that 96% of throwers complained of pain during late cocking and acceleration phases of the throwing motion. Nearly half reported an acute onset of pain, while 53% were unable to identify a single inciting event. Seventy-five percent of the acute injuries were during competition. Delayed diagnosis was very common, with an average time to diagnosis after onset of symptoms of 6.4 months. Neurologic symptoms were seen in 23% of athletes, most of which were ulnar nerve paresthesias during throwing.¹⁶

Physical examination includes inspection for swelling, hand intrinsic atrophy, neurovascular examination, range of motion, shoulder examination, and elbow stress examination. Range of motion at presentation averaged 5° to 135° with 85° of supination and pronation.¹⁶ All patients need neurologic evaluation for ulnar nerve dysfunction. Tinel test of the cubital tunnel was positive in 21%.¹⁶ Significant ulnar nerve dysfunction, including hand weakness, is much less common but must be well examined and documented. The shoulder must also be evaluated for loss of rotation, which can lead to increased stress on the elbow. An evaluation of mechanics may point out flaws in technique, which may be contributing to elbow stress. The UCL stress examination includes static stress at 30° of flexion, the milking test at 90°, and the moving valgus stress test. The presence of pain directly over the UCL or laxity compared to the uninvolved side is suggestive of UCL injury.

Radiographic evaluation is completed in all patients with concern for UCL injury. Standard x-rays of the elbow, including anteroposterior, medial, and lateral obliques, axial olecranon, and lateral views, are obtained to evaluate bony abnormalities. Fifty-seven percent of our series showed some abnormality, most commonly olecranon osteophyte formation or ectopic calcification within the UCL substance. Stress radiography rarely changed the treatment course and is somewhat difficult to interpret because of the reports documenting normal increased medial elbow opening in the dominant arm of throwing athletes.²¹ Magnetic resonance imaging (MRI) is obtained very commonly in this patient population, and intra-articular contrast is crucial. Partial, undersurface tears are common, and a contrasted study better demonstrates undersurface tears or avulsions. The T-sign as described by Timmerman and colleagues²² using computed tomography (CT) arthrography shows partial undersurface detachment, which can be difficult to see without intra-articular contrast.²² This finding is very well visualized on MRI arthrogram as well (Figure 3).

Sensitivity in partial tears is also highly favorable for CT arthrogram over noncontrasted MRI, detecting 71% vs 14%.²² MRI with arthrogram provides further detail to better detect tears and to determine the condition of the ligament, and is currently the gold standard diagnostic test for UCL evaluation.

 

Nonoperative Management

Nonoperative treatment is recommended for 3 months prior to performing reconstruction. Patients are given complete rest from throwing, but rehabilitation is initiated immediately. Rehabilitation exercises and nonsteroidal anti-inflammatory medications are prescribed, and activities that place valgus stress across the elbow are avoided. After resolution of symptoms, an interval throwing program is initiated, and the athlete is gradually returned to sport. Unfortunately, due to season-specific schedules and time-sensitive demands in high-level throwers, operative treatment is often chosen without an extended period of conservative treatment.

Platelet-rich plasma (PRP) therapy has recently been shown to improve healing rates and promote healing in partial UCL tears,²³ and as orthobiologics are advanced, they will likely play a larger role in the treatment of UCL injuries.

Surgical Technique

At our institution, UCL reconstruction is performed with the modified Jobe technique as described by Azar and colleagues.¹⁷ Arthroscopy prior to reconstruction was routinely performed at our institution until we recognized that arthroscopy rarely changed the preoperative plan.¹⁶ Currently, the presence of anterior pathology such as loose bodies or osteochondral defect is our only indication for arthroscopy before reconstruction.

Ipsilateral palmaris autograft is our current graft of choice. This must be examined preoperatively because 16% of patients have unilateral absence and 9% have bilateral absence.²⁴ In revision cases or in patients with insufficient or absent palmaris, contralateral palmaris followed by contralateral gracilis tendon is used. The contralateral gracilis is chosen because of ease of setup and position of the surgeon during the harvest. Gracilis tendon is also used in cases with bony involvement of the ligament based on the results from Dugas and colleagues.²⁵ Toe extensors, plantaris, and patellar tendon grafts have also been used. One recent study showed that neither graft choice nor diameter affected resistance to valgus stress, and that all reconstruction types restored strength at 60° to 120° of flexion.²⁶

Ulnar nerve transposition is performed in all cases regardless of the presence of preoperative nerve symptoms. A complete decompression is completed proximally to the Arcade of Struthers and distally to the deep portion of the flexor carpi ulnaris. A single fascial sling of medial intermuscular septum originating from the epicondylar attachment is used to stabilize the nerve without compression. At wound closure, the deep fascia on the posterior skin flap is also sewn into the cubital tunnel to prevent the nerve from subluxating back into the groove. A single suture is placed distally closing the muscle fascia to prevent propagation of the fascial incision, which can lead to herniation. Transposition is necessary because of the ulnar nerve exposure required in the modified Jobe technique to allow elevation of the deep flexor muscle mass for ligament exposure.

The reconstruction is completed as described by Jobe¹⁴ but with a few modifications as described by Azar and colleagues¹⁷ and slight adaptations implemented since that time. The flexor-pronator mass is retracted laterally instead of detachment or splitting as described by Thompson and colleagues.²⁷ A subcutaneous rather than a submuscular ulnar nerve transposition is used.

The patient is positioned supine using an arm board. If gracilis tendon is chosen, the contralateral leg is prepped and draped simultaneously. A tourniquet is inflated after exsanguination. A medial approach is performed, and the medial antebrachial nerve is located and protected. The ulnar nerve is then located in the cubital tunnel and mobilized. The neurolysis extends to the deep portion of the flexor carpi ulnaris distally and proximally to the Arcade of Struthers, and the nerve is retracted with a vessel loop. The flexor muscle mass is not elevated from the medial epicondyle; rather, it is retracted anteriorly by small Hohmann retractors. The dissection is carried down to the UCL and found at its attachments to the medial epicondyle and sublime tubercle. If no tear is seen on the superficial surface of the ligament, a longitudinal incision is made through the ligament. Undersurface tears, partial tears, and avulsions can then be identified (Figure 4).

Often, a portion of the ligament is degenerative and is excised, leaving only healthy-appearing ligament.

The autologous graft of choice is then harvested. Our technique for palmaris harvest is performed with three 1-cm transverse incisions. The palmaris is palpated and marked with the first incision made near the distal wrist crease, and the second incision is made 3 to 4 cm proximal to the first. The tendon is found in both distal incisions and cut distally with the wrist flexed to maximize tendon length. The tendon is then pulled through the second incision and tensioned to identify the most proximal location the tendon can be palpated. A third incision is made directly over this point and carried down to cut the tendon. This usually provides a graft length of 15 to 20 cm; 13 cm is the minimum graft length to ensure good graft fixation. Muscle is removed from the tendon and each end is secured with a No. 1 nonabsorbable suture in a locking fashion.

If posterior osteophytes are present, they are removed through a posterior, vertical arthrotomy. Over-resection of the olecranon must be avoided, as this can further destabilize the elbow and place increased stress on the reconstruction. Posterior loose bodies can also be removed through this arthrotomy. The arthrotomy is then closed with absorbable suture.

Tunnel placement is critical to success. A 3.2-mm drill bit is used with palmaris grafts and a 4-mm drill bit is used with gracilis grafts. Two convergent tunnels are drilled in the medial epicondyle in a Y fashion and 2 convergent tunnels are drilled at the sublime tubercle in a U or V fashion. After drilling the first tunnel on each side, a hemostat is placed in the tunnel as an aiming point to ensure a complete tunnel is made. The junction is smoothed with a curette, leaving a 5-mm bone bridge between the articular surface and the tunnels. A bent Hewson suture passer is used to pass one end of the graft through the ulna. The 2 limbs of the tendon graft are then passed through the humeral tunnels, creating a figure-of-eight. A varus stress is applied with the elbow at roughly 30° and the 2 limbs are tied together with a No. 1 nonabsorbable suture. If enough graft remains, one or both limbs are passed back through the tunnels and secured again with No. 1 nonabsorbable suture. The 2 limbs are then tied side-to-side, incorporating the native ligament to further secure and tighten the reconstruction.

The ulnar nerve is then secured using a strip of medial intermuscular septum left intact to its insertion at the medial epicondyle. This is attached to the flexor-pronator muscle fascia with a 3-0 nonabsorbable suture. Enough length should be harvested from the septum to ensure there is no compression on the nerve. The deep posterior fascial tissue is then sewn to the periosteum of the medial epicondyle to further prevent subluxation of the nerve back into the groove. The skin is then closed in layered fashion over a superficial drain. The patient is placed in a well-padded posterior splint for 1 week, then the rehabilitation protocol is initiated as discussed below.

 

Postoperative Rehabilitation

A standardized postoperative 4-phase rehabilitation program for ulnar collateral reconstruction is followed as described by Wilk and colleagues.^28-30 The first phase begins immediately after surgery and continues for 4 weeks. During surgery, the patient’s elbow is placed in a compression dressing with a posterior splint to immobilize the elbow in 90° of flexion with wrist motion for 1 week to allow initial healing. Full range of motion of the elbow joint is restored by the end of the fifth to sixth week after surgery.

During phase II (weeks 4-10), a progressive isotonic strengthening program is initiated. Exercises are focused on scapular, rotator cuff, deltoid, and arm musculature. Shoulder range of motion and stretching exercises are performed during this phase and the Thrower’s Ten exercise program is initiated. Any adaptations or strength deficits are addressed during this phase.

During the advanced strengthening phase (phase III), from weeks 10 to 16, a sport-specific exercise/rehabilitation program is initiated. During this phase, stretching and flexibility exercises are performed to enhance strength, power, and endurance. During this phase the patient is placed on the advanced Thrower’s Ten program. Isotonic strengthening exercises are progressed, and at week 12, the athlete is allowed to begin an isotonic lifting program, including bench press, seated rowing, latissimus dorsi pull downs, triceps push downs, and biceps curls. In addition, the athlete performs specific exercises to emphasize sport-specific movements. At week 12, overhead athletes begin a 2-hand plyometric throwing program, and at 14 weeks, a 1-hand plyometric throwing program. Furthermore, endurance exercises, core stability, and leg strengthening are emphasized during phase III. Phase IV, the return to activity phase (week 16 and beyond), is characterized by the initiation of an interval throwing program. The patient is instructed to continue his stretching and strengthening program. An interval throwing program off the mound is gradually initiated at 5 to 6 months postoperative and a gradual return to competition is initiated for pitchers at 9 months and for position players 6 to 7 months postoperative.

Discussion

Results after ulnar collateral reconstruction have been good. In our series of 743 patients, 83% returned to the same or higher level at an average of 11.6 months.¹⁶ There was a 4% major complication rate and 16% minor complication rate. Major complications included medial epicondyle fracture (0.5%), significant ulnar nerve dysfunction (1 patient), rupture of graft (1%), and graft site infection. Sixteen percent of patients had ulnar nerve dysfunction, and 82% of these resolved within 6 weeks. All but 1 patient’s paresthesias resolved within 1 year.¹⁶ The 10-year follow-up of this group of patients included 256 patients and was reported by Osbahr and colleagues³¹ in 2014. Retirement from baseball was due to reasons other than the elbow in 86%, and 98% were still able to throw on at least a recreational level. The overall longevity was 3.6 years, with 2.9 years at pre-injury level or higher. Statistically, pitchers performed at a higher level after reconstruction.³¹

A recent review by Erickson and colleagues⁹ showed an overall 82% excellent and 8% good result when evaluating different techniques, including the American Sports Medicine Institute (ASMI) modification of Jobe’s technique, docking technique, and Jobe’s technique. With an overall complication rate of 10% (75% of which was transient ulnar neuritis), the procedure was deemed overall a safe surgical option. Collegiate athletes had the highest return to sport (95%) compared with high school athletes (89%) and professional athletes (86%). The docking technique had the highest rate of return to play (97%) compared with ASMI technique (93%) and Jobe technique (66%).⁹ Results after repair have not been as good as reconstruction, as reported in 2 studies.^16,32 Savoie and colleagues,¹⁵ however, reported 93% good/excellent results after primary UCL repair alone.

Another recent review of outcomes showed an overall return to same or higher level was best with docking or modified docking techniques (90.4% and 91.3%, respectively).¹⁹ Overall return with modified Jobe technique was 77%.¹⁹ O’Brien and colleagues²⁰ performed a review of 33 patients with either modified Jobe or docking technique that showed 81% return to same or higher level with modified Jobe vs 92% with docking technique. The Kerlan-Jobe Orthopaedic Clinic scores were higher in the modified Jobe group (79 vs 74) and the docking technique group returned to play nearly 1 month sooner (12.4 months vs 11.8 months).²⁰ However, comparing different techniques in a heterogenous patient population over 40 years is difficult. Many of the modified Jobe technique cases were performed in the early evolution of the rehabilitation and return-to-play programs. We believe that the current modified Jobe technique has results equal to any other variation.

Despite good results with reconstructions, the recovery is lengthy and most pitchers cannot fully return to competition level for 12 to 18 months. Extensive research has been performed in exploring alternatives to the traditional reconstruction. Advancements in orthobiologics and development of new surgical options seem to provide an alternative to reconstruction, and may allow faster return to competition with less morbidity.

PRP has been at the forefront of orthopedic research for the last 2 decades, mostly focused in tendon and bone healing. Due to the release of many inflammatory mediators, PRP is theorized to initiate a healing response with growth factors that can direct healing towards normal tissue.³³ Two main types of PRP are reported based on the presence or absence of leukocytes. PRP has been studied in many applications, but only one clinical study on the UCL has been published to date. Podesta and colleagues²³ injected PRP into the elbow of 34 baseball players with MRI-confirmed partial UCL tear. The athletes then underwent a rehabilitation program, which limited stress across the UCL. Type 1A PRP was used (leukocyte-rich, unactivated, 5x or greater platelet concentration³³). Athletes were allowed to return to sport based on symptoms and examination findings. Eighty-eight percent returned to same level of play without complaints at average 70 week follow-up, and average return to play ranged from 10 to 15 weeks.²³ No specific data were given on the 16 pitchers in the group, but with such a high rate of return, PRP needs to be further evaluated in the treatment of UCL injuries.

Another recent study from Dugas and colleagues¹⁸ presented primary UCL repair using a tape augment (InternalBrace, Arthrex). Nine matched cadaver elbows underwent UCL sectioning and then either modified Jobe reconstruction or primary repair of the UCL with placement of the InternalBrace. The biomechanical data showed the repair with internal brace to have slightly less gap, more stiffness, and higher failure strength, although these findings were not statistically significant.¹⁸ This bone-preserving technique with less exposure and healing of the native ligament may be another step towards good results with a quicker return to throwing.

 

Conclusion

UCL injuries can be disabling in throwers. Reconstruction has afforded throwers a high rate of return to preinjury function or better, and several techniques have been presented that produce acceptable results. Overall complication rates range from 10% to 15%, and the majority of complications are transient ulnar neuropraxias. Orthobiologics and repair with augmentation have more recently offered additional options that may improve success of nonoperative treatment or allow less-invasive surgical treatment. Increased involvement in youth sports and early specialization is driving injury rates in young athletes. The orthopedic community must continue to look for better ways to prevent these injuries and investigate better methods to return athletes to high-level competition.

Am J Orthop. 2016;45(7):E534-E540. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The ulnar collateral ligament (UCL) is the primary restraint to valgus stress between 20° and 125° of motion.^1-5 Overhead athletes, most commonly baseball pitchers, are at risk of developing UCL insufficiency, and dysfunction presents as pain with loss of velocity and control. Some injuries may present acutely while throwing, but many patients, when questioned, report a preceding period of either pain or loss of velocity and control.

Authors have documented a significant rise in elbow injuries in young athletes, especially pitchers.⁶ Extended seasons, higher pitch counts, year-round pitching, pitching while fatigued, and pitching for multiple teams are risk factors for elbow injuries.⁷ Pitchers in the southern United States are more likely to undergo UCL reconstruction than those from the northern states.⁸ Pitchers who also play catcher are at a higher risk due to more total throws than those who pitch and play other positions or pitch only. Throwers with higher velocity are more likely to pitch in showcases, pitch for multiple teams, and pitch with pain and fatigue, and these are all risk factors.⁶ Also, in one study of youth baseball injuries, individuals in the injured group were found to be taller and heavier than those in the uninjured group.⁶ Pitch counts, rest from pitching during the off-season, adequate rest, and ensuring pain-free pitching can lessen the risk of injury.⁶ As expected with the rise in throwing injuries, the rise in medial elbow procedures has risen.⁹

While throwing, stress across the medial elbow has been measured to be nearly 300 N. A maximum varus force during pitching was measured to be 64 N-m at 95° ± 14°.¹⁰ Morrey and An⁴ determined that the UCL generated 54% of the varus force at 90° of flexion. During active pitching, this value is likely reduced due to simultaneous muscle contraction, but if one assumes the UCL bears 54% of the maximal load, the UCL must be able to withstand 34 N-m. The UCL can withstand a maximum valgus torque between 22.7 and 34 N-m^11-13; therefore, during pitching, the UCL is at or above its failure load. After thousands of cycles over many years, one can imagine how the UCL might be injured.

Multiple techniques have been proposed in the surgical treatment of UCL injuries. Jobe¹⁴ pioneered UCL reconstruction in 1974 in Tommy John, a Major League Baseball pitcher. John returned to pitch successfully, and both the UCL and the reconstruction are commonly called by his name. Jobe¹⁴ reported his technique in 1986, and it has remained, with a few modifications, the primary method for reconstruction of the UCL (Figure 1).

Primary repair has been reported, and the best results have been in younger pitchers with acute injuries.¹⁵ Cain and colleagues¹⁶ reported a 70% return to same or higher level with repair alone, which was an improvement on Azar’s series¹⁷ with 63% return to same or higher level. Recent advancements have included primary repair with augmentation using grafts or anchored suture or tape¹⁸ (Figure 2).

The modified Jobe and docking techniques remain the most commonly used techniques with reproducible and reliable results.^19,20

Evaluation

A standard evaluation with physical examination and imaging is completed in all throwers with elbow pain. In our prior study,¹⁶ we found that 100% of patients experienced pain during athletic activity and that 96% of throwers complained of pain during late cocking and acceleration phases of the throwing motion. Nearly half reported an acute onset of pain, while 53% were unable to identify a single inciting event. Seventy-five percent of the acute injuries were during competition. Delayed diagnosis was very common, with an average time to diagnosis after onset of symptoms of 6.4 months. Neurologic symptoms were seen in 23% of athletes, most of which were ulnar nerve paresthesias during throwing.¹⁶

Physical examination includes inspection for swelling, hand intrinsic atrophy, neurovascular examination, range of motion, shoulder examination, and elbow stress examination. Range of motion at presentation averaged 5° to 135° with 85° of supination and pronation.¹⁶ All patients need neurologic evaluation for ulnar nerve dysfunction. Tinel test of the cubital tunnel was positive in 21%.¹⁶ Significant ulnar nerve dysfunction, including hand weakness, is much less common but must be well examined and documented. The shoulder must also be evaluated for loss of rotation, which can lead to increased stress on the elbow. An evaluation of mechanics may point out flaws in technique, which may be contributing to elbow stress. The UCL stress examination includes static stress at 30° of flexion, the milking test at 90°, and the moving valgus stress test. The presence of pain directly over the UCL or laxity compared to the uninvolved side is suggestive of UCL injury.

Radiographic evaluation is completed in all patients with concern for UCL injury. Standard x-rays of the elbow, including anteroposterior, medial, and lateral obliques, axial olecranon, and lateral views, are obtained to evaluate bony abnormalities. Fifty-seven percent of our series showed some abnormality, most commonly olecranon osteophyte formation or ectopic calcification within the UCL substance. Stress radiography rarely changed the treatment course and is somewhat difficult to interpret because of the reports documenting normal increased medial elbow opening in the dominant arm of throwing athletes.²¹ Magnetic resonance imaging (MRI) is obtained very commonly in this patient population, and intra-articular contrast is crucial. Partial, undersurface tears are common, and a contrasted study better demonstrates undersurface tears or avulsions. The T-sign as described by Timmerman and colleagues²² using computed tomography (CT) arthrography shows partial undersurface detachment, which can be difficult to see without intra-articular contrast.²² This finding is very well visualized on MRI arthrogram as well (Figure 3).

Sensitivity in partial tears is also highly favorable for CT arthrogram over noncontrasted MRI, detecting 71% vs 14%.²² MRI with arthrogram provides further detail to better detect tears and to determine the condition of the ligament, and is currently the gold standard diagnostic test for UCL evaluation.

 

Nonoperative Management

Nonoperative treatment is recommended for 3 months prior to performing reconstruction. Patients are given complete rest from throwing, but rehabilitation is initiated immediately. Rehabilitation exercises and nonsteroidal anti-inflammatory medications are prescribed, and activities that place valgus stress across the elbow are avoided. After resolution of symptoms, an interval throwing program is initiated, and the athlete is gradually returned to sport. Unfortunately, due to season-specific schedules and time-sensitive demands in high-level throwers, operative treatment is often chosen without an extended period of conservative treatment.

Platelet-rich plasma (PRP) therapy has recently been shown to improve healing rates and promote healing in partial UCL tears,²³ and as orthobiologics are advanced, they will likely play a larger role in the treatment of UCL injuries.

Surgical Technique

At our institution, UCL reconstruction is performed with the modified Jobe technique as described by Azar and colleagues.¹⁷ Arthroscopy prior to reconstruction was routinely performed at our institution until we recognized that arthroscopy rarely changed the preoperative plan.¹⁶ Currently, the presence of anterior pathology such as loose bodies or osteochondral defect is our only indication for arthroscopy before reconstruction.

Ipsilateral palmaris autograft is our current graft of choice. This must be examined preoperatively because 16% of patients have unilateral absence and 9% have bilateral absence.²⁴ In revision cases or in patients with insufficient or absent palmaris, contralateral palmaris followed by contralateral gracilis tendon is used. The contralateral gracilis is chosen because of ease of setup and position of the surgeon during the harvest. Gracilis tendon is also used in cases with bony involvement of the ligament based on the results from Dugas and colleagues.²⁵ Toe extensors, plantaris, and patellar tendon grafts have also been used. One recent study showed that neither graft choice nor diameter affected resistance to valgus stress, and that all reconstruction types restored strength at 60° to 120° of flexion.²⁶

Ulnar nerve transposition is performed in all cases regardless of the presence of preoperative nerve symptoms. A complete decompression is completed proximally to the Arcade of Struthers and distally to the deep portion of the flexor carpi ulnaris. A single fascial sling of medial intermuscular septum originating from the epicondylar attachment is used to stabilize the nerve without compression. At wound closure, the deep fascia on the posterior skin flap is also sewn into the cubital tunnel to prevent the nerve from subluxating back into the groove. A single suture is placed distally closing the muscle fascia to prevent propagation of the fascial incision, which can lead to herniation. Transposition is necessary because of the ulnar nerve exposure required in the modified Jobe technique to allow elevation of the deep flexor muscle mass for ligament exposure.

The reconstruction is completed as described by Jobe¹⁴ but with a few modifications as described by Azar and colleagues¹⁷ and slight adaptations implemented since that time. The flexor-pronator mass is retracted laterally instead of detachment or splitting as described by Thompson and colleagues.²⁷ A subcutaneous rather than a submuscular ulnar nerve transposition is used.

The patient is positioned supine using an arm board. If gracilis tendon is chosen, the contralateral leg is prepped and draped simultaneously. A tourniquet is inflated after exsanguination. A medial approach is performed, and the medial antebrachial nerve is located and protected. The ulnar nerve is then located in the cubital tunnel and mobilized. The neurolysis extends to the deep portion of the flexor carpi ulnaris distally and proximally to the Arcade of Struthers, and the nerve is retracted with a vessel loop. The flexor muscle mass is not elevated from the medial epicondyle; rather, it is retracted anteriorly by small Hohmann retractors. The dissection is carried down to the UCL and found at its attachments to the medial epicondyle and sublime tubercle. If no tear is seen on the superficial surface of the ligament, a longitudinal incision is made through the ligament. Undersurface tears, partial tears, and avulsions can then be identified (Figure 4).

Often, a portion of the ligament is degenerative and is excised, leaving only healthy-appearing ligament.

The autologous graft of choice is then harvested. Our technique for palmaris harvest is performed with three 1-cm transverse incisions. The palmaris is palpated and marked with the first incision made near the distal wrist crease, and the second incision is made 3 to 4 cm proximal to the first. The tendon is found in both distal incisions and cut distally with the wrist flexed to maximize tendon length. The tendon is then pulled through the second incision and tensioned to identify the most proximal location the tendon can be palpated. A third incision is made directly over this point and carried down to cut the tendon. This usually provides a graft length of 15 to 20 cm; 13 cm is the minimum graft length to ensure good graft fixation. Muscle is removed from the tendon and each end is secured with a No. 1 nonabsorbable suture in a locking fashion.

If posterior osteophytes are present, they are removed through a posterior, vertical arthrotomy. Over-resection of the olecranon must be avoided, as this can further destabilize the elbow and place increased stress on the reconstruction. Posterior loose bodies can also be removed through this arthrotomy. The arthrotomy is then closed with absorbable suture.

Tunnel placement is critical to success. A 3.2-mm drill bit is used with palmaris grafts and a 4-mm drill bit is used with gracilis grafts. Two convergent tunnels are drilled in the medial epicondyle in a Y fashion and 2 convergent tunnels are drilled at the sublime tubercle in a U or V fashion. After drilling the first tunnel on each side, a hemostat is placed in the tunnel as an aiming point to ensure a complete tunnel is made. The junction is smoothed with a curette, leaving a 5-mm bone bridge between the articular surface and the tunnels. A bent Hewson suture passer is used to pass one end of the graft through the ulna. The 2 limbs of the tendon graft are then passed through the humeral tunnels, creating a figure-of-eight. A varus stress is applied with the elbow at roughly 30° and the 2 limbs are tied together with a No. 1 nonabsorbable suture. If enough graft remains, one or both limbs are passed back through the tunnels and secured again with No. 1 nonabsorbable suture. The 2 limbs are then tied side-to-side, incorporating the native ligament to further secure and tighten the reconstruction.

The ulnar nerve is then secured using a strip of medial intermuscular septum left intact to its insertion at the medial epicondyle. This is attached to the flexor-pronator muscle fascia with a 3-0 nonabsorbable suture. Enough length should be harvested from the septum to ensure there is no compression on the nerve. The deep posterior fascial tissue is then sewn to the periosteum of the medial epicondyle to further prevent subluxation of the nerve back into the groove. The skin is then closed in layered fashion over a superficial drain. The patient is placed in a well-padded posterior splint for 1 week, then the rehabilitation protocol is initiated as discussed below.

 

Postoperative Rehabilitation

A standardized postoperative 4-phase rehabilitation program for ulnar collateral reconstruction is followed as described by Wilk and colleagues.^28-30 The first phase begins immediately after surgery and continues for 4 weeks. During surgery, the patient’s elbow is placed in a compression dressing with a posterior splint to immobilize the elbow in 90° of flexion with wrist motion for 1 week to allow initial healing. Full range of motion of the elbow joint is restored by the end of the fifth to sixth week after surgery.

During phase II (weeks 4-10), a progressive isotonic strengthening program is initiated. Exercises are focused on scapular, rotator cuff, deltoid, and arm musculature. Shoulder range of motion and stretching exercises are performed during this phase and the Thrower’s Ten exercise program is initiated. Any adaptations or strength deficits are addressed during this phase.

During the advanced strengthening phase (phase III), from weeks 10 to 16, a sport-specific exercise/rehabilitation program is initiated. During this phase, stretching and flexibility exercises are performed to enhance strength, power, and endurance. During this phase the patient is placed on the advanced Thrower’s Ten program. Isotonic strengthening exercises are progressed, and at week 12, the athlete is allowed to begin an isotonic lifting program, including bench press, seated rowing, latissimus dorsi pull downs, triceps push downs, and biceps curls. In addition, the athlete performs specific exercises to emphasize sport-specific movements. At week 12, overhead athletes begin a 2-hand plyometric throwing program, and at 14 weeks, a 1-hand plyometric throwing program. Furthermore, endurance exercises, core stability, and leg strengthening are emphasized during phase III. Phase IV, the return to activity phase (week 16 and beyond), is characterized by the initiation of an interval throwing program. The patient is instructed to continue his stretching and strengthening program. An interval throwing program off the mound is gradually initiated at 5 to 6 months postoperative and a gradual return to competition is initiated for pitchers at 9 months and for position players 6 to 7 months postoperative.

Discussion

Results after ulnar collateral reconstruction have been good. In our series of 743 patients, 83% returned to the same or higher level at an average of 11.6 months.¹⁶ There was a 4% major complication rate and 16% minor complication rate. Major complications included medial epicondyle fracture (0.5%), significant ulnar nerve dysfunction (1 patient), rupture of graft (1%), and graft site infection. Sixteen percent of patients had ulnar nerve dysfunction, and 82% of these resolved within 6 weeks. All but 1 patient’s paresthesias resolved within 1 year.¹⁶ The 10-year follow-up of this group of patients included 256 patients and was reported by Osbahr and colleagues³¹ in 2014. Retirement from baseball was due to reasons other than the elbow in 86%, and 98% were still able to throw on at least a recreational level. The overall longevity was 3.6 years, with 2.9 years at pre-injury level or higher. Statistically, pitchers performed at a higher level after reconstruction.³¹

A recent review by Erickson and colleagues⁹ showed an overall 82% excellent and 8% good result when evaluating different techniques, including the American Sports Medicine Institute (ASMI) modification of Jobe’s technique, docking technique, and Jobe’s technique. With an overall complication rate of 10% (75% of which was transient ulnar neuritis), the procedure was deemed overall a safe surgical option. Collegiate athletes had the highest return to sport (95%) compared with high school athletes (89%) and professional athletes (86%). The docking technique had the highest rate of return to play (97%) compared with ASMI technique (93%) and Jobe technique (66%).⁹ Results after repair have not been as good as reconstruction, as reported in 2 studies.^16,32 Savoie and colleagues,¹⁵ however, reported 93% good/excellent results after primary UCL repair alone.

Another recent review of outcomes showed an overall return to same or higher level was best with docking or modified docking techniques (90.4% and 91.3%, respectively).¹⁹ Overall return with modified Jobe technique was 77%.¹⁹ O’Brien and colleagues²⁰ performed a review of 33 patients with either modified Jobe or docking technique that showed 81% return to same or higher level with modified Jobe vs 92% with docking technique. The Kerlan-Jobe Orthopaedic Clinic scores were higher in the modified Jobe group (79 vs 74) and the docking technique group returned to play nearly 1 month sooner (12.4 months vs 11.8 months).²⁰ However, comparing different techniques in a heterogenous patient population over 40 years is difficult. Many of the modified Jobe technique cases were performed in the early evolution of the rehabilitation and return-to-play programs. We believe that the current modified Jobe technique has results equal to any other variation.

Despite good results with reconstructions, the recovery is lengthy and most pitchers cannot fully return to competition level for 12 to 18 months. Extensive research has been performed in exploring alternatives to the traditional reconstruction. Advancements in orthobiologics and development of new surgical options seem to provide an alternative to reconstruction, and may allow faster return to competition with less morbidity.

PRP has been at the forefront of orthopedic research for the last 2 decades, mostly focused in tendon and bone healing. Due to the release of many inflammatory mediators, PRP is theorized to initiate a healing response with growth factors that can direct healing towards normal tissue.³³ Two main types of PRP are reported based on the presence or absence of leukocytes. PRP has been studied in many applications, but only one clinical study on the UCL has been published to date. Podesta and colleagues²³ injected PRP into the elbow of 34 baseball players with MRI-confirmed partial UCL tear. The athletes then underwent a rehabilitation program, which limited stress across the UCL. Type 1A PRP was used (leukocyte-rich, unactivated, 5x or greater platelet concentration³³). Athletes were allowed to return to sport based on symptoms and examination findings. Eighty-eight percent returned to same level of play without complaints at average 70 week follow-up, and average return to play ranged from 10 to 15 weeks.²³ No specific data were given on the 16 pitchers in the group, but with such a high rate of return, PRP needs to be further evaluated in the treatment of UCL injuries.

Another recent study from Dugas and colleagues¹⁸ presented primary UCL repair using a tape augment (InternalBrace, Arthrex). Nine matched cadaver elbows underwent UCL sectioning and then either modified Jobe reconstruction or primary repair of the UCL with placement of the InternalBrace. The biomechanical data showed the repair with internal brace to have slightly less gap, more stiffness, and higher failure strength, although these findings were not statistically significant.¹⁸ This bone-preserving technique with less exposure and healing of the native ligament may be another step towards good results with a quicker return to throwing.

 

Conclusion

UCL injuries can be disabling in throwers. Reconstruction has afforded throwers a high rate of return to preinjury function or better, and several techniques have been presented that produce acceptable results. Overall complication rates range from 10% to 15%, and the majority of complications are transient ulnar neuropraxias. Orthobiologics and repair with augmentation have more recently offered additional options that may improve success of nonoperative treatment or allow less-invasive surgical treatment. Increased involvement in youth sports and early specialization is driving injury rates in young athletes. The orthopedic community must continue to look for better ways to prevent these injuries and investigate better methods to return athletes to high-level competition.

Am J Orthop. 2016;45(7):E534-E540. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The ulnar collateral ligament (UCL) is the primary restraint to valgus stress between 20° and 125° of motion.^1-5 Overhead athletes, most commonly baseball pitchers, are at risk of developing UCL insufficiency, and dysfunction presents as pain with loss of velocity and control. Some injuries may present acutely while throwing, but many patients, when questioned, report a preceding period of either pain or loss of velocity and control.

Authors have documented a significant rise in elbow injuries in young athletes, especially pitchers.⁶ Extended seasons, higher pitch counts, year-round pitching, pitching while fatigued, and pitching for multiple teams are risk factors for elbow injuries.⁷ Pitchers in the southern United States are more likely to undergo UCL reconstruction than those from the northern states.⁸ Pitchers who also play catcher are at a higher risk due to more total throws than those who pitch and play other positions or pitch only. Throwers with higher velocity are more likely to pitch in showcases, pitch for multiple teams, and pitch with pain and fatigue, and these are all risk factors.⁶ Also, in one study of youth baseball injuries, individuals in the injured group were found to be taller and heavier than those in the uninjured group.⁶ Pitch counts, rest from pitching during the off-season, adequate rest, and ensuring pain-free pitching can lessen the risk of injury.⁶ As expected with the rise in throwing injuries, the rise in medial elbow procedures has risen.⁹

While throwing, stress across the medial elbow has been measured to be nearly 300 N. A maximum varus force during pitching was measured to be 64 N-m at 95° ± 14°.¹⁰ Morrey and An⁴ determined that the UCL generated 54% of the varus force at 90° of flexion. During active pitching, this value is likely reduced due to simultaneous muscle contraction, but if one assumes the UCL bears 54% of the maximal load, the UCL must be able to withstand 34 N-m. The UCL can withstand a maximum valgus torque between 22.7 and 34 N-m^11-13; therefore, during pitching, the UCL is at or above its failure load. After thousands of cycles over many years, one can imagine how the UCL might be injured.

Multiple techniques have been proposed in the surgical treatment of UCL injuries. Jobe¹⁴ pioneered UCL reconstruction in 1974 in Tommy John, a Major League Baseball pitcher. John returned to pitch successfully, and both the UCL and the reconstruction are commonly called by his name. Jobe¹⁴ reported his technique in 1986, and it has remained, with a few modifications, the primary method for reconstruction of the UCL (Figure 1).

Primary repair has been reported, and the best results have been in younger pitchers with acute injuries.¹⁵ Cain and colleagues¹⁶ reported a 70% return to same or higher level with repair alone, which was an improvement on Azar’s series¹⁷ with 63% return to same or higher level. Recent advancements have included primary repair with augmentation using grafts or anchored suture or tape¹⁸ (Figure 2).

The modified Jobe and docking techniques remain the most commonly used techniques with reproducible and reliable results.^19,20

Evaluation

A standard evaluation with physical examination and imaging is completed in all throwers with elbow pain. In our prior study,¹⁶ we found that 100% of patients experienced pain during athletic activity and that 96% of throwers complained of pain during late cocking and acceleration phases of the throwing motion. Nearly half reported an acute onset of pain, while 53% were unable to identify a single inciting event. Seventy-five percent of the acute injuries were during competition. Delayed diagnosis was very common, with an average time to diagnosis after onset of symptoms of 6.4 months. Neurologic symptoms were seen in 23% of athletes, most of which were ulnar nerve paresthesias during throwing.¹⁶

Physical examination includes inspection for swelling, hand intrinsic atrophy, neurovascular examination, range of motion, shoulder examination, and elbow stress examination. Range of motion at presentation averaged 5° to 135° with 85° of supination and pronation.¹⁶ All patients need neurologic evaluation for ulnar nerve dysfunction. Tinel test of the cubital tunnel was positive in 21%.¹⁶ Significant ulnar nerve dysfunction, including hand weakness, is much less common but must be well examined and documented. The shoulder must also be evaluated for loss of rotation, which can lead to increased stress on the elbow. An evaluation of mechanics may point out flaws in technique, which may be contributing to elbow stress. The UCL stress examination includes static stress at 30° of flexion, the milking test at 90°, and the moving valgus stress test. The presence of pain directly over the UCL or laxity compared to the uninvolved side is suggestive of UCL injury.

Radiographic evaluation is completed in all patients with concern for UCL injury. Standard x-rays of the elbow, including anteroposterior, medial, and lateral obliques, axial olecranon, and lateral views, are obtained to evaluate bony abnormalities. Fifty-seven percent of our series showed some abnormality, most commonly olecranon osteophyte formation or ectopic calcification within the UCL substance. Stress radiography rarely changed the treatment course and is somewhat difficult to interpret because of the reports documenting normal increased medial elbow opening in the dominant arm of throwing athletes.²¹ Magnetic resonance imaging (MRI) is obtained very commonly in this patient population, and intra-articular contrast is crucial. Partial, undersurface tears are common, and a contrasted study better demonstrates undersurface tears or avulsions. The T-sign as described by Timmerman and colleagues²² using computed tomography (CT) arthrography shows partial undersurface detachment, which can be difficult to see without intra-articular contrast.²² This finding is very well visualized on MRI arthrogram as well (Figure 3).

Sensitivity in partial tears is also highly favorable for CT arthrogram over noncontrasted MRI, detecting 71% vs 14%.²² MRI with arthrogram provides further detail to better detect tears and to determine the condition of the ligament, and is currently the gold standard diagnostic test for UCL evaluation.

 

Nonoperative Management

Nonoperative treatment is recommended for 3 months prior to performing reconstruction. Patients are given complete rest from throwing, but rehabilitation is initiated immediately. Rehabilitation exercises and nonsteroidal anti-inflammatory medications are prescribed, and activities that place valgus stress across the elbow are avoided. After resolution of symptoms, an interval throwing program is initiated, and the athlete is gradually returned to sport. Unfortunately, due to season-specific schedules and time-sensitive demands in high-level throwers, operative treatment is often chosen without an extended period of conservative treatment.

Platelet-rich plasma (PRP) therapy has recently been shown to improve healing rates and promote healing in partial UCL tears,²³ and as orthobiologics are advanced, they will likely play a larger role in the treatment of UCL injuries.

Surgical Technique

At our institution, UCL reconstruction is performed with the modified Jobe technique as described by Azar and colleagues.¹⁷ Arthroscopy prior to reconstruction was routinely performed at our institution until we recognized that arthroscopy rarely changed the preoperative plan.¹⁶ Currently, the presence of anterior pathology such as loose bodies or osteochondral defect is our only indication for arthroscopy before reconstruction.

Ipsilateral palmaris autograft is our current graft of choice. This must be examined preoperatively because 16% of patients have unilateral absence and 9% have bilateral absence.²⁴ In revision cases or in patients with insufficient or absent palmaris, contralateral palmaris followed by contralateral gracilis tendon is used. The contralateral gracilis is chosen because of ease of setup and position of the surgeon during the harvest. Gracilis tendon is also used in cases with bony involvement of the ligament based on the results from Dugas and colleagues.²⁵ Toe extensors, plantaris, and patellar tendon grafts have also been used. One recent study showed that neither graft choice nor diameter affected resistance to valgus stress, and that all reconstruction types restored strength at 60° to 120° of flexion.²⁶

Ulnar nerve transposition is performed in all cases regardless of the presence of preoperative nerve symptoms. A complete decompression is completed proximally to the Arcade of Struthers and distally to the deep portion of the flexor carpi ulnaris. A single fascial sling of medial intermuscular septum originating from the epicondylar attachment is used to stabilize the nerve without compression. At wound closure, the deep fascia on the posterior skin flap is also sewn into the cubital tunnel to prevent the nerve from subluxating back into the groove. A single suture is placed distally closing the muscle fascia to prevent propagation of the fascial incision, which can lead to herniation. Transposition is necessary because of the ulnar nerve exposure required in the modified Jobe technique to allow elevation of the deep flexor muscle mass for ligament exposure.

The reconstruction is completed as described by Jobe¹⁴ but with a few modifications as described by Azar and colleagues¹⁷ and slight adaptations implemented since that time. The flexor-pronator mass is retracted laterally instead of detachment or splitting as described by Thompson and colleagues.²⁷ A subcutaneous rather than a submuscular ulnar nerve transposition is used.

The patient is positioned supine using an arm board. If gracilis tendon is chosen, the contralateral leg is prepped and draped simultaneously. A tourniquet is inflated after exsanguination. A medial approach is performed, and the medial antebrachial nerve is located and protected. The ulnar nerve is then located in the cubital tunnel and mobilized. The neurolysis extends to the deep portion of the flexor carpi ulnaris distally and proximally to the Arcade of Struthers, and the nerve is retracted with a vessel loop. The flexor muscle mass is not elevated from the medial epicondyle; rather, it is retracted anteriorly by small Hohmann retractors. The dissection is carried down to the UCL and found at its attachments to the medial epicondyle and sublime tubercle. If no tear is seen on the superficial surface of the ligament, a longitudinal incision is made through the ligament. Undersurface tears, partial tears, and avulsions can then be identified (Figure 4).

Often, a portion of the ligament is degenerative and is excised, leaving only healthy-appearing ligament.

The autologous graft of choice is then harvested. Our technique for palmaris harvest is performed with three 1-cm transverse incisions. The palmaris is palpated and marked with the first incision made near the distal wrist crease, and the second incision is made 3 to 4 cm proximal to the first. The tendon is found in both distal incisions and cut distally with the wrist flexed to maximize tendon length. The tendon is then pulled through the second incision and tensioned to identify the most proximal location the tendon can be palpated. A third incision is made directly over this point and carried down to cut the tendon. This usually provides a graft length of 15 to 20 cm; 13 cm is the minimum graft length to ensure good graft fixation. Muscle is removed from the tendon and each end is secured with a No. 1 nonabsorbable suture in a locking fashion.

If posterior osteophytes are present, they are removed through a posterior, vertical arthrotomy. Over-resection of the olecranon must be avoided, as this can further destabilize the elbow and place increased stress on the reconstruction. Posterior loose bodies can also be removed through this arthrotomy. The arthrotomy is then closed with absorbable suture.

Tunnel placement is critical to success. A 3.2-mm drill bit is used with palmaris grafts and a 4-mm drill bit is used with gracilis grafts. Two convergent tunnels are drilled in the medial epicondyle in a Y fashion and 2 convergent tunnels are drilled at the sublime tubercle in a U or V fashion. After drilling the first tunnel on each side, a hemostat is placed in the tunnel as an aiming point to ensure a complete tunnel is made. The junction is smoothed with a curette, leaving a 5-mm bone bridge between the articular surface and the tunnels. A bent Hewson suture passer is used to pass one end of the graft through the ulna. The 2 limbs of the tendon graft are then passed through the humeral tunnels, creating a figure-of-eight. A varus stress is applied with the elbow at roughly 30° and the 2 limbs are tied together with a No. 1 nonabsorbable suture. If enough graft remains, one or both limbs are passed back through the tunnels and secured again with No. 1 nonabsorbable suture. The 2 limbs are then tied side-to-side, incorporating the native ligament to further secure and tighten the reconstruction.

The ulnar nerve is then secured using a strip of medial intermuscular septum left intact to its insertion at the medial epicondyle. This is attached to the flexor-pronator muscle fascia with a 3-0 nonabsorbable suture. Enough length should be harvested from the septum to ensure there is no compression on the nerve. The deep posterior fascial tissue is then sewn to the periosteum of the medial epicondyle to further prevent subluxation of the nerve back into the groove. The skin is then closed in layered fashion over a superficial drain. The patient is placed in a well-padded posterior splint for 1 week, then the rehabilitation protocol is initiated as discussed below.

 

Postoperative Rehabilitation

A standardized postoperative 4-phase rehabilitation program for ulnar collateral reconstruction is followed as described by Wilk and colleagues.^28-30 The first phase begins immediately after surgery and continues for 4 weeks. During surgery, the patient’s elbow is placed in a compression dressing with a posterior splint to immobilize the elbow in 90° of flexion with wrist motion for 1 week to allow initial healing. Full range of motion of the elbow joint is restored by the end of the fifth to sixth week after surgery.

During phase II (weeks 4-10), a progressive isotonic strengthening program is initiated. Exercises are focused on scapular, rotator cuff, deltoid, and arm musculature. Shoulder range of motion and stretching exercises are performed during this phase and the Thrower’s Ten exercise program is initiated. Any adaptations or strength deficits are addressed during this phase.

During the advanced strengthening phase (phase III), from weeks 10 to 16, a sport-specific exercise/rehabilitation program is initiated. During this phase, stretching and flexibility exercises are performed to enhance strength, power, and endurance. During this phase the patient is placed on the advanced Thrower’s Ten program. Isotonic strengthening exercises are progressed, and at week 12, the athlete is allowed to begin an isotonic lifting program, including bench press, seated rowing, latissimus dorsi pull downs, triceps push downs, and biceps curls. In addition, the athlete performs specific exercises to emphasize sport-specific movements. At week 12, overhead athletes begin a 2-hand plyometric throwing program, and at 14 weeks, a 1-hand plyometric throwing program. Furthermore, endurance exercises, core stability, and leg strengthening are emphasized during phase III. Phase IV, the return to activity phase (week 16 and beyond), is characterized by the initiation of an interval throwing program. The patient is instructed to continue his stretching and strengthening program. An interval throwing program off the mound is gradually initiated at 5 to 6 months postoperative and a gradual return to competition is initiated for pitchers at 9 months and for position players 6 to 7 months postoperative.

Discussion

Results after ulnar collateral reconstruction have been good. In our series of 743 patients, 83% returned to the same or higher level at an average of 11.6 months.¹⁶ There was a 4% major complication rate and 16% minor complication rate. Major complications included medial epicondyle fracture (0.5%), significant ulnar nerve dysfunction (1 patient), rupture of graft (1%), and graft site infection. Sixteen percent of patients had ulnar nerve dysfunction, and 82% of these resolved within 6 weeks. All but 1 patient’s paresthesias resolved within 1 year.¹⁶ The 10-year follow-up of this group of patients included 256 patients and was reported by Osbahr and colleagues³¹ in 2014. Retirement from baseball was due to reasons other than the elbow in 86%, and 98% were still able to throw on at least a recreational level. The overall longevity was 3.6 years, with 2.9 years at pre-injury level or higher. Statistically, pitchers performed at a higher level after reconstruction.³¹

A recent review by Erickson and colleagues⁹ showed an overall 82% excellent and 8% good result when evaluating different techniques, including the American Sports Medicine Institute (ASMI) modification of Jobe’s technique, docking technique, and Jobe’s technique. With an overall complication rate of 10% (75% of which was transient ulnar neuritis), the procedure was deemed overall a safe surgical option. Collegiate athletes had the highest return to sport (95%) compared with high school athletes (89%) and professional athletes (86%). The docking technique had the highest rate of return to play (97%) compared with ASMI technique (93%) and Jobe technique (66%).⁹ Results after repair have not been as good as reconstruction, as reported in 2 studies.^16,32 Savoie and colleagues,¹⁵ however, reported 93% good/excellent results after primary UCL repair alone.

Another recent review of outcomes showed an overall return to same or higher level was best with docking or modified docking techniques (90.4% and 91.3%, respectively).¹⁹ Overall return with modified Jobe technique was 77%.¹⁹ O’Brien and colleagues²⁰ performed a review of 33 patients with either modified Jobe or docking technique that showed 81% return to same or higher level with modified Jobe vs 92% with docking technique. The Kerlan-Jobe Orthopaedic Clinic scores were higher in the modified Jobe group (79 vs 74) and the docking technique group returned to play nearly 1 month sooner (12.4 months vs 11.8 months).²⁰ However, comparing different techniques in a heterogenous patient population over 40 years is difficult. Many of the modified Jobe technique cases were performed in the early evolution of the rehabilitation and return-to-play programs. We believe that the current modified Jobe technique has results equal to any other variation.

Despite good results with reconstructions, the recovery is lengthy and most pitchers cannot fully return to competition level for 12 to 18 months. Extensive research has been performed in exploring alternatives to the traditional reconstruction. Advancements in orthobiologics and development of new surgical options seem to provide an alternative to reconstruction, and may allow faster return to competition with less morbidity.

PRP has been at the forefront of orthopedic research for the last 2 decades, mostly focused in tendon and bone healing. Due to the release of many inflammatory mediators, PRP is theorized to initiate a healing response with growth factors that can direct healing towards normal tissue.³³ Two main types of PRP are reported based on the presence or absence of leukocytes. PRP has been studied in many applications, but only one clinical study on the UCL has been published to date. Podesta and colleagues²³ injected PRP into the elbow of 34 baseball players with MRI-confirmed partial UCL tear. The athletes then underwent a rehabilitation program, which limited stress across the UCL. Type 1A PRP was used (leukocyte-rich, unactivated, 5x or greater platelet concentration³³). Athletes were allowed to return to sport based on symptoms and examination findings. Eighty-eight percent returned to same level of play without complaints at average 70 week follow-up, and average return to play ranged from 10 to 15 weeks.²³ No specific data were given on the 16 pitchers in the group, but with such a high rate of return, PRP needs to be further evaluated in the treatment of UCL injuries.

Another recent study from Dugas and colleagues¹⁸ presented primary UCL repair using a tape augment (InternalBrace, Arthrex). Nine matched cadaver elbows underwent UCL sectioning and then either modified Jobe reconstruction or primary repair of the UCL with placement of the InternalBrace. The biomechanical data showed the repair with internal brace to have slightly less gap, more stiffness, and higher failure strength, although these findings were not statistically significant.¹⁸ This bone-preserving technique with less exposure and healing of the native ligament may be another step towards good results with a quicker return to throwing.

 

Conclusion

UCL injuries can be disabling in throwers. Reconstruction has afforded throwers a high rate of return to preinjury function or better, and several techniques have been presented that produce acceptable results. Overall complication rates range from 10% to 15%, and the majority of complications are transient ulnar neuropraxias. Orthobiologics and repair with augmentation have more recently offered additional options that may improve success of nonoperative treatment or allow less-invasive surgical treatment. Increased involvement in youth sports and early specialization is driving injury rates in young athletes. The orthopedic community must continue to look for better ways to prevent these injuries and investigate better methods to return athletes to high-level competition.

Am J Orthop. 2016;45(7):E534-E540. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Approximately 600 cases of operating room (OR) fires are reported annually.¹ The incidence of OR fires in the United States equals that of wrong-site surgeries, and 20% of cases have associated morbidity.^1,2 The estimated mortality rate is 1 to 2 cases per year.^3-5 The most commonly involved anatomical regions are the airway (33%) and the face (28%).⁴ Most surgical fires are reported in anesthetized patients with open oxygen delivery systems during head, neck, and upper chest surgeries; electrosurgical instruments are the ignition source in 90% of these cases.⁶ Despite extensive fire safety education and training, complete elimination of OR fires still has not been achieved.

Each fire requires an ignition source, a fuel source, and an oxidizer.⁷ In the OR, the 2 most common oxidizers are oxygen and nitrous oxide. Head and neck surgeries have a high concentration of these gases near the working field and therefore a higher risk and incidence of fires. Furthermore, surgical drapes and equipment (eg, closed or semi-closed breathing systems, masks) may potentiate this risk by reducing ventilation in areas where gases can accumulate and ignite. Ignition sources provide the energy that starts fires; common sources are electrocautery, lasers, fiber-optic light cords, drills/burrs, and defibrillator paddles. Fires are propagated by fuel sources, which encompass any flammable material, including tracheal tubes, sponges, alcohol-based solutions, hair, gastrointestinal tract gases, gloves, and packaging materials.⁸ Of note, alcohol-based skin-preparation agents emit flammable vapors that can ignite.^9-14 Before draping or exposure to an ignition source, chlorhexidine gluconate-based preparations must be allowed to dry for at least 3 minutes after application to hairless skin and up to 1 hour after application to hair.¹⁵ Inadequate drying poses a risk of fire.¹⁰We present the case of an OR fire ignited by electrocautery near freshly applied bone cement. No patient information is disclosed in this report.

Case Report

Our patient was evaluated in clinic and scheduled for total knee arthroplasty (TKA). All preoperative safety checklists and time-out procedures were followed and documented at the start of surgery. The TKA was performed with a standard medial patellar arthrotomy. Tourniquet control was used after Esmarch exsanguination. The surgery proceeded uneventfully until just after the bone cement was applied to the tibial surface. The surgeon was using a Bovie to resect residual lateral meniscus tissue when a fire instantaneously erupted within the joint space. Fortunately, the surgeon quickly suffocated the fire with a dry towel. The ignited bone cement was removed, and the patient was examined. There was no injury to surrounding tissue or joint space. Surgery was resumed with application of new bone cement to the tibial surface. The artificial joint was then successfully implanted and the case completed without further incident. The patient was discharged from the hospital and followed up as an outpatient without any postoperative complications.

Discussion

Bone cement, which is commonly used in artificial joint anchoring, craniofacial reconstruction, and vertebroplasty, has liquid and powder components. The liquid monomer methyl methacrylate (MMA) is colorless and flammable and has a distinct odor.¹⁶ Exposure to heat or light can prematurely polymerize MMA, requiring the addition of hydroquinone to inhibit the reaction.¹⁶ The powder polymethylmethacrylate affords excellent structural support, radiopacity, and facility of use.¹⁷ Dibenzoyl peroxide and N,N-dimethyl-p-toluidine are added to the powder to facilitate the polymerization reaction at room temperature (ie, cold curing of cement). Premature application of unpolymerized cement increases the risk of fire from the volatile liquid component.

In the OR, bone cement is prepared by mixing together its powder and liquid components.¹⁸ The reaction is exothermic polymerization. The liquid is highly volatile and flammable in both liquid and vapor states.^16,19 The vapors are denser than air and can concentrate in poorly ventilated areas. The OR and the application site must be adequately ventilated to eliminate any pockets of vapor accumulation.¹⁶ A vacuum mixer can be used to minimize fume exposure, enhance cement strength, and reduce fire risk while combining the 2 components.

MMA’s flash point, the temperature at which the fumes could ignite in the presence of an ignition source, is 10.5ºC. The auto-ignition point, the temperature at which MMA spontaneously combusts, is 421ºC.²⁰ The OR is usually warmer than the flash point temperature, but the electrocautery tip can generate up to 1200ºC of heat.²¹ Therefore, bone cement is a potential fire hazard, and use of Bovies or other ignition sources in its vicinity must be avoided.

The Table lists the recommended times for preparing various bone cement products.^22,23Mix time is the time needed to combine the liquid and powder into a homogenous putty.

Pickup time is the minimum time required for putty to increase in viscosity, and no longer adhere to fingers. Work time is the time needed for the cement to be applied to the target anatomy and for subsequent implantation. Final set time is the time needed for final solidification and shaping of the applied cement. The risk of vapor ignition by a Bovie is highest during pickup time.¹⁶The flammability of bone cement mandates that, before surgery, the OR staff familiarize themselves with the work times of the cement they intend to use. In addition, the viscosity of the cement should be tested (with a powder-free latex gloved finger) before application.²³In the present case, resection of excess lateral meniscus tissue was attempted after the cement was applied. We recommend removing all residual tissue before applying wet cement. Blunt dissection may substitute for cautery when needed. Freer elevators and cement remover curettes may also be safely used. Use of an inactive Bovie for dissection should be avoided to prevent accidental activation and ignition. The risk of fire with bone cement decreases with appropriate use and with the OR staff’s increased experience.

For OR fires, the standard guidelines for rapid containment and safety apply. These guidelines are detailed by the American Society of Anesthesiologists.⁸ Briefly, delivery of all airway gases to the patient is discontinued. Any burning material is removed and extinguished by the OR staff.¹ Carbon dioxide fire extinguishers are used to put out any patient fires and minimize the risk of thermal injury. (Water-mist fire extinguishers can contaminate surgical wounds and present an electric shock hazard with surgical devices and should be avoided.²⁴) If a fire occurs in a patient’s airway, the tracheal tube is removed, and airway patency is maintained with use of other invasive or noninvasive techniques. Often, noninvasive positive pressure ventilation without supplemental oxygen is used until the fire is controlled and the patient is safe. Once the patient fire is controlled, ventilation is restarted, and the patient is evacuated from the OR and away from any other hazards, as required. Last, the patient is physically examined for any injuries and treated.²⁴ Specific to TKA, the procedure is resumed after removal of all bone cement, inspection of the operative site, and treatment of any fire-related injuries.

We have reported the case of an OR fire during TKA. Appropriate selection and use of bone cement products, proper assessment of set time, and avoidance of electrocautery near cement application sites may dramatically reduce associated fire risks.

Am J Orthop. 2016;45(7):E512-E514. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Approximately 600 cases of operating room (OR) fires are reported annually.¹ The incidence of OR fires in the United States equals that of wrong-site surgeries, and 20% of cases have associated morbidity.^1,2 The estimated mortality rate is 1 to 2 cases per year.^3-5 The most commonly involved anatomical regions are the airway (33%) and the face (28%).⁴ Most surgical fires are reported in anesthetized patients with open oxygen delivery systems during head, neck, and upper chest surgeries; electrosurgical instruments are the ignition source in 90% of these cases.⁶ Despite extensive fire safety education and training, complete elimination of OR fires still has not been achieved.

Each fire requires an ignition source, a fuel source, and an oxidizer.⁷ In the OR, the 2 most common oxidizers are oxygen and nitrous oxide. Head and neck surgeries have a high concentration of these gases near the working field and therefore a higher risk and incidence of fires. Furthermore, surgical drapes and equipment (eg, closed or semi-closed breathing systems, masks) may potentiate this risk by reducing ventilation in areas where gases can accumulate and ignite. Ignition sources provide the energy that starts fires; common sources are electrocautery, lasers, fiber-optic light cords, drills/burrs, and defibrillator paddles. Fires are propagated by fuel sources, which encompass any flammable material, including tracheal tubes, sponges, alcohol-based solutions, hair, gastrointestinal tract gases, gloves, and packaging materials.⁸ Of note, alcohol-based skin-preparation agents emit flammable vapors that can ignite.^9-14 Before draping or exposure to an ignition source, chlorhexidine gluconate-based preparations must be allowed to dry for at least 3 minutes after application to hairless skin and up to 1 hour after application to hair.¹⁵ Inadequate drying poses a risk of fire.¹⁰We present the case of an OR fire ignited by electrocautery near freshly applied bone cement. No patient information is disclosed in this report.

Case Report

Our patient was evaluated in clinic and scheduled for total knee arthroplasty (TKA). All preoperative safety checklists and time-out procedures were followed and documented at the start of surgery. The TKA was performed with a standard medial patellar arthrotomy. Tourniquet control was used after Esmarch exsanguination. The surgery proceeded uneventfully until just after the bone cement was applied to the tibial surface. The surgeon was using a Bovie to resect residual lateral meniscus tissue when a fire instantaneously erupted within the joint space. Fortunately, the surgeon quickly suffocated the fire with a dry towel. The ignited bone cement was removed, and the patient was examined. There was no injury to surrounding tissue or joint space. Surgery was resumed with application of new bone cement to the tibial surface. The artificial joint was then successfully implanted and the case completed without further incident. The patient was discharged from the hospital and followed up as an outpatient without any postoperative complications.

Discussion

Bone cement, which is commonly used in artificial joint anchoring, craniofacial reconstruction, and vertebroplasty, has liquid and powder components. The liquid monomer methyl methacrylate (MMA) is colorless and flammable and has a distinct odor.¹⁶ Exposure to heat or light can prematurely polymerize MMA, requiring the addition of hydroquinone to inhibit the reaction.¹⁶ The powder polymethylmethacrylate affords excellent structural support, radiopacity, and facility of use.¹⁷ Dibenzoyl peroxide and N,N-dimethyl-p-toluidine are added to the powder to facilitate the polymerization reaction at room temperature (ie, cold curing of cement). Premature application of unpolymerized cement increases the risk of fire from the volatile liquid component.

In the OR, bone cement is prepared by mixing together its powder and liquid components.¹⁸ The reaction is exothermic polymerization. The liquid is highly volatile and flammable in both liquid and vapor states.^16,19 The vapors are denser than air and can concentrate in poorly ventilated areas. The OR and the application site must be adequately ventilated to eliminate any pockets of vapor accumulation.¹⁶ A vacuum mixer can be used to minimize fume exposure, enhance cement strength, and reduce fire risk while combining the 2 components.

MMA’s flash point, the temperature at which the fumes could ignite in the presence of an ignition source, is 10.5ºC. The auto-ignition point, the temperature at which MMA spontaneously combusts, is 421ºC.²⁰ The OR is usually warmer than the flash point temperature, but the electrocautery tip can generate up to 1200ºC of heat.²¹ Therefore, bone cement is a potential fire hazard, and use of Bovies or other ignition sources in its vicinity must be avoided.

The Table lists the recommended times for preparing various bone cement products.^22,23Mix time is the time needed to combine the liquid and powder into a homogenous putty.

Pickup time is the minimum time required for putty to increase in viscosity, and no longer adhere to fingers. Work time is the time needed for the cement to be applied to the target anatomy and for subsequent implantation. Final set time is the time needed for final solidification and shaping of the applied cement. The risk of vapor ignition by a Bovie is highest during pickup time.¹⁶The flammability of bone cement mandates that, before surgery, the OR staff familiarize themselves with the work times of the cement they intend to use. In addition, the viscosity of the cement should be tested (with a powder-free latex gloved finger) before application.²³In the present case, resection of excess lateral meniscus tissue was attempted after the cement was applied. We recommend removing all residual tissue before applying wet cement. Blunt dissection may substitute for cautery when needed. Freer elevators and cement remover curettes may also be safely used. Use of an inactive Bovie for dissection should be avoided to prevent accidental activation and ignition. The risk of fire with bone cement decreases with appropriate use and with the OR staff’s increased experience.

For OR fires, the standard guidelines for rapid containment and safety apply. These guidelines are detailed by the American Society of Anesthesiologists.⁸ Briefly, delivery of all airway gases to the patient is discontinued. Any burning material is removed and extinguished by the OR staff.¹ Carbon dioxide fire extinguishers are used to put out any patient fires and minimize the risk of thermal injury. (Water-mist fire extinguishers can contaminate surgical wounds and present an electric shock hazard with surgical devices and should be avoided.²⁴) If a fire occurs in a patient’s airway, the tracheal tube is removed, and airway patency is maintained with use of other invasive or noninvasive techniques. Often, noninvasive positive pressure ventilation without supplemental oxygen is used until the fire is controlled and the patient is safe. Once the patient fire is controlled, ventilation is restarted, and the patient is evacuated from the OR and away from any other hazards, as required. Last, the patient is physically examined for any injuries and treated.²⁴ Specific to TKA, the procedure is resumed after removal of all bone cement, inspection of the operative site, and treatment of any fire-related injuries.

We have reported the case of an OR fire during TKA. Appropriate selection and use of bone cement products, proper assessment of set time, and avoidance of electrocautery near cement application sites may dramatically reduce associated fire risks.

Am J Orthop. 2016;45(7):E512-E514. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Approximately 600 cases of operating room (OR) fires are reported annually.¹ The incidence of OR fires in the United States equals that of wrong-site surgeries, and 20% of cases have associated morbidity.^1,2 The estimated mortality rate is 1 to 2 cases per year.^3-5 The most commonly involved anatomical regions are the airway (33%) and the face (28%).⁴ Most surgical fires are reported in anesthetized patients with open oxygen delivery systems during head, neck, and upper chest surgeries; electrosurgical instruments are the ignition source in 90% of these cases.⁶ Despite extensive fire safety education and training, complete elimination of OR fires still has not been achieved.

Each fire requires an ignition source, a fuel source, and an oxidizer.⁷ In the OR, the 2 most common oxidizers are oxygen and nitrous oxide. Head and neck surgeries have a high concentration of these gases near the working field and therefore a higher risk and incidence of fires. Furthermore, surgical drapes and equipment (eg, closed or semi-closed breathing systems, masks) may potentiate this risk by reducing ventilation in areas where gases can accumulate and ignite. Ignition sources provide the energy that starts fires; common sources are electrocautery, lasers, fiber-optic light cords, drills/burrs, and defibrillator paddles. Fires are propagated by fuel sources, which encompass any flammable material, including tracheal tubes, sponges, alcohol-based solutions, hair, gastrointestinal tract gases, gloves, and packaging materials.⁸ Of note, alcohol-based skin-preparation agents emit flammable vapors that can ignite.^9-14 Before draping or exposure to an ignition source, chlorhexidine gluconate-based preparations must be allowed to dry for at least 3 minutes after application to hairless skin and up to 1 hour after application to hair.¹⁵ Inadequate drying poses a risk of fire.¹⁰We present the case of an OR fire ignited by electrocautery near freshly applied bone cement. No patient information is disclosed in this report.

Case Report

Our patient was evaluated in clinic and scheduled for total knee arthroplasty (TKA). All preoperative safety checklists and time-out procedures were followed and documented at the start of surgery. The TKA was performed with a standard medial patellar arthrotomy. Tourniquet control was used after Esmarch exsanguination. The surgery proceeded uneventfully until just after the bone cement was applied to the tibial surface. The surgeon was using a Bovie to resect residual lateral meniscus tissue when a fire instantaneously erupted within the joint space. Fortunately, the surgeon quickly suffocated the fire with a dry towel. The ignited bone cement was removed, and the patient was examined. There was no injury to surrounding tissue or joint space. Surgery was resumed with application of new bone cement to the tibial surface. The artificial joint was then successfully implanted and the case completed without further incident. The patient was discharged from the hospital and followed up as an outpatient without any postoperative complications.

Discussion

Bone cement, which is commonly used in artificial joint anchoring, craniofacial reconstruction, and vertebroplasty, has liquid and powder components. The liquid monomer methyl methacrylate (MMA) is colorless and flammable and has a distinct odor.¹⁶ Exposure to heat or light can prematurely polymerize MMA, requiring the addition of hydroquinone to inhibit the reaction.¹⁶ The powder polymethylmethacrylate affords excellent structural support, radiopacity, and facility of use.¹⁷ Dibenzoyl peroxide and N,N-dimethyl-p-toluidine are added to the powder to facilitate the polymerization reaction at room temperature (ie, cold curing of cement). Premature application of unpolymerized cement increases the risk of fire from the volatile liquid component.

In the OR, bone cement is prepared by mixing together its powder and liquid components.¹⁸ The reaction is exothermic polymerization. The liquid is highly volatile and flammable in both liquid and vapor states.^16,19 The vapors are denser than air and can concentrate in poorly ventilated areas. The OR and the application site must be adequately ventilated to eliminate any pockets of vapor accumulation.¹⁶ A vacuum mixer can be used to minimize fume exposure, enhance cement strength, and reduce fire risk while combining the 2 components.

MMA’s flash point, the temperature at which the fumes could ignite in the presence of an ignition source, is 10.5ºC. The auto-ignition point, the temperature at which MMA spontaneously combusts, is 421ºC.²⁰ The OR is usually warmer than the flash point temperature, but the electrocautery tip can generate up to 1200ºC of heat.²¹ Therefore, bone cement is a potential fire hazard, and use of Bovies or other ignition sources in its vicinity must be avoided.

The Table lists the recommended times for preparing various bone cement products.^22,23Mix time is the time needed to combine the liquid and powder into a homogenous putty.

Pickup time is the minimum time required for putty to increase in viscosity, and no longer adhere to fingers. Work time is the time needed for the cement to be applied to the target anatomy and for subsequent implantation. Final set time is the time needed for final solidification and shaping of the applied cement. The risk of vapor ignition by a Bovie is highest during pickup time.¹⁶The flammability of bone cement mandates that, before surgery, the OR staff familiarize themselves with the work times of the cement they intend to use. In addition, the viscosity of the cement should be tested (with a powder-free latex gloved finger) before application.²³In the present case, resection of excess lateral meniscus tissue was attempted after the cement was applied. We recommend removing all residual tissue before applying wet cement. Blunt dissection may substitute for cautery when needed. Freer elevators and cement remover curettes may also be safely used. Use of an inactive Bovie for dissection should be avoided to prevent accidental activation and ignition. The risk of fire with bone cement decreases with appropriate use and with the OR staff’s increased experience.

For OR fires, the standard guidelines for rapid containment and safety apply. These guidelines are detailed by the American Society of Anesthesiologists.⁸ Briefly, delivery of all airway gases to the patient is discontinued. Any burning material is removed and extinguished by the OR staff.¹ Carbon dioxide fire extinguishers are used to put out any patient fires and minimize the risk of thermal injury. (Water-mist fire extinguishers can contaminate surgical wounds and present an electric shock hazard with surgical devices and should be avoided.²⁴) If a fire occurs in a patient’s airway, the tracheal tube is removed, and airway patency is maintained with use of other invasive or noninvasive techniques. Often, noninvasive positive pressure ventilation without supplemental oxygen is used until the fire is controlled and the patient is safe. Once the patient fire is controlled, ventilation is restarted, and the patient is evacuated from the OR and away from any other hazards, as required. Last, the patient is physically examined for any injuries and treated.²⁴ Specific to TKA, the procedure is resumed after removal of all bone cement, inspection of the operative site, and treatment of any fire-related injuries.

We have reported the case of an OR fire during TKA. Appropriate selection and use of bone cement products, proper assessment of set time, and avoidance of electrocautery near cement application sites may dramatically reduce associated fire risks.

Am J Orthop. 2016;45(7):E512-E514. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Healing after rotator cuff repair (RCR) can be challenging, especially in cases of large and massive tears, revision repairs, and tendons with poor tissue quality.^1-3 Poor tissue quality is associated with increased risk for recurrent tears, independent of age and tear size.³ Various techniques have been used to improve tendon fixation strength in these difficult situations, including augmented suture configurations (eg, massive cuff stitches, rip-stop stitches) and tissue grafts (eg, acellular dermal matrix).^4-9 Clinical studies have found improved healing rates for larger tears and revision repairs using acellular dermal matrix grafts.^6,10 Synthetic patches are another option for RCR augmentation, but limited clinical data and biomechanical evidence support use of synthetic grafts as an augment for RCRs.^11-13

Polyhydroxyalkanoates (PHAs) are a class of biodegradable polymers that have been used as orthopedic devices, tissue scaffolds, patches, and other applications with increasing frequency over the past decade.¹⁴ In the laboratory, these implanted materials have been shown to support cell migration and growth.¹⁵ The PHA family of polymers typically degrades by hydrolytic and bacterial depolymerase mechanisms over 52-plus weeks in vivo.¹⁴PHA grafts have been studied in the setting of RCR. An expanded polytetrafluoroethylene scaffold was shown to improve repair mechanics when used as a bursal side graft in an in vitro ovine model.¹¹ The graft increased tendon footprint contact pressure and failure loads by almost 180 N. In clinical studies, poly-L-lactic acid augmentations have been used to reinforce massive RCRs. Lenart and colleagues¹⁶ found that 38% of 16 patients with such tears had an intact rotator cuff at 1.2-year follow-up, and improvement in clinical scores. Proctor¹³ reported on use of a poly-L-lactic acid retrograde patch for reinforcement of massive tears with both single- and double-row repairs in 18 patients. The cohort had more favorable rates of intact cuffs at 12 months (83%) and 42 months (78%), and ASES (American Shoulder and Elbow Surgeons) scores improved from 25 before surgery to 82 at latest follow-up after surgery.

RCR augmentation traditionally has been performed with an open or mini-open technique.⁶ Recently, several authors have reported on arthroscopic techniques for augmentation with either acellular dermal matrix or synthetic grafts.^13,17,18 Most techniques have involved “bridging” with a graft or patch used to stress-shield a single-row repair.^8,9,13 This bridging typically involves placing several sutures medial to where the anchor repair stitches pass through the tendon. An alternative is to pass the repair stitches through both the tendon and the graft.^17-19 The overall volume of tissue incorporated into the repair stitches (rotator cuff plus graft) is increased with the augmented technique relative to the bridging technique. Both can be technically challenging, but the augmented technique may be easier to perform arthroscopically.^9,19 Regardless, these techniques are complicated and require a higher level of arthroscopic skills compared with those required in arthroscopic RCR without a graft. Simplifying arthroscopic graft augmentation likely will increase its utility because, even for skilled surgeons, adding a graft can increase operative time by 20 to 30 minutes. Simplification will also extend use of the technique to surgeons with less experience and proficiency with arthroscopic repair.

We developed a simple method for augmenting single-row RCR with a strip of bioresorbable soft-tissue scaffold. We also conducted a study to evaluate the initial biomechanical properties of single-row RCR in cadaveric shoulder specimens augmented with PHA mesh (BioFiber; Tornier) graft as compared with single-row RCR without augmentation. Both cyclic gap formation and ultimate failure loads and displacement were quantified. We hypothesized that the augmented RCRs would have decreased gap formation and increased ultimate failure loads compared with nonaugmented RCRs. This study was exempt from having to obtain Institutional Review Board approval.

Methods

Eight pairs of fresh-frozen cadaver humeri (6 male, 2 female; mean [SD] age, 61 [9] years) were dissected of all soft tissue (except rotator cuff) by Dr. Tashjian, a board-certified, fellowship-trained orthopedic surgeon. There were no qualitative differences in tendon condition between tendons within a pair. The supraspinatus muscle and tendon were separated from the other rotator cuff muscles. The infraspinatus, subscapularis, and teres minor were removed from the humerus. Last, the supraspinatus was resected at its insertion. Humeral pairs were then randomized into augmented and nonaugmented RCRs within each pair.

In the nonaugmented group, the supraspinatus was reattached to its insertion in a single-row RCR with 2 triple-loaded suture anchors (5.5-mm Insite FT Ti, No. 2 Force Fiber suture; Tornier) and 6 simple stitches (Figure 1A). Anchors were placed midway between the articular margin and the lateral edge of the greater tuberosity at about 45° to the bone surface.

Anchors were separated by 15 mm, with the anterior anchor 5 mm posterior to the biceps groove. Stitches were passed through the supraspinatus tendon, taking a 15-mm bite of tissue, with each stitch separated by 5 mm. Each suture was then tied with a Revo knot.

In the contralateral shoulders, augmented RCRs were performed. Specimens were prepared exactly as they were for the nonaugmented RCRs, including anchor placement and suture passage. Before knot tying, RCRs were augmented with 2 strips of 13-mm × 23-mm PHA mesh (BioFiber) (Figure 1B). One strip was used to augment the 3 sutures of each anchor, overlying the residual tendon, to reinforce the tendon–knot interface. After each suture was passed through the supraspinatus tendon from the intra-articular surface, the stitch was passed through the strip of PHA mesh. Stitches were separated by 5 mm in each mesh strip. All 6 sutures were then tied with a Revo knot between the free end of each suture leg and the leg that passed through the tendon and mesh.

Each humerus was transected at the midshaft and potted and mounted in an Instron 1331 load frame with Model 8800 controller (Instron). A cryoclamp was used to grasp the supraspinatus muscle belly above the musculotendinous junction (Figure 2).

The humerus was aligned in the mounting fixture such that loading was performed at a 135° angle with the humeral shaft (Figure 2).²⁰ The Instron, which was equipped with a 1-kN load cell (Dynacell Model 2527-130; Instron) to monitor applied force, measured applied displacement.

Three rows of 2-mm fiducial markers were affixed to the bone, tendon, and muscle belly with cyanoacrylate for tracking with a digital video system (DMAS Version 6.5; Spicatek) (Figure 3).21

Camera resolution was 1360 pixels × 1024 pixels, and DMAS accuracy for marker centroid tracking was rated at ± 0.005 mm. Construct gapping was defined as the difference in displacement between the markers at the tissue–suture interface and the markers on the bone. Tissue deformation was then defined as the displacement between the markers at the tissue–suture interface and the markers on the muscle belly. Mean gapping was defined from anterior to posterior across the construct using 3 sets of fiducial markers.

A 0.1-MPa pre-stress (applied force/tendon cross-sectional area) was applied to each construct to determine the starting position for the deformation profile. Each repair underwent 1000 cycles of uniaxial load-controlled displacement between 0.1 and 1.0 MPa of effective stress at 1 Hz. Effective stress was determined as the ratio of applied force to cross-sectional area of the tendon at harvest to normalize the applied loads between tendons of varying size. During cyclic testing, gapping of more than 5 mm was defined as construct failure.²² After cyclic loading, each construct was loaded to failure at 1.0 mm/s. Ultimate failure load was defined as the highest load achieved at the maximum displacement before rapid decline in load supported by the construct.

 

Statistical Analysis

Paired t tests were used to compare the matched pairs of constructs. For all tests, significance was set at P ≤ .05. Post hoc power was calculated for significant results using G*Power Version 3.1.6.²³ All data are presented as means (SDs).

Results

After 1000 cycles of displacement, mean (SD) gapping was 3.8 (0.9) mm for the nonaugmented repairs and 3.9 (1.1) mm for the PHA mesh–augmented repairs (P = .879) (Figure 4).

Mean (SD) tissue elongation above the construct was comparable (P = .276) between nonaugmented repairs, 0.5 (0.4) mm, and augmented repairs, 0.7 (0.4) mm. No specimens failed during cyclic load, as mean gapping was <4 mm²² in all constructs. Mean (SD) applied force was 11.8 (1.8) N at 0.1 MPa of effective stress and 117.8 (18.1) N at 1.0 MPa of effective stress. Applied force did not vary between constructs (P = .727).

For the nonaugmented repairs, mean (SD) failure displacement was 6.3 (1.7) mm, and mean (SD) ultimate failure load was 472.1 (120.3) N. For the PHA-augmented repairs, failure displacement was 5.5 (1.9) mm, and ultimate failure load was 571.2 (173.0) N. There was no difference in failure displacement (P = .393), but there was a difference in ultimate failure load (P = .042; power = 0.57). During failure testing, mean (SD) tissue deformation was higher (P = .012; power = 0.83) for the PHA-augmented repairs, 1.2 (0.7) mm, than for the nonaugmented repairs, 0.8 (0.5) mm. Failures, which were consistent within pairs, were caused by tissue failure, with sutures pulling through the tissue (4 pairs) or single anchor pullout before ultimate tissue failure (4 pairs). Of the 4 failures with anchor pullout, 3 had anterior anchor pullout, and 1 had posterior anchor pullout. In all specimens with anchor pullout, the second anchor remained stable, and ultimate failure occurred with tissue tearing at the suture interface. There were no significant differences in any metrics between specimens that failed with intact anchors and specimens with single anchor pullout (P ≥ .122). Therefore, both groups were pooled for the failure analysis.

Discussion

RCR augmentation with a synthetic graft is a viable option for improving fixation strength of supraspinatus repairs, as shown in otherwise healthy tendon in the present study. Our hypothesis that there would be decreased gap formation with graft augmentation was not supported, whereas the hypothesis of increased failure loads with graft augmentation was supported. These findings may also be applicable in cases of large tears, revisions, and tendons with poor tissue quality. Simplification of graft application techniques will allow quick and easy arthroscopic augmentation.

Studies of RCRs for large or massive tears have reported retear rates of 25% to 79%.^24-26 Latissimus dorsi tendon transfers also show promise in posterosuperior RCRs, with failure rates near 10%.^27,28 Although use of PHA patches in RCR augmentation is relatively new, short-term and midterm failure rates are in the range of 20% to 60% in the few small cohorts currently being studied.^13,16 It is possible that these rates may improve as indications, surgical experience, and techniques for use of PHA patches are further refined. Regardless, with PHA currently being used in practice, it is important to quantify the biomechanics of the augmentation as a baseline for its performance in reinforcing the tendon–suture interface.

We determined that the initial fixation strength of single-row repairs was higher with the addition of PHA synthetic grafts using a very simple technique. Single-row triple-loaded anchor repairs already provide high initial mechanical strength, and our results are similar to those of another study of this technique.²⁹ Despite the already high mechanical strength of a triple-loaded anchor repair, PHA mesh increased ultimate strength by about 100 N (~25%). Of note, tissue elongation during failure was higher (P = .012; power = 0.83) in the PHA-augmented group (1.2 mm) than in the nonaugmented group (0.8 mm). This was not surprising—failure loads were almost 100 N higher in the PHA-augmented group than in the nonaugmented group. Consequently, much higher forces were placed on the muscle belly, likely resulting in additional elongation of the intact tissue medial to the repair construct.

The ultimate failure loads in our study compare favorably with the biomechanical strength of augmented repairs reported by others.^8,9,18 Barber and colleagues¹⁸ evaluated an augmented single-row repair with 2 double-loaded suture anchors and an acellular dermal matrix graft. The ultimate failure load of the augmented repairs was 325 N. In contrast, Omae and colleagues⁸ tested a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft. Ultimate failure load of the augmented repairs was 560 N, similar to our finding. Last, Shea and colleagues⁹ evaluated a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft, with ultimate failure load of 429 N. The techniques in all 3 studies can be performed arthroscopically but are challenging and require multiple extra sutures and anchors that need management and tying. Our technique provides similar initial fixation strength, has no requirement for extra sutures or anchors, and is very simple to perform.

The supraspinatus tendon is estimated to fail between 800 N and 1000 N.^30,31 Biomechanical shoulder simulators use supraspinatus forces in the range of 20 N to 200 N for scapular plane abduction.^32-36 Therefore, the single-row repair failures in our study fell between functional and full-thickness failure loads. Studies on the mechanics of degenerated human supraspinatus tendon are limited, but there is evidence the mechanical properties of these tissues are inferior to those of healthy tendon.³⁷ A 100-N increase in failure loads with PHA augmentation may prove highly significant in reinforcing the suture–tendon interface in degenerated tendons.

Adding the mesh did not have any effect on gapping at the repair site after cyclic loading. This finding suggests that construct gapping under cyclic loading is not a function of a reinforced knot–tendon interface but is instead caused by microtearing and cinching of the suture constructs in relation to the underlying bone. Tissue elongation likely was not a strong contributor to overall cyclic gapping, as elongation did not differ between the nonaugmented and augmented repairs (0.5 mm vs 0.7 mm; P = .276) and was small relative to the nearly 4 mm of construct gapping. Gapping may be affected by healing and integration of the mesh into the repaired tendon over time, but this effect could not be captured in the present study. Patients are initially immobilized and passive shoulder motion gradually introduced, in stark contrast to the immediate loading protocol in the present study. Regardless, the 25% increase in overall strength may be clinically important, especially in cases of difficult repair or poor tissue quality.

Our technique simplifies arthroscopic augmentation—stitches are passed through the rotator cuff in simple fashion. Before being tied, the limbs that were passed through the rotator cuff are removed through a cannula and then passed through the synthetic graft.

The graft is then shuttled into the subacromial space, and all the suture limbs are tied simply (Figures 5A, 5B). Even though this implementation is simple, our data showed the construct increases overall failure loads by about 25% with no effect on construct elongation.

 

Study Limitations

This study had several limitations. First, it was a cadaveric biomechanical study that evaluated only time-zero biomechanical properties. Loads were normalized to tendon size, specimens were randomized between sides, and paired specimens were used to minimize the effects of tendon and bone quality on outcome metrics. In addition, donor tendons were representative of otherwise healthy tissue. Chronic tears and associated resorption/atrophy could have affected the magnitude of forces and gapping detected in this study. Theoretically, over time the tendon tissue will adhere to and grow into the mesh, which could minimize potential differences. Studies are needed to determine the effects of healing on long-term repair strength in affected patients. Last, all constructs were performed in open fashion to improve repeatability of construct placement and provide accessibility for Instron testing. Our technique did not directly replicate the arthroscopic approach, but, unlike other augmentation techniques, it is so simple that transition to all-arthroscopic augmentation is realistic.

Patch augmentation increases the cost of materials and operative time and should be considered a limitation of its utility. We do not recommend augmentation in all RCRs, as it likely is cost-ineffective. Instead, we recommend augmentation in cases of poor tissue quality, which could lead to healing failure, revision surgery, and higher overall patient costs beyond the cost of adding augmentation. Similarly, we recommend augmentation for revision cases in which tendon healing has failed and tissue quality is poor. The goal is to prevent another failure.

Conclusion

PHA graft augmentation of single-row triple-loaded anchor repairs of the supraspinatus tendon improves the overall ultimate load to failure by 25%. There was no difference in gap formation after cyclic loading between augmented and nonaugmented repairs. This technique for arthroscopic augmentation can be used to improve initial biomechanical repair strength in tears at risk for failure.

Am J Orthop. 2016;45(7):E527-E533. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Healing after rotator cuff repair (RCR) can be challenging, especially in cases of large and massive tears, revision repairs, and tendons with poor tissue quality.^1-3 Poor tissue quality is associated with increased risk for recurrent tears, independent of age and tear size.³ Various techniques have been used to improve tendon fixation strength in these difficult situations, including augmented suture configurations (eg, massive cuff stitches, rip-stop stitches) and tissue grafts (eg, acellular dermal matrix).^4-9 Clinical studies have found improved healing rates for larger tears and revision repairs using acellular dermal matrix grafts.^6,10 Synthetic patches are another option for RCR augmentation, but limited clinical data and biomechanical evidence support use of synthetic grafts as an augment for RCRs.^11-13

Polyhydroxyalkanoates (PHAs) are a class of biodegradable polymers that have been used as orthopedic devices, tissue scaffolds, patches, and other applications with increasing frequency over the past decade.¹⁴ In the laboratory, these implanted materials have been shown to support cell migration and growth.¹⁵ The PHA family of polymers typically degrades by hydrolytic and bacterial depolymerase mechanisms over 52-plus weeks in vivo.¹⁴PHA grafts have been studied in the setting of RCR. An expanded polytetrafluoroethylene scaffold was shown to improve repair mechanics when used as a bursal side graft in an in vitro ovine model.¹¹ The graft increased tendon footprint contact pressure and failure loads by almost 180 N. In clinical studies, poly-L-lactic acid augmentations have been used to reinforce massive RCRs. Lenart and colleagues¹⁶ found that 38% of 16 patients with such tears had an intact rotator cuff at 1.2-year follow-up, and improvement in clinical scores. Proctor¹³ reported on use of a poly-L-lactic acid retrograde patch for reinforcement of massive tears with both single- and double-row repairs in 18 patients. The cohort had more favorable rates of intact cuffs at 12 months (83%) and 42 months (78%), and ASES (American Shoulder and Elbow Surgeons) scores improved from 25 before surgery to 82 at latest follow-up after surgery.

RCR augmentation traditionally has been performed with an open or mini-open technique.⁶ Recently, several authors have reported on arthroscopic techniques for augmentation with either acellular dermal matrix or synthetic grafts.^13,17,18 Most techniques have involved “bridging” with a graft or patch used to stress-shield a single-row repair.^8,9,13 This bridging typically involves placing several sutures medial to where the anchor repair stitches pass through the tendon. An alternative is to pass the repair stitches through both the tendon and the graft.^17-19 The overall volume of tissue incorporated into the repair stitches (rotator cuff plus graft) is increased with the augmented technique relative to the bridging technique. Both can be technically challenging, but the augmented technique may be easier to perform arthroscopically.^9,19 Regardless, these techniques are complicated and require a higher level of arthroscopic skills compared with those required in arthroscopic RCR without a graft. Simplifying arthroscopic graft augmentation likely will increase its utility because, even for skilled surgeons, adding a graft can increase operative time by 20 to 30 minutes. Simplification will also extend use of the technique to surgeons with less experience and proficiency with arthroscopic repair.

We developed a simple method for augmenting single-row RCR with a strip of bioresorbable soft-tissue scaffold. We also conducted a study to evaluate the initial biomechanical properties of single-row RCR in cadaveric shoulder specimens augmented with PHA mesh (BioFiber; Tornier) graft as compared with single-row RCR without augmentation. Both cyclic gap formation and ultimate failure loads and displacement were quantified. We hypothesized that the augmented RCRs would have decreased gap formation and increased ultimate failure loads compared with nonaugmented RCRs. This study was exempt from having to obtain Institutional Review Board approval.

Methods

Eight pairs of fresh-frozen cadaver humeri (6 male, 2 female; mean [SD] age, 61 [9] years) were dissected of all soft tissue (except rotator cuff) by Dr. Tashjian, a board-certified, fellowship-trained orthopedic surgeon. There were no qualitative differences in tendon condition between tendons within a pair. The supraspinatus muscle and tendon were separated from the other rotator cuff muscles. The infraspinatus, subscapularis, and teres minor were removed from the humerus. Last, the supraspinatus was resected at its insertion. Humeral pairs were then randomized into augmented and nonaugmented RCRs within each pair.

In the nonaugmented group, the supraspinatus was reattached to its insertion in a single-row RCR with 2 triple-loaded suture anchors (5.5-mm Insite FT Ti, No. 2 Force Fiber suture; Tornier) and 6 simple stitches (Figure 1A). Anchors were placed midway between the articular margin and the lateral edge of the greater tuberosity at about 45° to the bone surface.

Anchors were separated by 15 mm, with the anterior anchor 5 mm posterior to the biceps groove. Stitches were passed through the supraspinatus tendon, taking a 15-mm bite of tissue, with each stitch separated by 5 mm. Each suture was then tied with a Revo knot.

In the contralateral shoulders, augmented RCRs were performed. Specimens were prepared exactly as they were for the nonaugmented RCRs, including anchor placement and suture passage. Before knot tying, RCRs were augmented with 2 strips of 13-mm × 23-mm PHA mesh (BioFiber) (Figure 1B). One strip was used to augment the 3 sutures of each anchor, overlying the residual tendon, to reinforce the tendon–knot interface. After each suture was passed through the supraspinatus tendon from the intra-articular surface, the stitch was passed through the strip of PHA mesh. Stitches were separated by 5 mm in each mesh strip. All 6 sutures were then tied with a Revo knot between the free end of each suture leg and the leg that passed through the tendon and mesh.

Each humerus was transected at the midshaft and potted and mounted in an Instron 1331 load frame with Model 8800 controller (Instron). A cryoclamp was used to grasp the supraspinatus muscle belly above the musculotendinous junction (Figure 2).

The humerus was aligned in the mounting fixture such that loading was performed at a 135° angle with the humeral shaft (Figure 2).²⁰ The Instron, which was equipped with a 1-kN load cell (Dynacell Model 2527-130; Instron) to monitor applied force, measured applied displacement.

Three rows of 2-mm fiducial markers were affixed to the bone, tendon, and muscle belly with cyanoacrylate for tracking with a digital video system (DMAS Version 6.5; Spicatek) (Figure 3).21

Camera resolution was 1360 pixels × 1024 pixels, and DMAS accuracy for marker centroid tracking was rated at ± 0.005 mm. Construct gapping was defined as the difference in displacement between the markers at the tissue–suture interface and the markers on the bone. Tissue deformation was then defined as the displacement between the markers at the tissue–suture interface and the markers on the muscle belly. Mean gapping was defined from anterior to posterior across the construct using 3 sets of fiducial markers.

A 0.1-MPa pre-stress (applied force/tendon cross-sectional area) was applied to each construct to determine the starting position for the deformation profile. Each repair underwent 1000 cycles of uniaxial load-controlled displacement between 0.1 and 1.0 MPa of effective stress at 1 Hz. Effective stress was determined as the ratio of applied force to cross-sectional area of the tendon at harvest to normalize the applied loads between tendons of varying size. During cyclic testing, gapping of more than 5 mm was defined as construct failure.²² After cyclic loading, each construct was loaded to failure at 1.0 mm/s. Ultimate failure load was defined as the highest load achieved at the maximum displacement before rapid decline in load supported by the construct.

 

Statistical Analysis

Paired t tests were used to compare the matched pairs of constructs. For all tests, significance was set at P ≤ .05. Post hoc power was calculated for significant results using G*Power Version 3.1.6.²³ All data are presented as means (SDs).

Results

After 1000 cycles of displacement, mean (SD) gapping was 3.8 (0.9) mm for the nonaugmented repairs and 3.9 (1.1) mm for the PHA mesh–augmented repairs (P = .879) (Figure 4).

Mean (SD) tissue elongation above the construct was comparable (P = .276) between nonaugmented repairs, 0.5 (0.4) mm, and augmented repairs, 0.7 (0.4) mm. No specimens failed during cyclic load, as mean gapping was <4 mm²² in all constructs. Mean (SD) applied force was 11.8 (1.8) N at 0.1 MPa of effective stress and 117.8 (18.1) N at 1.0 MPa of effective stress. Applied force did not vary between constructs (P = .727).

For the nonaugmented repairs, mean (SD) failure displacement was 6.3 (1.7) mm, and mean (SD) ultimate failure load was 472.1 (120.3) N. For the PHA-augmented repairs, failure displacement was 5.5 (1.9) mm, and ultimate failure load was 571.2 (173.0) N. There was no difference in failure displacement (P = .393), but there was a difference in ultimate failure load (P = .042; power = 0.57). During failure testing, mean (SD) tissue deformation was higher (P = .012; power = 0.83) for the PHA-augmented repairs, 1.2 (0.7) mm, than for the nonaugmented repairs, 0.8 (0.5) mm. Failures, which were consistent within pairs, were caused by tissue failure, with sutures pulling through the tissue (4 pairs) or single anchor pullout before ultimate tissue failure (4 pairs). Of the 4 failures with anchor pullout, 3 had anterior anchor pullout, and 1 had posterior anchor pullout. In all specimens with anchor pullout, the second anchor remained stable, and ultimate failure occurred with tissue tearing at the suture interface. There were no significant differences in any metrics between specimens that failed with intact anchors and specimens with single anchor pullout (P ≥ .122). Therefore, both groups were pooled for the failure analysis.

Discussion

RCR augmentation with a synthetic graft is a viable option for improving fixation strength of supraspinatus repairs, as shown in otherwise healthy tendon in the present study. Our hypothesis that there would be decreased gap formation with graft augmentation was not supported, whereas the hypothesis of increased failure loads with graft augmentation was supported. These findings may also be applicable in cases of large tears, revisions, and tendons with poor tissue quality. Simplification of graft application techniques will allow quick and easy arthroscopic augmentation.

Studies of RCRs for large or massive tears have reported retear rates of 25% to 79%.^24-26 Latissimus dorsi tendon transfers also show promise in posterosuperior RCRs, with failure rates near 10%.^27,28 Although use of PHA patches in RCR augmentation is relatively new, short-term and midterm failure rates are in the range of 20% to 60% in the few small cohorts currently being studied.^13,16 It is possible that these rates may improve as indications, surgical experience, and techniques for use of PHA patches are further refined. Regardless, with PHA currently being used in practice, it is important to quantify the biomechanics of the augmentation as a baseline for its performance in reinforcing the tendon–suture interface.

We determined that the initial fixation strength of single-row repairs was higher with the addition of PHA synthetic grafts using a very simple technique. Single-row triple-loaded anchor repairs already provide high initial mechanical strength, and our results are similar to those of another study of this technique.²⁹ Despite the already high mechanical strength of a triple-loaded anchor repair, PHA mesh increased ultimate strength by about 100 N (~25%). Of note, tissue elongation during failure was higher (P = .012; power = 0.83) in the PHA-augmented group (1.2 mm) than in the nonaugmented group (0.8 mm). This was not surprising—failure loads were almost 100 N higher in the PHA-augmented group than in the nonaugmented group. Consequently, much higher forces were placed on the muscle belly, likely resulting in additional elongation of the intact tissue medial to the repair construct.

The ultimate failure loads in our study compare favorably with the biomechanical strength of augmented repairs reported by others.^8,9,18 Barber and colleagues¹⁸ evaluated an augmented single-row repair with 2 double-loaded suture anchors and an acellular dermal matrix graft. The ultimate failure load of the augmented repairs was 325 N. In contrast, Omae and colleagues⁸ tested a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft. Ultimate failure load of the augmented repairs was 560 N, similar to our finding. Last, Shea and colleagues⁹ evaluated a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft, with ultimate failure load of 429 N. The techniques in all 3 studies can be performed arthroscopically but are challenging and require multiple extra sutures and anchors that need management and tying. Our technique provides similar initial fixation strength, has no requirement for extra sutures or anchors, and is very simple to perform.

The supraspinatus tendon is estimated to fail between 800 N and 1000 N.^30,31 Biomechanical shoulder simulators use supraspinatus forces in the range of 20 N to 200 N for scapular plane abduction.^32-36 Therefore, the single-row repair failures in our study fell between functional and full-thickness failure loads. Studies on the mechanics of degenerated human supraspinatus tendon are limited, but there is evidence the mechanical properties of these tissues are inferior to those of healthy tendon.³⁷ A 100-N increase in failure loads with PHA augmentation may prove highly significant in reinforcing the suture–tendon interface in degenerated tendons.

Adding the mesh did not have any effect on gapping at the repair site after cyclic loading. This finding suggests that construct gapping under cyclic loading is not a function of a reinforced knot–tendon interface but is instead caused by microtearing and cinching of the suture constructs in relation to the underlying bone. Tissue elongation likely was not a strong contributor to overall cyclic gapping, as elongation did not differ between the nonaugmented and augmented repairs (0.5 mm vs 0.7 mm; P = .276) and was small relative to the nearly 4 mm of construct gapping. Gapping may be affected by healing and integration of the mesh into the repaired tendon over time, but this effect could not be captured in the present study. Patients are initially immobilized and passive shoulder motion gradually introduced, in stark contrast to the immediate loading protocol in the present study. Regardless, the 25% increase in overall strength may be clinically important, especially in cases of difficult repair or poor tissue quality.

Our technique simplifies arthroscopic augmentation—stitches are passed through the rotator cuff in simple fashion. Before being tied, the limbs that were passed through the rotator cuff are removed through a cannula and then passed through the synthetic graft.

The graft is then shuttled into the subacromial space, and all the suture limbs are tied simply (Figures 5A, 5B). Even though this implementation is simple, our data showed the construct increases overall failure loads by about 25% with no effect on construct elongation.

 

Study Limitations

This study had several limitations. First, it was a cadaveric biomechanical study that evaluated only time-zero biomechanical properties. Loads were normalized to tendon size, specimens were randomized between sides, and paired specimens were used to minimize the effects of tendon and bone quality on outcome metrics. In addition, donor tendons were representative of otherwise healthy tissue. Chronic tears and associated resorption/atrophy could have affected the magnitude of forces and gapping detected in this study. Theoretically, over time the tendon tissue will adhere to and grow into the mesh, which could minimize potential differences. Studies are needed to determine the effects of healing on long-term repair strength in affected patients. Last, all constructs were performed in open fashion to improve repeatability of construct placement and provide accessibility for Instron testing. Our technique did not directly replicate the arthroscopic approach, but, unlike other augmentation techniques, it is so simple that transition to all-arthroscopic augmentation is realistic.

Patch augmentation increases the cost of materials and operative time and should be considered a limitation of its utility. We do not recommend augmentation in all RCRs, as it likely is cost-ineffective. Instead, we recommend augmentation in cases of poor tissue quality, which could lead to healing failure, revision surgery, and higher overall patient costs beyond the cost of adding augmentation. Similarly, we recommend augmentation for revision cases in which tendon healing has failed and tissue quality is poor. The goal is to prevent another failure.

Conclusion

PHA graft augmentation of single-row triple-loaded anchor repairs of the supraspinatus tendon improves the overall ultimate load to failure by 25%. There was no difference in gap formation after cyclic loading between augmented and nonaugmented repairs. This technique for arthroscopic augmentation can be used to improve initial biomechanical repair strength in tears at risk for failure.

Am J Orthop. 2016;45(7):E527-E533. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Healing after rotator cuff repair (RCR) can be challenging, especially in cases of large and massive tears, revision repairs, and tendons with poor tissue quality.^1-3 Poor tissue quality is associated with increased risk for recurrent tears, independent of age and tear size.³ Various techniques have been used to improve tendon fixation strength in these difficult situations, including augmented suture configurations (eg, massive cuff stitches, rip-stop stitches) and tissue grafts (eg, acellular dermal matrix).^4-9 Clinical studies have found improved healing rates for larger tears and revision repairs using acellular dermal matrix grafts.^6,10 Synthetic patches are another option for RCR augmentation, but limited clinical data and biomechanical evidence support use of synthetic grafts as an augment for RCRs.^11-13

Polyhydroxyalkanoates (PHAs) are a class of biodegradable polymers that have been used as orthopedic devices, tissue scaffolds, patches, and other applications with increasing frequency over the past decade.¹⁴ In the laboratory, these implanted materials have been shown to support cell migration and growth.¹⁵ The PHA family of polymers typically degrades by hydrolytic and bacterial depolymerase mechanisms over 52-plus weeks in vivo.¹⁴PHA grafts have been studied in the setting of RCR. An expanded polytetrafluoroethylene scaffold was shown to improve repair mechanics when used as a bursal side graft in an in vitro ovine model.¹¹ The graft increased tendon footprint contact pressure and failure loads by almost 180 N. In clinical studies, poly-L-lactic acid augmentations have been used to reinforce massive RCRs. Lenart and colleagues¹⁶ found that 38% of 16 patients with such tears had an intact rotator cuff at 1.2-year follow-up, and improvement in clinical scores. Proctor¹³ reported on use of a poly-L-lactic acid retrograde patch for reinforcement of massive tears with both single- and double-row repairs in 18 patients. The cohort had more favorable rates of intact cuffs at 12 months (83%) and 42 months (78%), and ASES (American Shoulder and Elbow Surgeons) scores improved from 25 before surgery to 82 at latest follow-up after surgery.

RCR augmentation traditionally has been performed with an open or mini-open technique.⁶ Recently, several authors have reported on arthroscopic techniques for augmentation with either acellular dermal matrix or synthetic grafts.^13,17,18 Most techniques have involved “bridging” with a graft or patch used to stress-shield a single-row repair.^8,9,13 This bridging typically involves placing several sutures medial to where the anchor repair stitches pass through the tendon. An alternative is to pass the repair stitches through both the tendon and the graft.^17-19 The overall volume of tissue incorporated into the repair stitches (rotator cuff plus graft) is increased with the augmented technique relative to the bridging technique. Both can be technically challenging, but the augmented technique may be easier to perform arthroscopically.^9,19 Regardless, these techniques are complicated and require a higher level of arthroscopic skills compared with those required in arthroscopic RCR without a graft. Simplifying arthroscopic graft augmentation likely will increase its utility because, even for skilled surgeons, adding a graft can increase operative time by 20 to 30 minutes. Simplification will also extend use of the technique to surgeons with less experience and proficiency with arthroscopic repair.

We developed a simple method for augmenting single-row RCR with a strip of bioresorbable soft-tissue scaffold. We also conducted a study to evaluate the initial biomechanical properties of single-row RCR in cadaveric shoulder specimens augmented with PHA mesh (BioFiber; Tornier) graft as compared with single-row RCR without augmentation. Both cyclic gap formation and ultimate failure loads and displacement were quantified. We hypothesized that the augmented RCRs would have decreased gap formation and increased ultimate failure loads compared with nonaugmented RCRs. This study was exempt from having to obtain Institutional Review Board approval.

Methods

Eight pairs of fresh-frozen cadaver humeri (6 male, 2 female; mean [SD] age, 61 [9] years) were dissected of all soft tissue (except rotator cuff) by Dr. Tashjian, a board-certified, fellowship-trained orthopedic surgeon. There were no qualitative differences in tendon condition between tendons within a pair. The supraspinatus muscle and tendon were separated from the other rotator cuff muscles. The infraspinatus, subscapularis, and teres minor were removed from the humerus. Last, the supraspinatus was resected at its insertion. Humeral pairs were then randomized into augmented and nonaugmented RCRs within each pair.

In the nonaugmented group, the supraspinatus was reattached to its insertion in a single-row RCR with 2 triple-loaded suture anchors (5.5-mm Insite FT Ti, No. 2 Force Fiber suture; Tornier) and 6 simple stitches (Figure 1A). Anchors were placed midway between the articular margin and the lateral edge of the greater tuberosity at about 45° to the bone surface.

Anchors were separated by 15 mm, with the anterior anchor 5 mm posterior to the biceps groove. Stitches were passed through the supraspinatus tendon, taking a 15-mm bite of tissue, with each stitch separated by 5 mm. Each suture was then tied with a Revo knot.

In the contralateral shoulders, augmented RCRs were performed. Specimens were prepared exactly as they were for the nonaugmented RCRs, including anchor placement and suture passage. Before knot tying, RCRs were augmented with 2 strips of 13-mm × 23-mm PHA mesh (BioFiber) (Figure 1B). One strip was used to augment the 3 sutures of each anchor, overlying the residual tendon, to reinforce the tendon–knot interface. After each suture was passed through the supraspinatus tendon from the intra-articular surface, the stitch was passed through the strip of PHA mesh. Stitches were separated by 5 mm in each mesh strip. All 6 sutures were then tied with a Revo knot between the free end of each suture leg and the leg that passed through the tendon and mesh.

Each humerus was transected at the midshaft and potted and mounted in an Instron 1331 load frame with Model 8800 controller (Instron). A cryoclamp was used to grasp the supraspinatus muscle belly above the musculotendinous junction (Figure 2).

The humerus was aligned in the mounting fixture such that loading was performed at a 135° angle with the humeral shaft (Figure 2).²⁰ The Instron, which was equipped with a 1-kN load cell (Dynacell Model 2527-130; Instron) to monitor applied force, measured applied displacement.

Three rows of 2-mm fiducial markers were affixed to the bone, tendon, and muscle belly with cyanoacrylate for tracking with a digital video system (DMAS Version 6.5; Spicatek) (Figure 3).21

Camera resolution was 1360 pixels × 1024 pixels, and DMAS accuracy for marker centroid tracking was rated at ± 0.005 mm. Construct gapping was defined as the difference in displacement between the markers at the tissue–suture interface and the markers on the bone. Tissue deformation was then defined as the displacement between the markers at the tissue–suture interface and the markers on the muscle belly. Mean gapping was defined from anterior to posterior across the construct using 3 sets of fiducial markers.

A 0.1-MPa pre-stress (applied force/tendon cross-sectional area) was applied to each construct to determine the starting position for the deformation profile. Each repair underwent 1000 cycles of uniaxial load-controlled displacement between 0.1 and 1.0 MPa of effective stress at 1 Hz. Effective stress was determined as the ratio of applied force to cross-sectional area of the tendon at harvest to normalize the applied loads between tendons of varying size. During cyclic testing, gapping of more than 5 mm was defined as construct failure.²² After cyclic loading, each construct was loaded to failure at 1.0 mm/s. Ultimate failure load was defined as the highest load achieved at the maximum displacement before rapid decline in load supported by the construct.

 

Statistical Analysis

Paired t tests were used to compare the matched pairs of constructs. For all tests, significance was set at P ≤ .05. Post hoc power was calculated for significant results using G*Power Version 3.1.6.²³ All data are presented as means (SDs).

Results

After 1000 cycles of displacement, mean (SD) gapping was 3.8 (0.9) mm for the nonaugmented repairs and 3.9 (1.1) mm for the PHA mesh–augmented repairs (P = .879) (Figure 4).

Mean (SD) tissue elongation above the construct was comparable (P = .276) between nonaugmented repairs, 0.5 (0.4) mm, and augmented repairs, 0.7 (0.4) mm. No specimens failed during cyclic load, as mean gapping was <4 mm²² in all constructs. Mean (SD) applied force was 11.8 (1.8) N at 0.1 MPa of effective stress and 117.8 (18.1) N at 1.0 MPa of effective stress. Applied force did not vary between constructs (P = .727).

For the nonaugmented repairs, mean (SD) failure displacement was 6.3 (1.7) mm, and mean (SD) ultimate failure load was 472.1 (120.3) N. For the PHA-augmented repairs, failure displacement was 5.5 (1.9) mm, and ultimate failure load was 571.2 (173.0) N. There was no difference in failure displacement (P = .393), but there was a difference in ultimate failure load (P = .042; power = 0.57). During failure testing, mean (SD) tissue deformation was higher (P = .012; power = 0.83) for the PHA-augmented repairs, 1.2 (0.7) mm, than for the nonaugmented repairs, 0.8 (0.5) mm. Failures, which were consistent within pairs, were caused by tissue failure, with sutures pulling through the tissue (4 pairs) or single anchor pullout before ultimate tissue failure (4 pairs). Of the 4 failures with anchor pullout, 3 had anterior anchor pullout, and 1 had posterior anchor pullout. In all specimens with anchor pullout, the second anchor remained stable, and ultimate failure occurred with tissue tearing at the suture interface. There were no significant differences in any metrics between specimens that failed with intact anchors and specimens with single anchor pullout (P ≥ .122). Therefore, both groups were pooled for the failure analysis.

Discussion

RCR augmentation with a synthetic graft is a viable option for improving fixation strength of supraspinatus repairs, as shown in otherwise healthy tendon in the present study. Our hypothesis that there would be decreased gap formation with graft augmentation was not supported, whereas the hypothesis of increased failure loads with graft augmentation was supported. These findings may also be applicable in cases of large tears, revisions, and tendons with poor tissue quality. Simplification of graft application techniques will allow quick and easy arthroscopic augmentation.

Studies of RCRs for large or massive tears have reported retear rates of 25% to 79%.^24-26 Latissimus dorsi tendon transfers also show promise in posterosuperior RCRs, with failure rates near 10%.^27,28 Although use of PHA patches in RCR augmentation is relatively new, short-term and midterm failure rates are in the range of 20% to 60% in the few small cohorts currently being studied.^13,16 It is possible that these rates may improve as indications, surgical experience, and techniques for use of PHA patches are further refined. Regardless, with PHA currently being used in practice, it is important to quantify the biomechanics of the augmentation as a baseline for its performance in reinforcing the tendon–suture interface.

We determined that the initial fixation strength of single-row repairs was higher with the addition of PHA synthetic grafts using a very simple technique. Single-row triple-loaded anchor repairs already provide high initial mechanical strength, and our results are similar to those of another study of this technique.²⁹ Despite the already high mechanical strength of a triple-loaded anchor repair, PHA mesh increased ultimate strength by about 100 N (~25%). Of note, tissue elongation during failure was higher (P = .012; power = 0.83) in the PHA-augmented group (1.2 mm) than in the nonaugmented group (0.8 mm). This was not surprising—failure loads were almost 100 N higher in the PHA-augmented group than in the nonaugmented group. Consequently, much higher forces were placed on the muscle belly, likely resulting in additional elongation of the intact tissue medial to the repair construct.

The ultimate failure loads in our study compare favorably with the biomechanical strength of augmented repairs reported by others.^8,9,18 Barber and colleagues¹⁸ evaluated an augmented single-row repair with 2 double-loaded suture anchors and an acellular dermal matrix graft. The ultimate failure load of the augmented repairs was 325 N. In contrast, Omae and colleagues⁸ tested a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft. Ultimate failure load of the augmented repairs was 560 N, similar to our finding. Last, Shea and colleagues⁹ evaluated a bridging single-row repair using 2 double-loaded suture anchors and an acellular dermal matrix graft, with ultimate failure load of 429 N. The techniques in all 3 studies can be performed arthroscopically but are challenging and require multiple extra sutures and anchors that need management and tying. Our technique provides similar initial fixation strength, has no requirement for extra sutures or anchors, and is very simple to perform.

The supraspinatus tendon is estimated to fail between 800 N and 1000 N.^30,31 Biomechanical shoulder simulators use supraspinatus forces in the range of 20 N to 200 N for scapular plane abduction.^32-36 Therefore, the single-row repair failures in our study fell between functional and full-thickness failure loads. Studies on the mechanics of degenerated human supraspinatus tendon are limited, but there is evidence the mechanical properties of these tissues are inferior to those of healthy tendon.³⁷ A 100-N increase in failure loads with PHA augmentation may prove highly significant in reinforcing the suture–tendon interface in degenerated tendons.

Adding the mesh did not have any effect on gapping at the repair site after cyclic loading. This finding suggests that construct gapping under cyclic loading is not a function of a reinforced knot–tendon interface but is instead caused by microtearing and cinching of the suture constructs in relation to the underlying bone. Tissue elongation likely was not a strong contributor to overall cyclic gapping, as elongation did not differ between the nonaugmented and augmented repairs (0.5 mm vs 0.7 mm; P = .276) and was small relative to the nearly 4 mm of construct gapping. Gapping may be affected by healing and integration of the mesh into the repaired tendon over time, but this effect could not be captured in the present study. Patients are initially immobilized and passive shoulder motion gradually introduced, in stark contrast to the immediate loading protocol in the present study. Regardless, the 25% increase in overall strength may be clinically important, especially in cases of difficult repair or poor tissue quality.

Our technique simplifies arthroscopic augmentation—stitches are passed through the rotator cuff in simple fashion. Before being tied, the limbs that were passed through the rotator cuff are removed through a cannula and then passed through the synthetic graft.

The graft is then shuttled into the subacromial space, and all the suture limbs are tied simply (Figures 5A, 5B). Even though this implementation is simple, our data showed the construct increases overall failure loads by about 25% with no effect on construct elongation.

 

Study Limitations

This study had several limitations. First, it was a cadaveric biomechanical study that evaluated only time-zero biomechanical properties. Loads were normalized to tendon size, specimens were randomized between sides, and paired specimens were used to minimize the effects of tendon and bone quality on outcome metrics. In addition, donor tendons were representative of otherwise healthy tissue. Chronic tears and associated resorption/atrophy could have affected the magnitude of forces and gapping detected in this study. Theoretically, over time the tendon tissue will adhere to and grow into the mesh, which could minimize potential differences. Studies are needed to determine the effects of healing on long-term repair strength in affected patients. Last, all constructs were performed in open fashion to improve repeatability of construct placement and provide accessibility for Instron testing. Our technique did not directly replicate the arthroscopic approach, but, unlike other augmentation techniques, it is so simple that transition to all-arthroscopic augmentation is realistic.

Patch augmentation increases the cost of materials and operative time and should be considered a limitation of its utility. We do not recommend augmentation in all RCRs, as it likely is cost-ineffective. Instead, we recommend augmentation in cases of poor tissue quality, which could lead to healing failure, revision surgery, and higher overall patient costs beyond the cost of adding augmentation. Similarly, we recommend augmentation for revision cases in which tendon healing has failed and tissue quality is poor. The goal is to prevent another failure.

Conclusion

PHA graft augmentation of single-row triple-loaded anchor repairs of the supraspinatus tendon improves the overall ultimate load to failure by 25%. There was no difference in gap formation after cyclic loading between augmented and nonaugmented repairs. This technique for arthroscopic augmentation can be used to improve initial biomechanical repair strength in tears at risk for failure.

Am J Orthop. 2016;45(7):E527-E533. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Acute ankle injuries are common problems treated by orthopedic surgeons. In the United States, nearly 2 million ankle sprains occur each year,¹ and ankle fractures account for 9% to 18% of all fractures treated in emergency departments.^2,3 Ankle injuries that involve the syndesmotic ligaments may result in instability and require specific treatment beyond fixation of the malleolar fractures.

The usual mechanism of syndesmotic injury is external rotation of the ankle with hyperdorsiflexion of a pronated or supinated foot.^4,5 Syndesmotic injuries are estimated to occur in up to 10% of ankle sprains⁶ and up to 23% of all ankle fractures.⁷ Overall US incidence of syndesmotic injury is estimated at 6445 injuries per year.⁸ Syndesmotic injury occurs in 39% to 45% of supination-external rotation IV ankle fractures.^9,10 Pronation-external rotation ankle fractures have the highest rate of syndesmotic injury. Syndesmotic injury may be less common in other types of malleolar fracture, but the exact incidence has not been reliably reported.

Traditionally, isolated nondisplaced syndesmotic injuries are treated nonoperatively, and syndesmotic injuries with concomitant malleolar fractures are treated surgically. Various options are available for syndesmotic fixation. The gold standard is syndesmotic screw placement from the lateral aspect of the fibula through the tibia. Fixation may be achieved with screws in a variety of configurations and formats. However, fixation with two 4.5-mm screws is stronger.^11,12 Functional outcomes are similar, regardless of screw material,^13-16 number of cortices,¹⁷ or number of screws.¹⁸ Disadvantages specific to screw fixation include altered ankle biomechanics,^19,20 potential for screw breakage,²¹ and need for implant removal.³Alternatively, suture button fixation is said to be equally as effective as screw fixation in achieving syndesmotic reduction, and their functional outcomes are similar.^22,23 The initial cost of suture button fixation is higher than that of screw fixation, but the difference may be offset by potential elimination of a second surgery for syndesmotic screw removal.²⁴ Soft-tissue irritation caused by the suture material and local osteolysis are reported complications of suture button fixation.^25-27

Regardless of fixation method used, achieving anatomical reduction of the syndesmosis is considered the most important factor in optimizing functional outcomes.^28-31 However, achieving and verifying anatomical reduction of the syndesmosis during surgery can be quite challenging.^30,32-34 Various methods of lowering the malreduction risk, including direct visualization of the tibiofibular joint during reduction^30,35 and intraoperative 3-dimensional imaging,^33,36 have been proposed.

In the study reported here, we used a US insurance database to determine the incidence and rate of syndesmotic stabilization within various ankle injuries and fracture patterns.

Materials and Methods

All data for this study were obtained from a publicly available for-fee healthcare database, the PearlDiver Patient Records Database, which includes procedural volumes and demographic information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the study were derived from 2 databases within PearlDiver: a private-payer database, which has its largest contribution (>30 million individual patient records for 2007-2011) from United HealthCare, and a Medicare database (>50 million patient records for 2007-2011). Access to the database was granted by PearlDiver Technologies for the purpose of academic research. The database was stored on a password-protected server maintained by PearlDiver.

We searched the database for cases of ankle fracture fixation, including fixation of isolated lateral malleolus (CPT 27792), bimalleolar (CPT 27814), and trimalleolar (CPTs 27822 and 27823) fractures. CPT 27829 was used to search for syndesmotic fixation, and CPT 20680 for implant removal. These codes were used individually and in combination.

Overall procedural volume data are reported as number of patients with the given CPT(s) in the database output and as incidence, calculated as number of patients with the CPT of interest normalized to total number of patients in the database for that particular subgroup. Results of age group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who had the CPT procedure of interest that year. As United HealthCare is the largest contributor to the private-payer portion of the database and is represented most prominently in the southern region, data for the regional analysis are presented only as incidence. This incidence was calculated as number of patients in a particular region and year normalized to total number of patients in the database for that region or year. The regions were Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MI, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-square linear-by-linear association analysis was used to determine the statistical significance of time trends in procedural volume, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

 

Results

Number of open reduction and internal fixation (ORIF) procedures increased for all ankle fracture types over the period 2007 to 2011 (Table 1).

Over the same period, number of procedures for isolated syndesmosis ORIF increased significantly (P = .045), by 18%, and the rate of syndesmotic fixation with ORIF of ankle fracture significantly increased for all ankle fracture types (Ps < .0001 for ORIF of lateral malleolus, bimalleolar, and trimalleolar fractures) (Figure).

The largest percentage change (43%) was in the rate of syndesmotic fixation with ORIF of a bimalleolar ankle fracture. The rate of implant removal after syndesmotic fixation significantly decreased for all types of ankle fracture, including those that required only syndesmotic fixation. The largest percentage decrease (32.8%) in implant removal was in the rate of ORIF of a lateral malleolus fracture with syndesmotic fixation (P = .002).

ORIF was performed for an ankle injury in 54,767 patients during the period 2007 to 2011, resulting in a cumulative incidence of 64.2 per 1000 patients (Table 2).

Total number of ankle ORIF procedures increased with each decade of life until age 80 years. Incidence of ankle ORIF was highest for patients 20 years old to 29 years old (151.6/1000 patients). Incidence notably decreased in patients 60 years old to 69 years old (69.1/1000 patients) compared with patients 50 years old to 59 years old (149.5/1000 patients). Lateral malleolus fractures were the most common ankle fractures for every age group until the 50 to 59 year decade, at which point bimalleolar fractures became most common. In all age groups, trimalleolar fractures were the least common ankle fractures.

More ankle ORIF procedures were performed in females (33,565) than in males (21,202); incidence of ankle ORIF procedures was higher in females (68.6/1000 patients) than in males (58.4/1000 patients) (Table 2); percentages of bimalleolar and trimalleolar fractures were higher in females (bi, 40.6%; tri, 27.8%) than in males (bi, 34.6%; tri, 15.2%); and percentage of lateral malleolus fractures was higher in males (50.2%) than in females (31.6%).

Incidence of ankle ORIF procedures was similar in the South (69.6/1000 patients), Midwest (69.4/100 patients), and West (65.1/1000 patients) but lower in the Northeast (43.3/1000 patients) (Table 2). Lateral malleolus fractures were the most common ankle fractures in the Midwest (40.7%) and West (41.3%), followed by bimalleolar fractures (Midwest, 36.3%; West 36.0%) and trimalleolar fractures (Midwest, 23.0%; West, 22.7%). Bimalleolar fractures were most common in the Northeast (40.2%) and South (39.8%), followed by lateral malleolus fractures (Northeast, 34.4%; South, 38.0%) and trimalleolar fractures (Northeast, 25.4%; South, 22.3%).

Discussion

The present study found no significant change in number of lateral malleolus, bimalleolar, and trimalleolar ankle fracture ORIF procedures performed over the period 2007 to 2011. However, over the same period, incidence of syndesmosis fixation increased significantly in patients with isolated syndesmotic injuries and in patients with concomitant ankle fracture and syndesmotic injury. The largest percentage change was found in the bimalleolar ORIF group, which showed nearly a doubling of syndesmotic fixation over the 4-year study period, followed by a 38.1% increase in syndesmotic fixation in the trimalleolar ORIF group. Both groups had a syndesmotic fixation percentage change about twice that seen in the isolated lateral malleolus group.

There are several explanations for these trends. First, bimalleolar and trimalleolar fractures are more severe ankle fractures that tend to result from a more forceful mechanism, allowing for a higher rate of syndesmotic injury. Second, these trends likely do not reflect a true increase in the rate of syndesmosis injury but, rather, increased recognition of syndesmotic injury. Third, the data likely reflect a well-established approach to ankle fracture fixation and an increase in thinking that syndesmotic injuries should be stabilized in the setting of ankle fixation.

Incidence of syndesmotic injury as indicated by stabilization procedures can be compared with the data of Vosseller and colleagues,⁸ who reported an incidence of 6445 syndesmotic injuries per year in the United States. Our data showed fewer syndesmotic injuries, which may be related to use of CPT codes rather than ICD-9 codes for database searches, such that only operative syndesmotic injuries are represented in our data. Population differences between the 2 studies could also account for some of the differences in syndesmotic injury incidence.

We also found a significant change in the rate of hardware removal after syndesmosis ORIF. Across all treatment groups, incidence of screw removal decreased—a trend likely reflecting a change in attitude about the need for routine screw removal. Studies have shown that patients have favorable outcomes in the setting of syndesmotic screw loosening and screw breakage.³⁷ Some authors have suggested that screw breakage or removal could be advantageous, as it allows the syndesmosis to settle into a more anatomical position after imperfect reduction.³⁸ In addition, the trend of decreased syndesmotic screw removal could also have resulted from increased suture button fixation, which may less frequently require implant removal. Regardless, the overall trend is that routine syndesmotic implant removal has become less common.

This study had several limitations. First are the many limitations inherent to all studies that use large administrative databases, such as PearlDiver. The power of analysis depends on data quality; potential sources of error include accuracy of billing codes and physicians’ miscoding or noncoding. Although we tried to accurately represent a large population of interest through use of this database, we cannot be sure that the database represents a true cross-section of the United States. In addition, as we could not determine the method of syndesmotic fixation—the same CPT code is used for both suture button fixation and screw fixation—we could not establish trends for the rate of each method. More research is needed to establish these trends, and this research likely will require analysis of data from a large trauma center or from multiple centers.

Potential regional differences are another limitation. In the PearlDiver database, the South and Midwest are highly represented, the Northeast and West much less so. The South, Midwest, and West (but not the Northeast) had similar overall incidence and subgroup incidence of ankle ORIF. However, any regional differences in the rate of syndesmotic fixation could have skewed our data.

Ankle fractures and associated syndesmotic injuries remain a common problem. Although the prevalence of ankle fracture fixation has been relatively constant, the rate of syndesmosis stabilization has increased significantly. Young adults have the highest incidence of ankle fracture and associated syndesmotic fixation, but more ankle fractures occur in the large and growing elderly population. Increased awareness of syndesmotic injury likely has contributed to the recent rise in syndesmosis fixation seen in the present study. Given this trend, we recommend further analysis of outcome data and to establish treatment guidelines.

Am J Orthop. 2016;45(7):E472-E477. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Acute ankle injuries are common problems treated by orthopedic surgeons. In the United States, nearly 2 million ankle sprains occur each year,¹ and ankle fractures account for 9% to 18% of all fractures treated in emergency departments.^2,3 Ankle injuries that involve the syndesmotic ligaments may result in instability and require specific treatment beyond fixation of the malleolar fractures.

The usual mechanism of syndesmotic injury is external rotation of the ankle with hyperdorsiflexion of a pronated or supinated foot.^4,5 Syndesmotic injuries are estimated to occur in up to 10% of ankle sprains⁶ and up to 23% of all ankle fractures.⁷ Overall US incidence of syndesmotic injury is estimated at 6445 injuries per year.⁸ Syndesmotic injury occurs in 39% to 45% of supination-external rotation IV ankle fractures.^9,10 Pronation-external rotation ankle fractures have the highest rate of syndesmotic injury. Syndesmotic injury may be less common in other types of malleolar fracture, but the exact incidence has not been reliably reported.

Traditionally, isolated nondisplaced syndesmotic injuries are treated nonoperatively, and syndesmotic injuries with concomitant malleolar fractures are treated surgically. Various options are available for syndesmotic fixation. The gold standard is syndesmotic screw placement from the lateral aspect of the fibula through the tibia. Fixation may be achieved with screws in a variety of configurations and formats. However, fixation with two 4.5-mm screws is stronger.^11,12 Functional outcomes are similar, regardless of screw material,^13-16 number of cortices,¹⁷ or number of screws.¹⁸ Disadvantages specific to screw fixation include altered ankle biomechanics,^19,20 potential for screw breakage,²¹ and need for implant removal.³Alternatively, suture button fixation is said to be equally as effective as screw fixation in achieving syndesmotic reduction, and their functional outcomes are similar.^22,23 The initial cost of suture button fixation is higher than that of screw fixation, but the difference may be offset by potential elimination of a second surgery for syndesmotic screw removal.²⁴ Soft-tissue irritation caused by the suture material and local osteolysis are reported complications of suture button fixation.^25-27

Regardless of fixation method used, achieving anatomical reduction of the syndesmosis is considered the most important factor in optimizing functional outcomes.^28-31 However, achieving and verifying anatomical reduction of the syndesmosis during surgery can be quite challenging.^30,32-34 Various methods of lowering the malreduction risk, including direct visualization of the tibiofibular joint during reduction^30,35 and intraoperative 3-dimensional imaging,^33,36 have been proposed.

In the study reported here, we used a US insurance database to determine the incidence and rate of syndesmotic stabilization within various ankle injuries and fracture patterns.

Materials and Methods

All data for this study were obtained from a publicly available for-fee healthcare database, the PearlDiver Patient Records Database, which includes procedural volumes and demographic information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the study were derived from 2 databases within PearlDiver: a private-payer database, which has its largest contribution (>30 million individual patient records for 2007-2011) from United HealthCare, and a Medicare database (>50 million patient records for 2007-2011). Access to the database was granted by PearlDiver Technologies for the purpose of academic research. The database was stored on a password-protected server maintained by PearlDiver.

We searched the database for cases of ankle fracture fixation, including fixation of isolated lateral malleolus (CPT 27792), bimalleolar (CPT 27814), and trimalleolar (CPTs 27822 and 27823) fractures. CPT 27829 was used to search for syndesmotic fixation, and CPT 20680 for implant removal. These codes were used individually and in combination.

Overall procedural volume data are reported as number of patients with the given CPT(s) in the database output and as incidence, calculated as number of patients with the CPT of interest normalized to total number of patients in the database for that particular subgroup. Results of age group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who had the CPT procedure of interest that year. As United HealthCare is the largest contributor to the private-payer portion of the database and is represented most prominently in the southern region, data for the regional analysis are presented only as incidence. This incidence was calculated as number of patients in a particular region and year normalized to total number of patients in the database for that region or year. The regions were Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MI, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-square linear-by-linear association analysis was used to determine the statistical significance of time trends in procedural volume, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

 

Results

Number of open reduction and internal fixation (ORIF) procedures increased for all ankle fracture types over the period 2007 to 2011 (Table 1).

Over the same period, number of procedures for isolated syndesmosis ORIF increased significantly (P = .045), by 18%, and the rate of syndesmotic fixation with ORIF of ankle fracture significantly increased for all ankle fracture types (Ps < .0001 for ORIF of lateral malleolus, bimalleolar, and trimalleolar fractures) (Figure).

The largest percentage change (43%) was in the rate of syndesmotic fixation with ORIF of a bimalleolar ankle fracture. The rate of implant removal after syndesmotic fixation significantly decreased for all types of ankle fracture, including those that required only syndesmotic fixation. The largest percentage decrease (32.8%) in implant removal was in the rate of ORIF of a lateral malleolus fracture with syndesmotic fixation (P = .002).

ORIF was performed for an ankle injury in 54,767 patients during the period 2007 to 2011, resulting in a cumulative incidence of 64.2 per 1000 patients (Table 2).

Total number of ankle ORIF procedures increased with each decade of life until age 80 years. Incidence of ankle ORIF was highest for patients 20 years old to 29 years old (151.6/1000 patients). Incidence notably decreased in patients 60 years old to 69 years old (69.1/1000 patients) compared with patients 50 years old to 59 years old (149.5/1000 patients). Lateral malleolus fractures were the most common ankle fractures for every age group until the 50 to 59 year decade, at which point bimalleolar fractures became most common. In all age groups, trimalleolar fractures were the least common ankle fractures.

More ankle ORIF procedures were performed in females (33,565) than in males (21,202); incidence of ankle ORIF procedures was higher in females (68.6/1000 patients) than in males (58.4/1000 patients) (Table 2); percentages of bimalleolar and trimalleolar fractures were higher in females (bi, 40.6%; tri, 27.8%) than in males (bi, 34.6%; tri, 15.2%); and percentage of lateral malleolus fractures was higher in males (50.2%) than in females (31.6%).

Incidence of ankle ORIF procedures was similar in the South (69.6/1000 patients), Midwest (69.4/100 patients), and West (65.1/1000 patients) but lower in the Northeast (43.3/1000 patients) (Table 2). Lateral malleolus fractures were the most common ankle fractures in the Midwest (40.7%) and West (41.3%), followed by bimalleolar fractures (Midwest, 36.3%; West 36.0%) and trimalleolar fractures (Midwest, 23.0%; West, 22.7%). Bimalleolar fractures were most common in the Northeast (40.2%) and South (39.8%), followed by lateral malleolus fractures (Northeast, 34.4%; South, 38.0%) and trimalleolar fractures (Northeast, 25.4%; South, 22.3%).

Discussion

The present study found no significant change in number of lateral malleolus, bimalleolar, and trimalleolar ankle fracture ORIF procedures performed over the period 2007 to 2011. However, over the same period, incidence of syndesmosis fixation increased significantly in patients with isolated syndesmotic injuries and in patients with concomitant ankle fracture and syndesmotic injury. The largest percentage change was found in the bimalleolar ORIF group, which showed nearly a doubling of syndesmotic fixation over the 4-year study period, followed by a 38.1% increase in syndesmotic fixation in the trimalleolar ORIF group. Both groups had a syndesmotic fixation percentage change about twice that seen in the isolated lateral malleolus group.

There are several explanations for these trends. First, bimalleolar and trimalleolar fractures are more severe ankle fractures that tend to result from a more forceful mechanism, allowing for a higher rate of syndesmotic injury. Second, these trends likely do not reflect a true increase in the rate of syndesmosis injury but, rather, increased recognition of syndesmotic injury. Third, the data likely reflect a well-established approach to ankle fracture fixation and an increase in thinking that syndesmotic injuries should be stabilized in the setting of ankle fixation.

Incidence of syndesmotic injury as indicated by stabilization procedures can be compared with the data of Vosseller and colleagues,⁸ who reported an incidence of 6445 syndesmotic injuries per year in the United States. Our data showed fewer syndesmotic injuries, which may be related to use of CPT codes rather than ICD-9 codes for database searches, such that only operative syndesmotic injuries are represented in our data. Population differences between the 2 studies could also account for some of the differences in syndesmotic injury incidence.

We also found a significant change in the rate of hardware removal after syndesmosis ORIF. Across all treatment groups, incidence of screw removal decreased—a trend likely reflecting a change in attitude about the need for routine screw removal. Studies have shown that patients have favorable outcomes in the setting of syndesmotic screw loosening and screw breakage.³⁷ Some authors have suggested that screw breakage or removal could be advantageous, as it allows the syndesmosis to settle into a more anatomical position after imperfect reduction.³⁸ In addition, the trend of decreased syndesmotic screw removal could also have resulted from increased suture button fixation, which may less frequently require implant removal. Regardless, the overall trend is that routine syndesmotic implant removal has become less common.

This study had several limitations. First are the many limitations inherent to all studies that use large administrative databases, such as PearlDiver. The power of analysis depends on data quality; potential sources of error include accuracy of billing codes and physicians’ miscoding or noncoding. Although we tried to accurately represent a large population of interest through use of this database, we cannot be sure that the database represents a true cross-section of the United States. In addition, as we could not determine the method of syndesmotic fixation—the same CPT code is used for both suture button fixation and screw fixation—we could not establish trends for the rate of each method. More research is needed to establish these trends, and this research likely will require analysis of data from a large trauma center or from multiple centers.

Potential regional differences are another limitation. In the PearlDiver database, the South and Midwest are highly represented, the Northeast and West much less so. The South, Midwest, and West (but not the Northeast) had similar overall incidence and subgroup incidence of ankle ORIF. However, any regional differences in the rate of syndesmotic fixation could have skewed our data.

Ankle fractures and associated syndesmotic injuries remain a common problem. Although the prevalence of ankle fracture fixation has been relatively constant, the rate of syndesmosis stabilization has increased significantly. Young adults have the highest incidence of ankle fracture and associated syndesmotic fixation, but more ankle fractures occur in the large and growing elderly population. Increased awareness of syndesmotic injury likely has contributed to the recent rise in syndesmosis fixation seen in the present study. Given this trend, we recommend further analysis of outcome data and to establish treatment guidelines.

Am J Orthop. 2016;45(7):E472-E477. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Acute ankle injuries are common problems treated by orthopedic surgeons. In the United States, nearly 2 million ankle sprains occur each year,¹ and ankle fractures account for 9% to 18% of all fractures treated in emergency departments.^2,3 Ankle injuries that involve the syndesmotic ligaments may result in instability and require specific treatment beyond fixation of the malleolar fractures.

The usual mechanism of syndesmotic injury is external rotation of the ankle with hyperdorsiflexion of a pronated or supinated foot.^4,5 Syndesmotic injuries are estimated to occur in up to 10% of ankle sprains⁶ and up to 23% of all ankle fractures.⁷ Overall US incidence of syndesmotic injury is estimated at 6445 injuries per year.⁸ Syndesmotic injury occurs in 39% to 45% of supination-external rotation IV ankle fractures.^9,10 Pronation-external rotation ankle fractures have the highest rate of syndesmotic injury. Syndesmotic injury may be less common in other types of malleolar fracture, but the exact incidence has not been reliably reported.

Traditionally, isolated nondisplaced syndesmotic injuries are treated nonoperatively, and syndesmotic injuries with concomitant malleolar fractures are treated surgically. Various options are available for syndesmotic fixation. The gold standard is syndesmotic screw placement from the lateral aspect of the fibula through the tibia. Fixation may be achieved with screws in a variety of configurations and formats. However, fixation with two 4.5-mm screws is stronger.^11,12 Functional outcomes are similar, regardless of screw material,^13-16 number of cortices,¹⁷ or number of screws.¹⁸ Disadvantages specific to screw fixation include altered ankle biomechanics,^19,20 potential for screw breakage,²¹ and need for implant removal.³Alternatively, suture button fixation is said to be equally as effective as screw fixation in achieving syndesmotic reduction, and their functional outcomes are similar.^22,23 The initial cost of suture button fixation is higher than that of screw fixation, but the difference may be offset by potential elimination of a second surgery for syndesmotic screw removal.²⁴ Soft-tissue irritation caused by the suture material and local osteolysis are reported complications of suture button fixation.^25-27

Regardless of fixation method used, achieving anatomical reduction of the syndesmosis is considered the most important factor in optimizing functional outcomes.^28-31 However, achieving and verifying anatomical reduction of the syndesmosis during surgery can be quite challenging.^30,32-34 Various methods of lowering the malreduction risk, including direct visualization of the tibiofibular joint during reduction^30,35 and intraoperative 3-dimensional imaging,^33,36 have been proposed.

In the study reported here, we used a US insurance database to determine the incidence and rate of syndesmotic stabilization within various ankle injuries and fracture patterns.

Materials and Methods

All data for this study were obtained from a publicly available for-fee healthcare database, the PearlDiver Patient Records Database, which includes procedural volumes and demographic information for patients with International Classification of Diseases, Ninth Revision (ICD-9) diagnoses and procedures or Current Procedural Terminology (CPT) codes. Data for the study were derived from 2 databases within PearlDiver: a private-payer database, which has its largest contribution (>30 million individual patient records for 2007-2011) from United HealthCare, and a Medicare database (>50 million patient records for 2007-2011). Access to the database was granted by PearlDiver Technologies for the purpose of academic research. The database was stored on a password-protected server maintained by PearlDiver.

We searched the database for cases of ankle fracture fixation, including fixation of isolated lateral malleolus (CPT 27792), bimalleolar (CPT 27814), and trimalleolar (CPTs 27822 and 27823) fractures. CPT 27829 was used to search for syndesmotic fixation, and CPT 20680 for implant removal. These codes were used individually and in combination.

Overall procedural volume data are reported as number of patients with the given CPT(s) in the database output and as incidence, calculated as number of patients with the CPT of interest normalized to total number of patients in the database for that particular subgroup. Results of age group and sex analyses are reported as number of patients reported in the database output and as percentage of patients who had the CPT procedure of interest that year. As United HealthCare is the largest contributor to the private-payer portion of the database and is represented most prominently in the southern region, data for the regional analysis are presented only as incidence. This incidence was calculated as number of patients in a particular region and year normalized to total number of patients in the database for that region or year. The regions were Midwest (IA, IL, IN, KS, MI, MN, MO, ND, NE, OH, SD, WI), Northeast (CT, MA, ME, NH, NJ, NY, PA, RI, VT), South (AL, AR, DC, DE, FL, GA, KY, LA, MD, MI, NC, OK, SC, TN, TX, VA, WV), and West (AK, AZ, CA, CO, HI, ID, MT, NM, NV, OR, UT, WA, WY).

Chi-square linear-by-linear association analysis was used to determine the statistical significance of time trends in procedural volume, sex, age group, and region. For all statistical comparisons, P < .05 was considered significant.

 

Results

Number of open reduction and internal fixation (ORIF) procedures increased for all ankle fracture types over the period 2007 to 2011 (Table 1).

Over the same period, number of procedures for isolated syndesmosis ORIF increased significantly (P = .045), by 18%, and the rate of syndesmotic fixation with ORIF of ankle fracture significantly increased for all ankle fracture types (Ps < .0001 for ORIF of lateral malleolus, bimalleolar, and trimalleolar fractures) (Figure).

The largest percentage change (43%) was in the rate of syndesmotic fixation with ORIF of a bimalleolar ankle fracture. The rate of implant removal after syndesmotic fixation significantly decreased for all types of ankle fracture, including those that required only syndesmotic fixation. The largest percentage decrease (32.8%) in implant removal was in the rate of ORIF of a lateral malleolus fracture with syndesmotic fixation (P = .002).

ORIF was performed for an ankle injury in 54,767 patients during the period 2007 to 2011, resulting in a cumulative incidence of 64.2 per 1000 patients (Table 2).

Total number of ankle ORIF procedures increased with each decade of life until age 80 years. Incidence of ankle ORIF was highest for patients 20 years old to 29 years old (151.6/1000 patients). Incidence notably decreased in patients 60 years old to 69 years old (69.1/1000 patients) compared with patients 50 years old to 59 years old (149.5/1000 patients). Lateral malleolus fractures were the most common ankle fractures for every age group until the 50 to 59 year decade, at which point bimalleolar fractures became most common. In all age groups, trimalleolar fractures were the least common ankle fractures.

More ankle ORIF procedures were performed in females (33,565) than in males (21,202); incidence of ankle ORIF procedures was higher in females (68.6/1000 patients) than in males (58.4/1000 patients) (Table 2); percentages of bimalleolar and trimalleolar fractures were higher in females (bi, 40.6%; tri, 27.8%) than in males (bi, 34.6%; tri, 15.2%); and percentage of lateral malleolus fractures was higher in males (50.2%) than in females (31.6%).

Incidence of ankle ORIF procedures was similar in the South (69.6/1000 patients), Midwest (69.4/100 patients), and West (65.1/1000 patients) but lower in the Northeast (43.3/1000 patients) (Table 2). Lateral malleolus fractures were the most common ankle fractures in the Midwest (40.7%) and West (41.3%), followed by bimalleolar fractures (Midwest, 36.3%; West 36.0%) and trimalleolar fractures (Midwest, 23.0%; West, 22.7%). Bimalleolar fractures were most common in the Northeast (40.2%) and South (39.8%), followed by lateral malleolus fractures (Northeast, 34.4%; South, 38.0%) and trimalleolar fractures (Northeast, 25.4%; South, 22.3%).

Discussion

The present study found no significant change in number of lateral malleolus, bimalleolar, and trimalleolar ankle fracture ORIF procedures performed over the period 2007 to 2011. However, over the same period, incidence of syndesmosis fixation increased significantly in patients with isolated syndesmotic injuries and in patients with concomitant ankle fracture and syndesmotic injury. The largest percentage change was found in the bimalleolar ORIF group, which showed nearly a doubling of syndesmotic fixation over the 4-year study period, followed by a 38.1% increase in syndesmotic fixation in the trimalleolar ORIF group. Both groups had a syndesmotic fixation percentage change about twice that seen in the isolated lateral malleolus group.

There are several explanations for these trends. First, bimalleolar and trimalleolar fractures are more severe ankle fractures that tend to result from a more forceful mechanism, allowing for a higher rate of syndesmotic injury. Second, these trends likely do not reflect a true increase in the rate of syndesmosis injury but, rather, increased recognition of syndesmotic injury. Third, the data likely reflect a well-established approach to ankle fracture fixation and an increase in thinking that syndesmotic injuries should be stabilized in the setting of ankle fixation.

Incidence of syndesmotic injury as indicated by stabilization procedures can be compared with the data of Vosseller and colleagues,⁸ who reported an incidence of 6445 syndesmotic injuries per year in the United States. Our data showed fewer syndesmotic injuries, which may be related to use of CPT codes rather than ICD-9 codes for database searches, such that only operative syndesmotic injuries are represented in our data. Population differences between the 2 studies could also account for some of the differences in syndesmotic injury incidence.

We also found a significant change in the rate of hardware removal after syndesmosis ORIF. Across all treatment groups, incidence of screw removal decreased—a trend likely reflecting a change in attitude about the need for routine screw removal. Studies have shown that patients have favorable outcomes in the setting of syndesmotic screw loosening and screw breakage.³⁷ Some authors have suggested that screw breakage or removal could be advantageous, as it allows the syndesmosis to settle into a more anatomical position after imperfect reduction.³⁸ In addition, the trend of decreased syndesmotic screw removal could also have resulted from increased suture button fixation, which may less frequently require implant removal. Regardless, the overall trend is that routine syndesmotic implant removal has become less common.

This study had several limitations. First are the many limitations inherent to all studies that use large administrative databases, such as PearlDiver. The power of analysis depends on data quality; potential sources of error include accuracy of billing codes and physicians’ miscoding or noncoding. Although we tried to accurately represent a large population of interest through use of this database, we cannot be sure that the database represents a true cross-section of the United States. In addition, as we could not determine the method of syndesmotic fixation—the same CPT code is used for both suture button fixation and screw fixation—we could not establish trends for the rate of each method. More research is needed to establish these trends, and this research likely will require analysis of data from a large trauma center or from multiple centers.

Potential regional differences are another limitation. In the PearlDiver database, the South and Midwest are highly represented, the Northeast and West much less so. The South, Midwest, and West (but not the Northeast) had similar overall incidence and subgroup incidence of ankle ORIF. However, any regional differences in the rate of syndesmotic fixation could have skewed our data.

Ankle fractures and associated syndesmotic injuries remain a common problem. Although the prevalence of ankle fracture fixation has been relatively constant, the rate of syndesmosis stabilization has increased significantly. Young adults have the highest incidence of ankle fracture and associated syndesmotic fixation, but more ankle fractures occur in the large and growing elderly population. Increased awareness of syndesmotic injury likely has contributed to the recent rise in syndesmosis fixation seen in the present study. Given this trend, we recommend further analysis of outcome data and to establish treatment guidelines.

Am J Orthop. 2016;45(7):E472-E477. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Pathology of the biceps-labrum complex (BLC) can be an important source of shoulder pain. Discussion of pathoanatomy, imaging, and surgical intervention is facilitated by distinguishing the anatomical zones of the BLC: inside, junction, and bicipital tunnel (extra-articular), parts of which cannot be visualized with standard diagnostic arthroscopy.

The recent literature indicates that bicipital tunnel lesions are common and perhaps overlooked. Systematic reviews suggest improvement in outcomes of BLC operations when the bicipital tunnel is decompressed. Higher-level clinical and basic science studies are needed to fully elucidate the role of the bicipital tunnel, but it is evident that a comprehensive physical examination and an understanding of the limits of advanced imaging are necessary to correctly diagnose and treat BLC-related shoulder pain.

Anatomy of Biceps-Labrum Complex

The long head of the biceps tendon (LHBT) and the glenoid labrum work as an interdependent functional unit, the biceps-labrum complex (BLC). The BLC is divided into 3 distinct anatomical zones: inside, junction, and bicipital tunnel.^1,2

Inside

The inside includes the superior labrum and biceps attachment. The LHBT most commonly originates in the superior labrum.^3-5 Vangsness and colleagues³ described 4 types of LHBT origins: Type I biceps attaches solely to the posterior labrum, type II predominantly posterior, type III equally to the anterior and posterior labrum, and type IV mostly to the anterior labrum. The LHBT can also originate in the supraglenoid tubercle or the inferior border of the supraspinatus.^3,6

Junction

Junction is the intra-articular segment of the LHBT and the biceps pulley. The LHBT traverses the glenohumeral joint en route to the extra-articular bicipital tunnel.² The LHBT is enveloped in synovium that extends into part of the bicipital tunnel.² The intra-articular segment of the LHBT is about 25 mm in length⁷ and has a diameter of 5 mm to 6 mm.⁸

A cadaveric study found that the average length of the LHBT that can be arthroscopically visualized at rest is 35.6 mm, or only 40% of the total length of the LHBT with respect to the proximal margin of the pectoralis major tendon.¹ When the LHBT was pulled into the joint, more tendon (another 14 mm) was visualized.¹ Therefore, diagnostic arthroscopy of the glenohumeral joint visualizes about 50% of the LHBT.⁹The morphology of the LHBT varies by location. The intra-articular portion of the LHBT is wide and flat, whereas the extra-articular portion is round.⁸ The tendon becomes smoother and more avascular as it exits the joint to promote gliding within its sheath in the bicipital groove.¹⁰ The proximal LHBT receives its vascular supply from superior labrum tributaries, and distally the LHBT is supplied by ascending branches of the anterior humeral circumflex artery.⁴ There is a hypovascular zone, created by this dual blood supply, about 12 mm to 30 mm from the LHBT origin, predisposing the tendon to rupture or fray in this region.¹¹The LHBT makes a 30° turn into the biceps pulley system as it exits the glenohumeral joint. The fibrous pulley system that stabilizes the LHBT in this region has contributions from the coracohumeral ligament, the superior glenohumeral ligament, and the supraspinatus tendon.^12-14

The floor of the pulley consists of the superior glenohumeral ligament with reinforcing fibers from the superior border of the subscapularis tendon.¹⁵ The roof consists of the coracohumeral ligament fibers with supraspinatus fibers contributing posteriorly (Figure 1).¹²

Bicipital Tunnel

The bicipital tunnel, the third portion of the BLC, remains largely hidden from standard diagnostic glenohumeral arthroscopy. The bicipital tunnel is an extra-articular, closed space that constrains the LHBT from the articular margin through the subpectoral region.²

The bicipital tunnel itself can be divided into 3 zones (Figure 2).²

Zone 1 is the traditional bicipital groove or “bony groove” that extends from the articular margin to the distal margin of the subscapularis tendon. The floor consists of a deep osseous groove covered by a continuation of subscapularis tendon fibers and periosteum.²Zone 2, “no man’s land,” extends from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major (PMPM). The LHBT in this zone cannot be visualized during a pull test at arthroscopy, yet lesions commonly occur here.¹ Zones 1 and 2 have a similar histology and contain synovium.²Zone 3 is the subpectoral region distal to the PMPM. Fibers of the latissimus dorsi form the flat floor of zone 3, and the pectoralis major inserts lateral to the LHBT on the humerus in this zone. The synovium encapsulating the LHBT in zones 1 and 2 rarely extends past the PMPM. Taylor and colleagues² found a higher percentage of unoccupied tunnel space in zone 3 than in zones 1 and 2, which results in a “functional bottleneck” between zones 2 and 3 represented by the PMPM.

 

Pathoanatomy

BLC lesions may occur in isolation or concomitantly across multiple anatomical zones. In a series of 277 chronically symptomatic shoulders that underwent transfer of the LHBT to the conjoint tendon with subdeltoid arthroscopy, Taylor and colleagues¹ found 47% incidence of bicipital tunnel lesions, 44% incidence of junctional lesions, and 35% incidence of inside lesions. In their series, 37% of patients had concomitant lesions involving more than 1 anatomical zone.

Inside Lesions

Inside lesions involve the superior labrum, the LHBT origin, or both. Superior labrum anterior-posterior (SLAP) tears are included as inside BLC lesions. Snyder and colleagues¹⁶ originally identified 4 broad categories of SLAP tears, but Powell and colleagues¹⁷ described up to 10 variations. Type II lesions, which are the most common, destabilize the biceps anchor.

Dynamic incarceration of the biceps between the humeral head and the glenoid labrum is another inside lesion that can be identified during routine diagnostic glenohumeral arthroscopy. The arthroscopic active compression test, as described by Verma and colleagues,¹⁸ can be used during surgery to demonstrate incarceration of the biceps tendon.

Medial biceps chondromalacia, attritional chondral wear along the anteromedial aspect of the humeral head, occurs secondary to a windshield wiper effect of the LHBT in the setting of an incarcerating LHBT or may be associated with destabilization of the biceps pulley.

Junctional Lesions

Junctional lesions, which include lesions that affect the intra-articular LHBT, can be visualized during routine glenohumeral arthroscopy. They include partial and complete biceps tears, biceps pulley lesions, and junctional biceps chondromalacia.

Biceps pulley injuries and/or tears of the upper subscapularis tendon can destabilize the biceps as it exits the joint, and this destabilization may result in medial subluxation of the tendon and the aforementioned medial biceps chondromalacia.^10,19 Junctional biceps chondromalacia is attritional chondral wear of the humeral head from abnormal tracking of the LHBT deep to the LHBT near the articular margin.

Recently elucidated is the limited ability of diagnostic glenohumeral arthroscopy to fully identify the extent of BLC pathology.^1,20-22 Gilmer and colleagues²⁰ found that diagnostic arthroscopy identified only 67% of biceps pathology and underestimated its extent in 56% of patients in their series. Similarly, Moon and colleagues²¹ found that 79% of proximal LHBT tears propagated distally into the bicipital tunnel and were incompletely visualized with standard arthroscopy.

Bicipital Tunnel Lesions

Recent evidence indicates that the bicipital tunnel is a closed space that often conceals space-occupying lesions, including scar, synovitis, loose bodies, and osteophytes, which can become trapped in the tunnel. The functional bottleneck between zones 2 and 3 of the bicipital tunnel explains the aggregation of loose bodies in this region.² Similarly, as the percentage of free space within the bicipital tunnel increases, space-occupying lesions (eg scar, loose bodies, osteophytes) may exude a compressive and/or abrasive force within zones 1 and 2, but not as commonly within zone 3.²

Physical Examination of Biceps-Labrum Complex

Accurate diagnosis of BLC disease is crucial in selecting an optimal intervention, but challenging. Beyond identifying biceps pathology, specific examination maneuvers may help distinguish between lesions of the intra-articular BLC and lesions of the extra-articular bicipital tunnel.²³

Traditional examination maneuvers for biceps-related shoulder pain include the Speed test, the full can test, and the Yergason test.^24,25 For the Speed test, the patient forward-flexes the shoulder to 60° to 90°, extends the arm at the elbow, and supinates the forearm. The clinician applies a downward force as the patient resists. The reported sensitivity of the Speed test ranges from 37% to 63%, and specificity is 60% to 88%.^25,26 In the full can test, with the patient’s arm in the plane of the scapula, the shoulder abducted to 90°, and the forearm in neutral rotation, a downward force is applied against resistance. Sensitivity of the full can test is 60% to 67%, and specificity is 76% to 84%.²⁴ The Yergason test is performed with the patient’s arm at his or her side, the elbow flexed to 90°, and the forearm pronated. The patient supinates the forearm against the clinician’s resistance. Sensitivity of the Yergason test is 19% to 32%, and specificity is 70% to 100%.^25,26 The Yergason test has a positive predictive value of 92% for bicipital tunnel disease.

O’Brien and colleagues^23,26 introduced a “3-pack” physical examination designed to elicit BLC symptoms. In this examination, the LHBT is palpated along its course within the bicipital tunnel. Reproduction of the patient’s pain by palpation had a sensitivity of 98% for bicipital tunnel disease but was less specific (70%). Gill and colleagues²⁷ reported low sensitivity (53%) and low specificity (54%) for biceps palpation, and they used arthroscopy as a gold standard. Since then, multiple studies have demonstrated that glenohumeral arthroscopy fails to identify lesions concealed within the bicipital tunnel.^20-22The second part of the 3-pack examination is the active compression test. A downward force is applied as the patient resists with his or her arm forward-flexed to 90° and adducted 10° to 15° with the thumb pointing downward.²⁸ This action is repeated with the humerus externally rotated and the forearm supinated. A positive test is indicated by reproduction of symptoms with the thumb down, and elimination or reduction of symptoms with the palm up. Test sensitivity is 88% to 96%, and specificity is 46% to 64% for BLC lesions, but for bicipital tunnel disease sensitivity is higher (96%), and the negative predictive value is 93%.²⁶The third component of the 3-pack examination is the throwing test. A late-cocking throwing position is re-created with the shoulder externally rotated and abducted to 90° and the elbow flexed to 90°. The patient steps forward with the contralateral leg and moves into the acceleration phase of throwing while the clinician provides isometric resistance. If this maneuver reproduces pain, the test is positive. As Taylor and colleagues²⁶ reported, the throwing test has sensitivity of 73% to 77% and specificity of 65% to 79% for BLC pathology. This test has moderate sensitivity and negative predictive value for bicipital tunnel disease but may be the only positive test on physical examination in the setting of LHBT instability.

 

Imaging of Biceps-Labrum Complex

Plain anteroposterior, lateral, and axillary radiographs of the shoulder should be obtained for all patients having an orthopedic examination for shoulder pain. Magnetic resonance imaging (MRI) and ultrasound are the advanced modalities most commonly used for diagnostic imaging. These modalities should be considered in conjunction with, not in place of, a comprehensive history and physical examination.

The literature suggests MRI fails to accurately detect many LHBT lesions (Table).^29-37

MRI has sensitivity of 9% to 89% for LHBT pathology^29-37 and 38% to 98% for SLAP pathology.^35,38-41 The wide range of reported sensitivity and specificity might be attributed to the varying criteria for what constitutes a BLC lesion. Some authors include biceps chondromalacia, dynamic incarceration of LHBT, and extra-articular bicipital tunnel lesions, while others historically have included only intra-articular LHBT lesions that can be directly visualized arthroscopically.

In their retrospective review of 277 shoulders with chronic refractory BLC symptoms treated with subdeltoid transfer of the LHBT to the conjoint tendon, Taylor and colleagues³⁰ reported MRI was more sensitive for inside BLC lesions than for junctional or bicipital tunnel lesions (77% vs 43% and 50%, respectively).

Treatment Options for Biceps-Labrum Complex Lesions

A diagnosis of BLC disease warrants a trial of conservative (nonoperative) management for at least 3 months. Many patients improve with activity modification, use of oral anti-inflammatory medication, and structured physical therapy focused on dynamic stabilizers and range of motion. If pain persists, local anesthetic and corticosteroid can be injected under ultrasound guidance into the bicipital tunnel; this injection has the advantage of being both diagnostic and therapeutic. Hashiuchi and colleagues⁴² found ultrasound-guided injections are 87% successful in achieving intra-sheath placement (injections without ultrasound guidance are only 27% successful).

If the 3-month trial of conservative management fails, surgical intervention should be considered. The goal in treating BLC pain is to maximize clinical function and alleviate pain in a predictable manner while minimizing technical demands and morbidity. A singular solution has not been identified. Furthermore, 3 systematic reviews failed to identify a difference between the most commonly used techniques, biceps tenodesis and tenotomy.^43-45 These reviews grouped all tenotomy procedures together and compared them with all tenodesis procedures. A limitation of these systematic reviews is that they did not differentiate tenodesis techniques. We prefer to classify techniques according to whether or not they decompress zones 1 and 2 of the bicipital tunnel.

Bicipital Tunnel Nondecompressing Techniques

Release of the biceps tendon, a biceps tenotomy, is a simple procedure that potentially avoids open surgery and provides patients with a quick return to activity. Disadvantages of tenotomy include cosmetic (Popeye) deformity after surgery, potential cramping and fatigue, and biomechanical changes in the humeral head,^46-48 particularly among patients younger than 65 years. High rates of revision after tenotomy have been reported.^43,49 Incomplete retraction of the LHBT and/or residual synovium may be responsible for refractory pain following biceps tenotomy.⁴⁹ We hypothesize that failure of tenotomy may be related to unaddressed bicipital tunnel disease.

Proximal nondecompressing tenodesis techniques may be performed either on soft tissue in the interval or rotator cuff or on bone at the articular margin or within zone 1 of the bicipital tunnel.^50-52 These techniques can be performed with standard glenohumeral arthroscopy and generally are fast and well tolerated and have limited operative morbidity. Advantages of these techniques over simple tenotomy are lower rates of cosmetic deformity and lower rates of cramping and fatigue pain, likely resulting from maintenance of the muscle tension relationship of the LHBT. Disadvantages of proximal tenodesis techniques include introduction of hardware for bony fixation, longer postoperative rehabilitation to protect repairs, and failure to address hidden bicipital tunnel disease. Furthermore, the rate of stiffness in patients who undergo proximal tenodesis without decompression of the bicipital tunnel may be as high as 18%.⁵³

Bicipital Tunnel Decompressing Techniques

Surgical techniques that decompress the bicipital tunnel include proximal techniques that release the bicipital sheath within zones 1 and 2 of the bicipital tunnel (to the level of the proximal margin of the pectoralis major tendon) and certain arthroscopic suprapectoral techniques,⁵⁴ open subpectoral tenodeses,^55-57 and arthroscopic transfer of the LHBT to the conjoint tendon.^58,59

Open subpectoral tenodesis techniques have the advantage of maintaining the length-tension relationship of the LHBT and preventing Popeye deformity. However, these techniques require making an incision near the axilla, which may introduce an unnecessary source of infection. Furthermore, open subpectoral tenodesis requires drilling the humerus and placing a screw for bony fixation of the LHBT, which can create a risk of neurovascular injury, given the proximity of neurovascular structures,^60-62 and humeral shaft fracture, particularly in athletes.^63,64Our preferred method is transfer of the LHBT to the conjoint tendon (Figure 3).⁵⁹

The subdeltoid space is a large, relatively avascular fascial plane bounded superiorly by the acromion and coracoacromial ligament, medially by the coracoid and conjoint tendon, inferiorly by the musculotendinous insertion of the pectoralis major, and laterally by the border of the humerus.⁶⁵ After the LHBT is released from the superior labrum, it is transferred to the subdeltoid space and sutured to the conjoint tendon in side-to-side fashion with nonabsorbable sutures.^58,59 This technique allows for isometric tensioning of the LHBT, which preserves the strength of the biceps muscle, and fixation of soft tissue to soft tissue obviates the need for bone tunnels, mitigating fracture risk. A histologic study that compared healing between LHBT tenodesis with bone and soft-tissue transfer to the conjoint tendon found a more robust response of tenomodulin in the soft-tissue transfer, suggesting tendon regeneration in this technique.⁶⁶ Perhaps the most significant advantage is the ability of this approach to effectively decompress the bicipital tunnel. Early-term results were promising, and recent midterm results demonstrated durability of clinical outcomes.^58,59Sanders and colleagues⁴⁹ compared revision rates of biceps procedures and found a 6.8% rate for techniques that released the biceps sheath and a 20.6% rate for operations in which the sheath was not released. Subsequent meta-analysis of 30 studies (1881 patients) found improved Constant scores in the cohort that underwent bicipital tunnel decompression in comparison with the cohort that did not have the bicipital tunnel decompressed, but there was no significant difference in UCLA (University of California Los Angeles) scores between cohorts.67 

In light of recent literature that confirms the prevalence of bicipital tunnel lesions that have been overlooked, and the power of physical examination, we have proposed an evidence-based approach to diagnosing and managing BLC disease (Figure 4).

 

Am J Orthop. 2016;45(7):E503-E511. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Pathology of the biceps-labrum complex (BLC) can be an important source of shoulder pain. Discussion of pathoanatomy, imaging, and surgical intervention is facilitated by distinguishing the anatomical zones of the BLC: inside, junction, and bicipital tunnel (extra-articular), parts of which cannot be visualized with standard diagnostic arthroscopy.

The recent literature indicates that bicipital tunnel lesions are common and perhaps overlooked. Systematic reviews suggest improvement in outcomes of BLC operations when the bicipital tunnel is decompressed. Higher-level clinical and basic science studies are needed to fully elucidate the role of the bicipital tunnel, but it is evident that a comprehensive physical examination and an understanding of the limits of advanced imaging are necessary to correctly diagnose and treat BLC-related shoulder pain.

Anatomy of Biceps-Labrum Complex

The long head of the biceps tendon (LHBT) and the glenoid labrum work as an interdependent functional unit, the biceps-labrum complex (BLC). The BLC is divided into 3 distinct anatomical zones: inside, junction, and bicipital tunnel.^1,2

Inside

The inside includes the superior labrum and biceps attachment. The LHBT most commonly originates in the superior labrum.^3-5 Vangsness and colleagues³ described 4 types of LHBT origins: Type I biceps attaches solely to the posterior labrum, type II predominantly posterior, type III equally to the anterior and posterior labrum, and type IV mostly to the anterior labrum. The LHBT can also originate in the supraglenoid tubercle or the inferior border of the supraspinatus.^3,6

Junction

Junction is the intra-articular segment of the LHBT and the biceps pulley. The LHBT traverses the glenohumeral joint en route to the extra-articular bicipital tunnel.² The LHBT is enveloped in synovium that extends into part of the bicipital tunnel.² The intra-articular segment of the LHBT is about 25 mm in length⁷ and has a diameter of 5 mm to 6 mm.⁸

A cadaveric study found that the average length of the LHBT that can be arthroscopically visualized at rest is 35.6 mm, or only 40% of the total length of the LHBT with respect to the proximal margin of the pectoralis major tendon.¹ When the LHBT was pulled into the joint, more tendon (another 14 mm) was visualized.¹ Therefore, diagnostic arthroscopy of the glenohumeral joint visualizes about 50% of the LHBT.⁹The morphology of the LHBT varies by location. The intra-articular portion of the LHBT is wide and flat, whereas the extra-articular portion is round.⁸ The tendon becomes smoother and more avascular as it exits the joint to promote gliding within its sheath in the bicipital groove.¹⁰ The proximal LHBT receives its vascular supply from superior labrum tributaries, and distally the LHBT is supplied by ascending branches of the anterior humeral circumflex artery.⁴ There is a hypovascular zone, created by this dual blood supply, about 12 mm to 30 mm from the LHBT origin, predisposing the tendon to rupture or fray in this region.¹¹The LHBT makes a 30° turn into the biceps pulley system as it exits the glenohumeral joint. The fibrous pulley system that stabilizes the LHBT in this region has contributions from the coracohumeral ligament, the superior glenohumeral ligament, and the supraspinatus tendon.^12-14

The floor of the pulley consists of the superior glenohumeral ligament with reinforcing fibers from the superior border of the subscapularis tendon.¹⁵ The roof consists of the coracohumeral ligament fibers with supraspinatus fibers contributing posteriorly (Figure 1).¹²

Bicipital Tunnel

The bicipital tunnel, the third portion of the BLC, remains largely hidden from standard diagnostic glenohumeral arthroscopy. The bicipital tunnel is an extra-articular, closed space that constrains the LHBT from the articular margin through the subpectoral region.²

The bicipital tunnel itself can be divided into 3 zones (Figure 2).²

Zone 1 is the traditional bicipital groove or “bony groove” that extends from the articular margin to the distal margin of the subscapularis tendon. The floor consists of a deep osseous groove covered by a continuation of subscapularis tendon fibers and periosteum.²Zone 2, “no man’s land,” extends from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major (PMPM). The LHBT in this zone cannot be visualized during a pull test at arthroscopy, yet lesions commonly occur here.¹ Zones 1 and 2 have a similar histology and contain synovium.²Zone 3 is the subpectoral region distal to the PMPM. Fibers of the latissimus dorsi form the flat floor of zone 3, and the pectoralis major inserts lateral to the LHBT on the humerus in this zone. The synovium encapsulating the LHBT in zones 1 and 2 rarely extends past the PMPM. Taylor and colleagues² found a higher percentage of unoccupied tunnel space in zone 3 than in zones 1 and 2, which results in a “functional bottleneck” between zones 2 and 3 represented by the PMPM.

 

Pathoanatomy

BLC lesions may occur in isolation or concomitantly across multiple anatomical zones. In a series of 277 chronically symptomatic shoulders that underwent transfer of the LHBT to the conjoint tendon with subdeltoid arthroscopy, Taylor and colleagues¹ found 47% incidence of bicipital tunnel lesions, 44% incidence of junctional lesions, and 35% incidence of inside lesions. In their series, 37% of patients had concomitant lesions involving more than 1 anatomical zone.

Inside Lesions

Inside lesions involve the superior labrum, the LHBT origin, or both. Superior labrum anterior-posterior (SLAP) tears are included as inside BLC lesions. Snyder and colleagues¹⁶ originally identified 4 broad categories of SLAP tears, but Powell and colleagues¹⁷ described up to 10 variations. Type II lesions, which are the most common, destabilize the biceps anchor.

Dynamic incarceration of the biceps between the humeral head and the glenoid labrum is another inside lesion that can be identified during routine diagnostic glenohumeral arthroscopy. The arthroscopic active compression test, as described by Verma and colleagues,¹⁸ can be used during surgery to demonstrate incarceration of the biceps tendon.

Medial biceps chondromalacia, attritional chondral wear along the anteromedial aspect of the humeral head, occurs secondary to a windshield wiper effect of the LHBT in the setting of an incarcerating LHBT or may be associated with destabilization of the biceps pulley.

Junctional Lesions

Junctional lesions, which include lesions that affect the intra-articular LHBT, can be visualized during routine glenohumeral arthroscopy. They include partial and complete biceps tears, biceps pulley lesions, and junctional biceps chondromalacia.

Biceps pulley injuries and/or tears of the upper subscapularis tendon can destabilize the biceps as it exits the joint, and this destabilization may result in medial subluxation of the tendon and the aforementioned medial biceps chondromalacia.^10,19 Junctional biceps chondromalacia is attritional chondral wear of the humeral head from abnormal tracking of the LHBT deep to the LHBT near the articular margin.

Recently elucidated is the limited ability of diagnostic glenohumeral arthroscopy to fully identify the extent of BLC pathology.^1,20-22 Gilmer and colleagues²⁰ found that diagnostic arthroscopy identified only 67% of biceps pathology and underestimated its extent in 56% of patients in their series. Similarly, Moon and colleagues²¹ found that 79% of proximal LHBT tears propagated distally into the bicipital tunnel and were incompletely visualized with standard arthroscopy.

Bicipital Tunnel Lesions

Recent evidence indicates that the bicipital tunnel is a closed space that often conceals space-occupying lesions, including scar, synovitis, loose bodies, and osteophytes, which can become trapped in the tunnel. The functional bottleneck between zones 2 and 3 of the bicipital tunnel explains the aggregation of loose bodies in this region.² Similarly, as the percentage of free space within the bicipital tunnel increases, space-occupying lesions (eg scar, loose bodies, osteophytes) may exude a compressive and/or abrasive force within zones 1 and 2, but not as commonly within zone 3.²

Physical Examination of Biceps-Labrum Complex

Accurate diagnosis of BLC disease is crucial in selecting an optimal intervention, but challenging. Beyond identifying biceps pathology, specific examination maneuvers may help distinguish between lesions of the intra-articular BLC and lesions of the extra-articular bicipital tunnel.²³

Traditional examination maneuvers for biceps-related shoulder pain include the Speed test, the full can test, and the Yergason test.^24,25 For the Speed test, the patient forward-flexes the shoulder to 60° to 90°, extends the arm at the elbow, and supinates the forearm. The clinician applies a downward force as the patient resists. The reported sensitivity of the Speed test ranges from 37% to 63%, and specificity is 60% to 88%.^25,26 In the full can test, with the patient’s arm in the plane of the scapula, the shoulder abducted to 90°, and the forearm in neutral rotation, a downward force is applied against resistance. Sensitivity of the full can test is 60% to 67%, and specificity is 76% to 84%.²⁴ The Yergason test is performed with the patient’s arm at his or her side, the elbow flexed to 90°, and the forearm pronated. The patient supinates the forearm against the clinician’s resistance. Sensitivity of the Yergason test is 19% to 32%, and specificity is 70% to 100%.^25,26 The Yergason test has a positive predictive value of 92% for bicipital tunnel disease.

O’Brien and colleagues^23,26 introduced a “3-pack” physical examination designed to elicit BLC symptoms. In this examination, the LHBT is palpated along its course within the bicipital tunnel. Reproduction of the patient’s pain by palpation had a sensitivity of 98% for bicipital tunnel disease but was less specific (70%). Gill and colleagues²⁷ reported low sensitivity (53%) and low specificity (54%) for biceps palpation, and they used arthroscopy as a gold standard. Since then, multiple studies have demonstrated that glenohumeral arthroscopy fails to identify lesions concealed within the bicipital tunnel.^20-22The second part of the 3-pack examination is the active compression test. A downward force is applied as the patient resists with his or her arm forward-flexed to 90° and adducted 10° to 15° with the thumb pointing downward.²⁸ This action is repeated with the humerus externally rotated and the forearm supinated. A positive test is indicated by reproduction of symptoms with the thumb down, and elimination or reduction of symptoms with the palm up. Test sensitivity is 88% to 96%, and specificity is 46% to 64% for BLC lesions, but for bicipital tunnel disease sensitivity is higher (96%), and the negative predictive value is 93%.²⁶The third component of the 3-pack examination is the throwing test. A late-cocking throwing position is re-created with the shoulder externally rotated and abducted to 90° and the elbow flexed to 90°. The patient steps forward with the contralateral leg and moves into the acceleration phase of throwing while the clinician provides isometric resistance. If this maneuver reproduces pain, the test is positive. As Taylor and colleagues²⁶ reported, the throwing test has sensitivity of 73% to 77% and specificity of 65% to 79% for BLC pathology. This test has moderate sensitivity and negative predictive value for bicipital tunnel disease but may be the only positive test on physical examination in the setting of LHBT instability.

 

Imaging of Biceps-Labrum Complex

Plain anteroposterior, lateral, and axillary radiographs of the shoulder should be obtained for all patients having an orthopedic examination for shoulder pain. Magnetic resonance imaging (MRI) and ultrasound are the advanced modalities most commonly used for diagnostic imaging. These modalities should be considered in conjunction with, not in place of, a comprehensive history and physical examination.

The literature suggests MRI fails to accurately detect many LHBT lesions (Table).^29-37

MRI has sensitivity of 9% to 89% for LHBT pathology^29-37 and 38% to 98% for SLAP pathology.^35,38-41 The wide range of reported sensitivity and specificity might be attributed to the varying criteria for what constitutes a BLC lesion. Some authors include biceps chondromalacia, dynamic incarceration of LHBT, and extra-articular bicipital tunnel lesions, while others historically have included only intra-articular LHBT lesions that can be directly visualized arthroscopically.

In their retrospective review of 277 shoulders with chronic refractory BLC symptoms treated with subdeltoid transfer of the LHBT to the conjoint tendon, Taylor and colleagues³⁰ reported MRI was more sensitive for inside BLC lesions than for junctional or bicipital tunnel lesions (77% vs 43% and 50%, respectively).

Treatment Options for Biceps-Labrum Complex Lesions

A diagnosis of BLC disease warrants a trial of conservative (nonoperative) management for at least 3 months. Many patients improve with activity modification, use of oral anti-inflammatory medication, and structured physical therapy focused on dynamic stabilizers and range of motion. If pain persists, local anesthetic and corticosteroid can be injected under ultrasound guidance into the bicipital tunnel; this injection has the advantage of being both diagnostic and therapeutic. Hashiuchi and colleagues⁴² found ultrasound-guided injections are 87% successful in achieving intra-sheath placement (injections without ultrasound guidance are only 27% successful).

If the 3-month trial of conservative management fails, surgical intervention should be considered. The goal in treating BLC pain is to maximize clinical function and alleviate pain in a predictable manner while minimizing technical demands and morbidity. A singular solution has not been identified. Furthermore, 3 systematic reviews failed to identify a difference between the most commonly used techniques, biceps tenodesis and tenotomy.^43-45 These reviews grouped all tenotomy procedures together and compared them with all tenodesis procedures. A limitation of these systematic reviews is that they did not differentiate tenodesis techniques. We prefer to classify techniques according to whether or not they decompress zones 1 and 2 of the bicipital tunnel.

Bicipital Tunnel Nondecompressing Techniques

Release of the biceps tendon, a biceps tenotomy, is a simple procedure that potentially avoids open surgery and provides patients with a quick return to activity. Disadvantages of tenotomy include cosmetic (Popeye) deformity after surgery, potential cramping and fatigue, and biomechanical changes in the humeral head,^46-48 particularly among patients younger than 65 years. High rates of revision after tenotomy have been reported.^43,49 Incomplete retraction of the LHBT and/or residual synovium may be responsible for refractory pain following biceps tenotomy.⁴⁹ We hypothesize that failure of tenotomy may be related to unaddressed bicipital tunnel disease.

Proximal nondecompressing tenodesis techniques may be performed either on soft tissue in the interval or rotator cuff or on bone at the articular margin or within zone 1 of the bicipital tunnel.^50-52 These techniques can be performed with standard glenohumeral arthroscopy and generally are fast and well tolerated and have limited operative morbidity. Advantages of these techniques over simple tenotomy are lower rates of cosmetic deformity and lower rates of cramping and fatigue pain, likely resulting from maintenance of the muscle tension relationship of the LHBT. Disadvantages of proximal tenodesis techniques include introduction of hardware for bony fixation, longer postoperative rehabilitation to protect repairs, and failure to address hidden bicipital tunnel disease. Furthermore, the rate of stiffness in patients who undergo proximal tenodesis without decompression of the bicipital tunnel may be as high as 18%.⁵³

Bicipital Tunnel Decompressing Techniques

Surgical techniques that decompress the bicipital tunnel include proximal techniques that release the bicipital sheath within zones 1 and 2 of the bicipital tunnel (to the level of the proximal margin of the pectoralis major tendon) and certain arthroscopic suprapectoral techniques,⁵⁴ open subpectoral tenodeses,^55-57 and arthroscopic transfer of the LHBT to the conjoint tendon.^58,59

Open subpectoral tenodesis techniques have the advantage of maintaining the length-tension relationship of the LHBT and preventing Popeye deformity. However, these techniques require making an incision near the axilla, which may introduce an unnecessary source of infection. Furthermore, open subpectoral tenodesis requires drilling the humerus and placing a screw for bony fixation of the LHBT, which can create a risk of neurovascular injury, given the proximity of neurovascular structures,^60-62 and humeral shaft fracture, particularly in athletes.^63,64Our preferred method is transfer of the LHBT to the conjoint tendon (Figure 3).⁵⁹

The subdeltoid space is a large, relatively avascular fascial plane bounded superiorly by the acromion and coracoacromial ligament, medially by the coracoid and conjoint tendon, inferiorly by the musculotendinous insertion of the pectoralis major, and laterally by the border of the humerus.⁶⁵ After the LHBT is released from the superior labrum, it is transferred to the subdeltoid space and sutured to the conjoint tendon in side-to-side fashion with nonabsorbable sutures.^58,59 This technique allows for isometric tensioning of the LHBT, which preserves the strength of the biceps muscle, and fixation of soft tissue to soft tissue obviates the need for bone tunnels, mitigating fracture risk. A histologic study that compared healing between LHBT tenodesis with bone and soft-tissue transfer to the conjoint tendon found a more robust response of tenomodulin in the soft-tissue transfer, suggesting tendon regeneration in this technique.⁶⁶ Perhaps the most significant advantage is the ability of this approach to effectively decompress the bicipital tunnel. Early-term results were promising, and recent midterm results demonstrated durability of clinical outcomes.^58,59Sanders and colleagues⁴⁹ compared revision rates of biceps procedures and found a 6.8% rate for techniques that released the biceps sheath and a 20.6% rate for operations in which the sheath was not released. Subsequent meta-analysis of 30 studies (1881 patients) found improved Constant scores in the cohort that underwent bicipital tunnel decompression in comparison with the cohort that did not have the bicipital tunnel decompressed, but there was no significant difference in UCLA (University of California Los Angeles) scores between cohorts.67 

In light of recent literature that confirms the prevalence of bicipital tunnel lesions that have been overlooked, and the power of physical examination, we have proposed an evidence-based approach to diagnosing and managing BLC disease (Figure 4).

 

Am J Orthop. 2016;45(7):E503-E511. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Pathology of the biceps-labrum complex (BLC) can be an important source of shoulder pain. Discussion of pathoanatomy, imaging, and surgical intervention is facilitated by distinguishing the anatomical zones of the BLC: inside, junction, and bicipital tunnel (extra-articular), parts of which cannot be visualized with standard diagnostic arthroscopy.

The recent literature indicates that bicipital tunnel lesions are common and perhaps overlooked. Systematic reviews suggest improvement in outcomes of BLC operations when the bicipital tunnel is decompressed. Higher-level clinical and basic science studies are needed to fully elucidate the role of the bicipital tunnel, but it is evident that a comprehensive physical examination and an understanding of the limits of advanced imaging are necessary to correctly diagnose and treat BLC-related shoulder pain.

Anatomy of Biceps-Labrum Complex

The long head of the biceps tendon (LHBT) and the glenoid labrum work as an interdependent functional unit, the biceps-labrum complex (BLC). The BLC is divided into 3 distinct anatomical zones: inside, junction, and bicipital tunnel.^1,2

Inside

The inside includes the superior labrum and biceps attachment. The LHBT most commonly originates in the superior labrum.^3-5 Vangsness and colleagues³ described 4 types of LHBT origins: Type I biceps attaches solely to the posterior labrum, type II predominantly posterior, type III equally to the anterior and posterior labrum, and type IV mostly to the anterior labrum. The LHBT can also originate in the supraglenoid tubercle or the inferior border of the supraspinatus.^3,6

Junction

Junction is the intra-articular segment of the LHBT and the biceps pulley. The LHBT traverses the glenohumeral joint en route to the extra-articular bicipital tunnel.² The LHBT is enveloped in synovium that extends into part of the bicipital tunnel.² The intra-articular segment of the LHBT is about 25 mm in length⁷ and has a diameter of 5 mm to 6 mm.⁸

A cadaveric study found that the average length of the LHBT that can be arthroscopically visualized at rest is 35.6 mm, or only 40% of the total length of the LHBT with respect to the proximal margin of the pectoralis major tendon.¹ When the LHBT was pulled into the joint, more tendon (another 14 mm) was visualized.¹ Therefore, diagnostic arthroscopy of the glenohumeral joint visualizes about 50% of the LHBT.⁹The morphology of the LHBT varies by location. The intra-articular portion of the LHBT is wide and flat, whereas the extra-articular portion is round.⁸ The tendon becomes smoother and more avascular as it exits the joint to promote gliding within its sheath in the bicipital groove.¹⁰ The proximal LHBT receives its vascular supply from superior labrum tributaries, and distally the LHBT is supplied by ascending branches of the anterior humeral circumflex artery.⁴ There is a hypovascular zone, created by this dual blood supply, about 12 mm to 30 mm from the LHBT origin, predisposing the tendon to rupture or fray in this region.¹¹The LHBT makes a 30° turn into the biceps pulley system as it exits the glenohumeral joint. The fibrous pulley system that stabilizes the LHBT in this region has contributions from the coracohumeral ligament, the superior glenohumeral ligament, and the supraspinatus tendon.^12-14

The floor of the pulley consists of the superior glenohumeral ligament with reinforcing fibers from the superior border of the subscapularis tendon.¹⁵ The roof consists of the coracohumeral ligament fibers with supraspinatus fibers contributing posteriorly (Figure 1).¹²

Bicipital Tunnel

The bicipital tunnel, the third portion of the BLC, remains largely hidden from standard diagnostic glenohumeral arthroscopy. The bicipital tunnel is an extra-articular, closed space that constrains the LHBT from the articular margin through the subpectoral region.²

The bicipital tunnel itself can be divided into 3 zones (Figure 2).²

Zone 1 is the traditional bicipital groove or “bony groove” that extends from the articular margin to the distal margin of the subscapularis tendon. The floor consists of a deep osseous groove covered by a continuation of subscapularis tendon fibers and periosteum.²Zone 2, “no man’s land,” extends from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major (PMPM). The LHBT in this zone cannot be visualized during a pull test at arthroscopy, yet lesions commonly occur here.¹ Zones 1 and 2 have a similar histology and contain synovium.²Zone 3 is the subpectoral region distal to the PMPM. Fibers of the latissimus dorsi form the flat floor of zone 3, and the pectoralis major inserts lateral to the LHBT on the humerus in this zone. The synovium encapsulating the LHBT in zones 1 and 2 rarely extends past the PMPM. Taylor and colleagues² found a higher percentage of unoccupied tunnel space in zone 3 than in zones 1 and 2, which results in a “functional bottleneck” between zones 2 and 3 represented by the PMPM.

 

Pathoanatomy

BLC lesions may occur in isolation or concomitantly across multiple anatomical zones. In a series of 277 chronically symptomatic shoulders that underwent transfer of the LHBT to the conjoint tendon with subdeltoid arthroscopy, Taylor and colleagues¹ found 47% incidence of bicipital tunnel lesions, 44% incidence of junctional lesions, and 35% incidence of inside lesions. In their series, 37% of patients had concomitant lesions involving more than 1 anatomical zone.

Inside Lesions

Inside lesions involve the superior labrum, the LHBT origin, or both. Superior labrum anterior-posterior (SLAP) tears are included as inside BLC lesions. Snyder and colleagues¹⁶ originally identified 4 broad categories of SLAP tears, but Powell and colleagues¹⁷ described up to 10 variations. Type II lesions, which are the most common, destabilize the biceps anchor.

Dynamic incarceration of the biceps between the humeral head and the glenoid labrum is another inside lesion that can be identified during routine diagnostic glenohumeral arthroscopy. The arthroscopic active compression test, as described by Verma and colleagues,¹⁸ can be used during surgery to demonstrate incarceration of the biceps tendon.

Medial biceps chondromalacia, attritional chondral wear along the anteromedial aspect of the humeral head, occurs secondary to a windshield wiper effect of the LHBT in the setting of an incarcerating LHBT or may be associated with destabilization of the biceps pulley.

Junctional Lesions

Junctional lesions, which include lesions that affect the intra-articular LHBT, can be visualized during routine glenohumeral arthroscopy. They include partial and complete biceps tears, biceps pulley lesions, and junctional biceps chondromalacia.

Biceps pulley injuries and/or tears of the upper subscapularis tendon can destabilize the biceps as it exits the joint, and this destabilization may result in medial subluxation of the tendon and the aforementioned medial biceps chondromalacia.^10,19 Junctional biceps chondromalacia is attritional chondral wear of the humeral head from abnormal tracking of the LHBT deep to the LHBT near the articular margin.

Recently elucidated is the limited ability of diagnostic glenohumeral arthroscopy to fully identify the extent of BLC pathology.^1,20-22 Gilmer and colleagues²⁰ found that diagnostic arthroscopy identified only 67% of biceps pathology and underestimated its extent in 56% of patients in their series. Similarly, Moon and colleagues²¹ found that 79% of proximal LHBT tears propagated distally into the bicipital tunnel and were incompletely visualized with standard arthroscopy.

Bicipital Tunnel Lesions

Recent evidence indicates that the bicipital tunnel is a closed space that often conceals space-occupying lesions, including scar, synovitis, loose bodies, and osteophytes, which can become trapped in the tunnel. The functional bottleneck between zones 2 and 3 of the bicipital tunnel explains the aggregation of loose bodies in this region.² Similarly, as the percentage of free space within the bicipital tunnel increases, space-occupying lesions (eg scar, loose bodies, osteophytes) may exude a compressive and/or abrasive force within zones 1 and 2, but not as commonly within zone 3.²

Physical Examination of Biceps-Labrum Complex

Accurate diagnosis of BLC disease is crucial in selecting an optimal intervention, but challenging. Beyond identifying biceps pathology, specific examination maneuvers may help distinguish between lesions of the intra-articular BLC and lesions of the extra-articular bicipital tunnel.²³

Traditional examination maneuvers for biceps-related shoulder pain include the Speed test, the full can test, and the Yergason test.^24,25 For the Speed test, the patient forward-flexes the shoulder to 60° to 90°, extends the arm at the elbow, and supinates the forearm. The clinician applies a downward force as the patient resists. The reported sensitivity of the Speed test ranges from 37% to 63%, and specificity is 60% to 88%.^25,26 In the full can test, with the patient’s arm in the plane of the scapula, the shoulder abducted to 90°, and the forearm in neutral rotation, a downward force is applied against resistance. Sensitivity of the full can test is 60% to 67%, and specificity is 76% to 84%.²⁴ The Yergason test is performed with the patient’s arm at his or her side, the elbow flexed to 90°, and the forearm pronated. The patient supinates the forearm against the clinician’s resistance. Sensitivity of the Yergason test is 19% to 32%, and specificity is 70% to 100%.^25,26 The Yergason test has a positive predictive value of 92% for bicipital tunnel disease.

O’Brien and colleagues^23,26 introduced a “3-pack” physical examination designed to elicit BLC symptoms. In this examination, the LHBT is palpated along its course within the bicipital tunnel. Reproduction of the patient’s pain by palpation had a sensitivity of 98% for bicipital tunnel disease but was less specific (70%). Gill and colleagues²⁷ reported low sensitivity (53%) and low specificity (54%) for biceps palpation, and they used arthroscopy as a gold standard. Since then, multiple studies have demonstrated that glenohumeral arthroscopy fails to identify lesions concealed within the bicipital tunnel.^20-22The second part of the 3-pack examination is the active compression test. A downward force is applied as the patient resists with his or her arm forward-flexed to 90° and adducted 10° to 15° with the thumb pointing downward.²⁸ This action is repeated with the humerus externally rotated and the forearm supinated. A positive test is indicated by reproduction of symptoms with the thumb down, and elimination or reduction of symptoms with the palm up. Test sensitivity is 88% to 96%, and specificity is 46% to 64% for BLC lesions, but for bicipital tunnel disease sensitivity is higher (96%), and the negative predictive value is 93%.²⁶The third component of the 3-pack examination is the throwing test. A late-cocking throwing position is re-created with the shoulder externally rotated and abducted to 90° and the elbow flexed to 90°. The patient steps forward with the contralateral leg and moves into the acceleration phase of throwing while the clinician provides isometric resistance. If this maneuver reproduces pain, the test is positive. As Taylor and colleagues²⁶ reported, the throwing test has sensitivity of 73% to 77% and specificity of 65% to 79% for BLC pathology. This test has moderate sensitivity and negative predictive value for bicipital tunnel disease but may be the only positive test on physical examination in the setting of LHBT instability.

 

Imaging of Biceps-Labrum Complex

Plain anteroposterior, lateral, and axillary radiographs of the shoulder should be obtained for all patients having an orthopedic examination for shoulder pain. Magnetic resonance imaging (MRI) and ultrasound are the advanced modalities most commonly used for diagnostic imaging. These modalities should be considered in conjunction with, not in place of, a comprehensive history and physical examination.

The literature suggests MRI fails to accurately detect many LHBT lesions (Table).^29-37

MRI has sensitivity of 9% to 89% for LHBT pathology^29-37 and 38% to 98% for SLAP pathology.^35,38-41 The wide range of reported sensitivity and specificity might be attributed to the varying criteria for what constitutes a BLC lesion. Some authors include biceps chondromalacia, dynamic incarceration of LHBT, and extra-articular bicipital tunnel lesions, while others historically have included only intra-articular LHBT lesions that can be directly visualized arthroscopically.

In their retrospective review of 277 shoulders with chronic refractory BLC symptoms treated with subdeltoid transfer of the LHBT to the conjoint tendon, Taylor and colleagues³⁰ reported MRI was more sensitive for inside BLC lesions than for junctional or bicipital tunnel lesions (77% vs 43% and 50%, respectively).

Treatment Options for Biceps-Labrum Complex Lesions

A diagnosis of BLC disease warrants a trial of conservative (nonoperative) management for at least 3 months. Many patients improve with activity modification, use of oral anti-inflammatory medication, and structured physical therapy focused on dynamic stabilizers and range of motion. If pain persists, local anesthetic and corticosteroid can be injected under ultrasound guidance into the bicipital tunnel; this injection has the advantage of being both diagnostic and therapeutic. Hashiuchi and colleagues⁴² found ultrasound-guided injections are 87% successful in achieving intra-sheath placement (injections without ultrasound guidance are only 27% successful).

If the 3-month trial of conservative management fails, surgical intervention should be considered. The goal in treating BLC pain is to maximize clinical function and alleviate pain in a predictable manner while minimizing technical demands and morbidity. A singular solution has not been identified. Furthermore, 3 systematic reviews failed to identify a difference between the most commonly used techniques, biceps tenodesis and tenotomy.^43-45 These reviews grouped all tenotomy procedures together and compared them with all tenodesis procedures. A limitation of these systematic reviews is that they did not differentiate tenodesis techniques. We prefer to classify techniques according to whether or not they decompress zones 1 and 2 of the bicipital tunnel.

Bicipital Tunnel Nondecompressing Techniques

Release of the biceps tendon, a biceps tenotomy, is a simple procedure that potentially avoids open surgery and provides patients with a quick return to activity. Disadvantages of tenotomy include cosmetic (Popeye) deformity after surgery, potential cramping and fatigue, and biomechanical changes in the humeral head,^46-48 particularly among patients younger than 65 years. High rates of revision after tenotomy have been reported.^43,49 Incomplete retraction of the LHBT and/or residual synovium may be responsible for refractory pain following biceps tenotomy.⁴⁹ We hypothesize that failure of tenotomy may be related to unaddressed bicipital tunnel disease.

Proximal nondecompressing tenodesis techniques may be performed either on soft tissue in the interval or rotator cuff or on bone at the articular margin or within zone 1 of the bicipital tunnel.^50-52 These techniques can be performed with standard glenohumeral arthroscopy and generally are fast and well tolerated and have limited operative morbidity. Advantages of these techniques over simple tenotomy are lower rates of cosmetic deformity and lower rates of cramping and fatigue pain, likely resulting from maintenance of the muscle tension relationship of the LHBT. Disadvantages of proximal tenodesis techniques include introduction of hardware for bony fixation, longer postoperative rehabilitation to protect repairs, and failure to address hidden bicipital tunnel disease. Furthermore, the rate of stiffness in patients who undergo proximal tenodesis without decompression of the bicipital tunnel may be as high as 18%.⁵³

Bicipital Tunnel Decompressing Techniques

Surgical techniques that decompress the bicipital tunnel include proximal techniques that release the bicipital sheath within zones 1 and 2 of the bicipital tunnel (to the level of the proximal margin of the pectoralis major tendon) and certain arthroscopic suprapectoral techniques,⁵⁴ open subpectoral tenodeses,^55-57 and arthroscopic transfer of the LHBT to the conjoint tendon.^58,59

Open subpectoral tenodesis techniques have the advantage of maintaining the length-tension relationship of the LHBT and preventing Popeye deformity. However, these techniques require making an incision near the axilla, which may introduce an unnecessary source of infection. Furthermore, open subpectoral tenodesis requires drilling the humerus and placing a screw for bony fixation of the LHBT, which can create a risk of neurovascular injury, given the proximity of neurovascular structures,^60-62 and humeral shaft fracture, particularly in athletes.^63,64Our preferred method is transfer of the LHBT to the conjoint tendon (Figure 3).⁵⁹

The subdeltoid space is a large, relatively avascular fascial plane bounded superiorly by the acromion and coracoacromial ligament, medially by the coracoid and conjoint tendon, inferiorly by the musculotendinous insertion of the pectoralis major, and laterally by the border of the humerus.⁶⁵ After the LHBT is released from the superior labrum, it is transferred to the subdeltoid space and sutured to the conjoint tendon in side-to-side fashion with nonabsorbable sutures.^58,59 This technique allows for isometric tensioning of the LHBT, which preserves the strength of the biceps muscle, and fixation of soft tissue to soft tissue obviates the need for bone tunnels, mitigating fracture risk. A histologic study that compared healing between LHBT tenodesis with bone and soft-tissue transfer to the conjoint tendon found a more robust response of tenomodulin in the soft-tissue transfer, suggesting tendon regeneration in this technique.⁶⁶ Perhaps the most significant advantage is the ability of this approach to effectively decompress the bicipital tunnel. Early-term results were promising, and recent midterm results demonstrated durability of clinical outcomes.^58,59Sanders and colleagues⁴⁹ compared revision rates of biceps procedures and found a 6.8% rate for techniques that released the biceps sheath and a 20.6% rate for operations in which the sheath was not released. Subsequent meta-analysis of 30 studies (1881 patients) found improved Constant scores in the cohort that underwent bicipital tunnel decompression in comparison with the cohort that did not have the bicipital tunnel decompressed, but there was no significant difference in UCLA (University of California Los Angeles) scores between cohorts.67 

In light of recent literature that confirms the prevalence of bicipital tunnel lesions that have been overlooked, and the power of physical examination, we have proposed an evidence-based approach to diagnosing and managing BLC disease (Figure 4).

 

Am J Orthop. 2016;45(7):E503-E511. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Dislocation of the knee is a severe injury that usually results from high-energy blunt trauma.¹ Recognition of knee dislocations has increased with expansion of the definition beyond radiographically confirmed loss of tibiofemoral articulation to include injury of multiple knee ligaments with multidirectional joint instability, or the rupture of the anterior and posterior cruciate ligaments (ACL, PCL) when no gross dislocation can be identified² (though knee dislocations without rupture of either ligament have been reported^3,4). Knee dislocations account for 0.02% to 0.2% of orthopedic injuries.⁵ These multiligamentous injuries are rare, but their clinical outcomes are often complicated by arthrofibrosis, pain, and instability, as surgeons contend with the competing interests of long-term joint stability and range of motion (ROM).^6-9

Whereas treatment standards for acute knee dislocations are becoming clearer, treatment of subacute and chronic tibiofemoral dislocations and subluxations is less defined.⁵ Success with articulated external fixation originally across the ankle and elbow inspired interest in its use for the knee.^10-12 Richter and Lobenhoffer¹³ and Simonian and colleagues¹⁴ were the first to report on the postoperative use of a hinged external fixation device to help maintain the reduction of chronic fixed posterior knee dislocations. The literature has even supported nonoperative reduction of small fixed anterior or posterior (sagittal) subluxations with knee bracing alone.^15,16 However, there are no reports on treatment of chronic tibial subluxation in the coronal plane.

We report a case of a hinged-knee external fixator (HEF) used alone to reduce a chronic medial tibia subluxation that presented after initial repair of a knee dislocation sustained in a motor vehicle accident. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 51-year-old healthy woman who was traveling out of state sustained multiple orthopedic injuries in a motor vehicle accident. She had a pelvic fracture, a contralateral femoral shaft fracture, significant multiligamentous damage to the right knee, and a cavitary impaction fracture of the tibial eminence with resultant coronal tibial subluxation. Initial magnetic resonance imaging (MRI) showed the tibia injury likely was the result of varus translation, as the medial femoral condyle impacted the tibial spine, disrupting the ACL (Figures 1A, 1B).

The patient also had disruption of the posterolateral corner (PLC), including a lateral collateral ligament (LCL) fibular avulsion, an iliotibial band avulsion, and a popliteus myotendinous junction tear with an intact biceps femoris tendon. Three weeks after the accident and after the associated polytrauma injuries were stabilized, the patient underwent “en masse” repair of the PLC, at an outside institution, as described by Shelbourne and colleagues¹⁷ with tibial spine and ACL débridement.

On initial presentation to our clinic 5 weeks after injury, x-rays showed progressive medial subluxation of the tibia in relation to the femur with translation of about a third of the tibial width medially (Figures 2A, 2B).

The central tibial defect nearly apposed the medial femoral condyle, consistent with the initial impaction injury with translation in the coronal rather than anteroposterior plane. Additional MRI and computed tomography were performed to better define the bony and ligamentous anatomy (Figures 3A-3C).

They showed an intact en masse lateral repair, an intact superficial medial collateral ligament, a bucket-handle lateral meniscus tear, and absence of the ACL and tibial eminence.

Given the worsening tibial subluxation and resultant instability, the patient was taken to the operating room for examination under anesthesia, and planned closed reduction and spanning external fixation. Fluoroscopy of the lateral translation and external rotation of the tibia allowed us to reduce the joint, with the lateral tibial plateau and lateral femoral condyle relatively but not completely concentric. A rigid spanning multiplanar external fixator was then placed to maintain the knee joint in a more reduced position.

A week later, the patient was taken back to the operating room for arthroscopic evaluation of the knee joint. At the time of her index operation at the outside institution, she had undergone arthroscopic débridement of intra-articular loose bodies and lateral meniscus repair. Now it was found that the meniscus was not healed but had displaced. A bucket-handle lateral meniscus tear appeared to be blocking lateral translation of the tibia, thus impeding complete reduction.

Given the meniscus deformity that resulted from the chronicity of the injury and the resultant subluxation, a sub-total lateral meniscectomy was performed. As the patient was now noted to have an intact medial collateral ligament and an intact en masse lateral repair, we converted the spanning external fixator to a Compass Universal Hinge (Smith & Nephew) to maintain reduction without further ligamentous reconstruction (Figure 4).

As we were able to maintain reduction, we thought bone grafting for stability augmentation was not needed, despite the central tibial defect (analogous to an engaging Hill-Sachs defect in shoulder instability). The HEF allowed knee flexion while maintaining coronal alignment.

After HEF placement, the patient spent a short time recovering at an inpatient rehabilitation facility before starting aggressive twice-a-week outpatient physical therapy. Initially after HEF placement, she could not actively flex the knee to about 40° or fully extend it concentrically. Given these limitations and concern about interval development of arthrofibrosis, manipulation under anesthesia was performed, 3 weeks after surgery, and 90° of flexion was obtained.

When the HEF was removed, 6 weeks after placement, fluoroscopy and radiographs showed maintained tibiofemoral alignment (Figures 5A, 5B).

Six weeks after HEF removal, the patient was ambulating well with a cane, pain was minimal, and knee ROM was up to 110° of flexion. Tibiofemoral stability remained constant—no change in medial or lateral joint space opening. Full-extension radiographs showed medial translation of about 5 mm, which decreased to 1 mm on Rosenberg view. This represents marked improvement over the severe subluxation on initial presentation.

Follow-up over the next months revealed continued improvement in the right lower extremity strength, increased tolerance for physical activity, and stable right medial tibial translation.

A year after HEF removal, imaging showed adequate tibiofemoral alignment (Figures 6A-6C). There was mild to moderate joint space narrowing, lateral more than medial.

At 5-year follow-up, the patient was asymptomatic, had continued coronal and sagittal stability, and was tolerating regular aerobic exercise, including hiking, weight training, and cycling. Physical examination revealed grade 1B Lachman, grade 0 pivot shift, and grade 0 posterior drawer. There was 3 mm increased lateral compartment opening in full extension, which increased to about 6 mm at 30° with endpoint.

Radiographs (Figures 7A-7C) showed stable 2-mm coronal translation and asymptomatic though severe lateral compartment arthritis, likely secondary to the multiligament knee injury and the sub–total lateral meniscectomy performed on top of previous lateral compartment arthritis. Final International Knee Documentation Committee (IKDC) score was 78.2, final Tegner Lysholm Knee Score was 94 (“excellent”), Modified Cincinnati Rating System score was 80 (“excellent”), and Knee Injury and Osteoarthritis Outcome Score was 87.5.

 

Discussion

Although knee dislocations with multiligamentous involvement are rare, their outcomes can be poor. Fortunately, the principles of managing these complex injuries in the acute stage are becoming clearer. In a systematic review, Levy and colleagues¹⁸ found that operative treatment of a dislocated knee within 3 weeks after injury, compared with nonoperative or delayed treatment, resulted in improved functional outcomes. Ligament repair and reconstruction yielded similar outcomes, though repair of the posterolateral corner had a comparatively higher rate of failure. For associated lateral injuries, Shelbourne and colleagues¹⁷ advocated en masse repair in which the healing tissue complex is reattached to the tibia nonanatomically, without dissecting individual structures—a technique used in the original repair of our patient’s injuries.

Originally designed for other joints, hinged external fixators are now occasionally used for rehabilitation after traumatic knee injury. Stannard and colleagues⁹ recently confirmed the utility of the HEF as a supplement to ligament reconstruction for recovery from acute knee dislocation.⁹ Compared with postoperative use of a hinged-knee brace, HEF use resulted in fewer failed ligament reconstructions as well as equivalent joint ROM and Lysholm and IKDC scores at final follow-up. This clinical outcome is supported by results of kinematic studies of these hinged devices, which are capable of rigid fixation in all planes except sagittal and can reduce stress on intra-articular and periarticular ligaments when placed on the appropriate flexion-extension axis of the knee.^19,20Unfortunately, the situation is more complicated for subacute or chronic tibial subluxation than for acute subluxation. Maak and colleagues¹⁶ described 3 operative steps that are crucial in obtaining desired outcomes in this setting: complete release of scar tissue, re-creation of knee axis through ACL and PCL reconstruction, and postoperative application of a HEF or knee brace. These recommendations mimic the management course described by Richter and Lobenhoffer¹³ and Simonian and colleagues,¹⁴ who treated chronic fixed posterior tibial subluxations with arthrolysis, ligament reconstruction, and use of HEFs for 6 weeks, supporting postoperative rehabilitation. All cases maintained reduction at follow-up after fixator removal.

It is also possible for small fixed anterior or posterior tibial subluxations to be managed nonoperatively. Strobel and colleagues¹⁵ described a series of 109 patients with fixed posterior subluxations treated at night with posterior tibial support braces. Mean subluxation was reduced from 6.93 mm to 2.58 mm after an average treatment period of 180 days. Although 60% of all subluxations were completely reduced, reductions were significantly more successful for those displaced <10 mm.

Management of subacute or chronic fixed coronal tibial subluxations is yet to be described. In this article, we have reported on acceptable reduction of a subacute medial tibial subluxation with use of a HEF for 6 weeks after arthroscopic débridement of a deformed subacute bucket-handle lateral meniscus tear. Our case report is unique in that it describes use of a HEF alone for the reduction of a subacute tibial subluxation in any plane without the need for more extensive ligament reconstruction.

The injury here was primarily a lateral ligamentous injury. In the nonanatomical repair that was performed, the LCL and the iliotibial band were reattached to the proximal-lateral tibia. Had we started treating this injury from the time of the patient’s accident, then, depending on repair integrity, we might have considered acute augmentation of the anatomical repair of LCL with Larson-type reconstruction of the LCL and the popliteofibular ligament. Alternatively, acute reconstruction of the LCL and popliteus would be considered if the lateral structures were either irreparable or of very poor quality. In addition, had we initially seen the coronal instability/translation, we might have acutely considered either a staged procedure of a multiplanar external fixator or a HEF.

Given the narrowed lateral joint space, the débridement of the lateral meniscus, and the risk of developing posttraumatic arthritis, our patient will probably need total knee arthroplasty (TKA) at some point. We informed her that she had advanced lateral compartment joint space narrowing and arthritic progression and that she would eventually need TKA based on pain or dysfunction. We think the longevity of that TKA will be predictable and good, as she now had improved tibiofemoral alignment and stability of the collateral ligamentous structures. If she had been allowed to maintain the coronally subluxed position, it would have led to medial ligamentous attenuation and would have compromised the success and longevity of the TKA. In essence, a crucial part of the utility of the HEF was improved coronal tibiofemoral alignment and, therefore, decreased abnormal forces on both the repaired lateral ligaments and the native medial ligamentous structures. Although temporary external fixation issues related to infection risk and patient discomfort are recognized,^21-23 use of HEF alone can be part of the treatment considerations for fixed tibial subluxations in any plane when they present after treatment for multiligamentous injury.

Am J Orthop. 2016;45(7):E497-E502. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Dislocation of the knee is a severe injury that usually results from high-energy blunt trauma.¹ Recognition of knee dislocations has increased with expansion of the definition beyond radiographically confirmed loss of tibiofemoral articulation to include injury of multiple knee ligaments with multidirectional joint instability, or the rupture of the anterior and posterior cruciate ligaments (ACL, PCL) when no gross dislocation can be identified² (though knee dislocations without rupture of either ligament have been reported^3,4). Knee dislocations account for 0.02% to 0.2% of orthopedic injuries.⁵ These multiligamentous injuries are rare, but their clinical outcomes are often complicated by arthrofibrosis, pain, and instability, as surgeons contend with the competing interests of long-term joint stability and range of motion (ROM).^6-9

Whereas treatment standards for acute knee dislocations are becoming clearer, treatment of subacute and chronic tibiofemoral dislocations and subluxations is less defined.⁵ Success with articulated external fixation originally across the ankle and elbow inspired interest in its use for the knee.^10-12 Richter and Lobenhoffer¹³ and Simonian and colleagues¹⁴ were the first to report on the postoperative use of a hinged external fixation device to help maintain the reduction of chronic fixed posterior knee dislocations. The literature has even supported nonoperative reduction of small fixed anterior or posterior (sagittal) subluxations with knee bracing alone.^15,16 However, there are no reports on treatment of chronic tibial subluxation in the coronal plane.

We report a case of a hinged-knee external fixator (HEF) used alone to reduce a chronic medial tibia subluxation that presented after initial repair of a knee dislocation sustained in a motor vehicle accident. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 51-year-old healthy woman who was traveling out of state sustained multiple orthopedic injuries in a motor vehicle accident. She had a pelvic fracture, a contralateral femoral shaft fracture, significant multiligamentous damage to the right knee, and a cavitary impaction fracture of the tibial eminence with resultant coronal tibial subluxation. Initial magnetic resonance imaging (MRI) showed the tibia injury likely was the result of varus translation, as the medial femoral condyle impacted the tibial spine, disrupting the ACL (Figures 1A, 1B).

The patient also had disruption of the posterolateral corner (PLC), including a lateral collateral ligament (LCL) fibular avulsion, an iliotibial band avulsion, and a popliteus myotendinous junction tear with an intact biceps femoris tendon. Three weeks after the accident and after the associated polytrauma injuries were stabilized, the patient underwent “en masse” repair of the PLC, at an outside institution, as described by Shelbourne and colleagues¹⁷ with tibial spine and ACL débridement.

On initial presentation to our clinic 5 weeks after injury, x-rays showed progressive medial subluxation of the tibia in relation to the femur with translation of about a third of the tibial width medially (Figures 2A, 2B).

The central tibial defect nearly apposed the medial femoral condyle, consistent with the initial impaction injury with translation in the coronal rather than anteroposterior plane. Additional MRI and computed tomography were performed to better define the bony and ligamentous anatomy (Figures 3A-3C).

They showed an intact en masse lateral repair, an intact superficial medial collateral ligament, a bucket-handle lateral meniscus tear, and absence of the ACL and tibial eminence.

Given the worsening tibial subluxation and resultant instability, the patient was taken to the operating room for examination under anesthesia, and planned closed reduction and spanning external fixation. Fluoroscopy of the lateral translation and external rotation of the tibia allowed us to reduce the joint, with the lateral tibial plateau and lateral femoral condyle relatively but not completely concentric. A rigid spanning multiplanar external fixator was then placed to maintain the knee joint in a more reduced position.

A week later, the patient was taken back to the operating room for arthroscopic evaluation of the knee joint. At the time of her index operation at the outside institution, she had undergone arthroscopic débridement of intra-articular loose bodies and lateral meniscus repair. Now it was found that the meniscus was not healed but had displaced. A bucket-handle lateral meniscus tear appeared to be blocking lateral translation of the tibia, thus impeding complete reduction.

Given the meniscus deformity that resulted from the chronicity of the injury and the resultant subluxation, a sub-total lateral meniscectomy was performed. As the patient was now noted to have an intact medial collateral ligament and an intact en masse lateral repair, we converted the spanning external fixator to a Compass Universal Hinge (Smith & Nephew) to maintain reduction without further ligamentous reconstruction (Figure 4).

As we were able to maintain reduction, we thought bone grafting for stability augmentation was not needed, despite the central tibial defect (analogous to an engaging Hill-Sachs defect in shoulder instability). The HEF allowed knee flexion while maintaining coronal alignment.

After HEF placement, the patient spent a short time recovering at an inpatient rehabilitation facility before starting aggressive twice-a-week outpatient physical therapy. Initially after HEF placement, she could not actively flex the knee to about 40° or fully extend it concentrically. Given these limitations and concern about interval development of arthrofibrosis, manipulation under anesthesia was performed, 3 weeks after surgery, and 90° of flexion was obtained.

When the HEF was removed, 6 weeks after placement, fluoroscopy and radiographs showed maintained tibiofemoral alignment (Figures 5A, 5B).

Six weeks after HEF removal, the patient was ambulating well with a cane, pain was minimal, and knee ROM was up to 110° of flexion. Tibiofemoral stability remained constant—no change in medial or lateral joint space opening. Full-extension radiographs showed medial translation of about 5 mm, which decreased to 1 mm on Rosenberg view. This represents marked improvement over the severe subluxation on initial presentation.

Follow-up over the next months revealed continued improvement in the right lower extremity strength, increased tolerance for physical activity, and stable right medial tibial translation.

A year after HEF removal, imaging showed adequate tibiofemoral alignment (Figures 6A-6C). There was mild to moderate joint space narrowing, lateral more than medial.

At 5-year follow-up, the patient was asymptomatic, had continued coronal and sagittal stability, and was tolerating regular aerobic exercise, including hiking, weight training, and cycling. Physical examination revealed grade 1B Lachman, grade 0 pivot shift, and grade 0 posterior drawer. There was 3 mm increased lateral compartment opening in full extension, which increased to about 6 mm at 30° with endpoint.

Radiographs (Figures 7A-7C) showed stable 2-mm coronal translation and asymptomatic though severe lateral compartment arthritis, likely secondary to the multiligament knee injury and the sub–total lateral meniscectomy performed on top of previous lateral compartment arthritis. Final International Knee Documentation Committee (IKDC) score was 78.2, final Tegner Lysholm Knee Score was 94 (“excellent”), Modified Cincinnati Rating System score was 80 (“excellent”), and Knee Injury and Osteoarthritis Outcome Score was 87.5.

 

Discussion

Although knee dislocations with multiligamentous involvement are rare, their outcomes can be poor. Fortunately, the principles of managing these complex injuries in the acute stage are becoming clearer. In a systematic review, Levy and colleagues¹⁸ found that operative treatment of a dislocated knee within 3 weeks after injury, compared with nonoperative or delayed treatment, resulted in improved functional outcomes. Ligament repair and reconstruction yielded similar outcomes, though repair of the posterolateral corner had a comparatively higher rate of failure. For associated lateral injuries, Shelbourne and colleagues¹⁷ advocated en masse repair in which the healing tissue complex is reattached to the tibia nonanatomically, without dissecting individual structures—a technique used in the original repair of our patient’s injuries.

Originally designed for other joints, hinged external fixators are now occasionally used for rehabilitation after traumatic knee injury. Stannard and colleagues⁹ recently confirmed the utility of the HEF as a supplement to ligament reconstruction for recovery from acute knee dislocation.⁹ Compared with postoperative use of a hinged-knee brace, HEF use resulted in fewer failed ligament reconstructions as well as equivalent joint ROM and Lysholm and IKDC scores at final follow-up. This clinical outcome is supported by results of kinematic studies of these hinged devices, which are capable of rigid fixation in all planes except sagittal and can reduce stress on intra-articular and periarticular ligaments when placed on the appropriate flexion-extension axis of the knee.^19,20Unfortunately, the situation is more complicated for subacute or chronic tibial subluxation than for acute subluxation. Maak and colleagues¹⁶ described 3 operative steps that are crucial in obtaining desired outcomes in this setting: complete release of scar tissue, re-creation of knee axis through ACL and PCL reconstruction, and postoperative application of a HEF or knee brace. These recommendations mimic the management course described by Richter and Lobenhoffer¹³ and Simonian and colleagues,¹⁴ who treated chronic fixed posterior tibial subluxations with arthrolysis, ligament reconstruction, and use of HEFs for 6 weeks, supporting postoperative rehabilitation. All cases maintained reduction at follow-up after fixator removal.

It is also possible for small fixed anterior or posterior tibial subluxations to be managed nonoperatively. Strobel and colleagues¹⁵ described a series of 109 patients with fixed posterior subluxations treated at night with posterior tibial support braces. Mean subluxation was reduced from 6.93 mm to 2.58 mm after an average treatment period of 180 days. Although 60% of all subluxations were completely reduced, reductions were significantly more successful for those displaced <10 mm.

Management of subacute or chronic fixed coronal tibial subluxations is yet to be described. In this article, we have reported on acceptable reduction of a subacute medial tibial subluxation with use of a HEF for 6 weeks after arthroscopic débridement of a deformed subacute bucket-handle lateral meniscus tear. Our case report is unique in that it describes use of a HEF alone for the reduction of a subacute tibial subluxation in any plane without the need for more extensive ligament reconstruction.

The injury here was primarily a lateral ligamentous injury. In the nonanatomical repair that was performed, the LCL and the iliotibial band were reattached to the proximal-lateral tibia. Had we started treating this injury from the time of the patient’s accident, then, depending on repair integrity, we might have considered acute augmentation of the anatomical repair of LCL with Larson-type reconstruction of the LCL and the popliteofibular ligament. Alternatively, acute reconstruction of the LCL and popliteus would be considered if the lateral structures were either irreparable or of very poor quality. In addition, had we initially seen the coronal instability/translation, we might have acutely considered either a staged procedure of a multiplanar external fixator or a HEF.

Given the narrowed lateral joint space, the débridement of the lateral meniscus, and the risk of developing posttraumatic arthritis, our patient will probably need total knee arthroplasty (TKA) at some point. We informed her that she had advanced lateral compartment joint space narrowing and arthritic progression and that she would eventually need TKA based on pain or dysfunction. We think the longevity of that TKA will be predictable and good, as she now had improved tibiofemoral alignment and stability of the collateral ligamentous structures. If she had been allowed to maintain the coronally subluxed position, it would have led to medial ligamentous attenuation and would have compromised the success and longevity of the TKA. In essence, a crucial part of the utility of the HEF was improved coronal tibiofemoral alignment and, therefore, decreased abnormal forces on both the repaired lateral ligaments and the native medial ligamentous structures. Although temporary external fixation issues related to infection risk and patient discomfort are recognized,^21-23 use of HEF alone can be part of the treatment considerations for fixed tibial subluxations in any plane when they present after treatment for multiligamentous injury.

Am J Orthop. 2016;45(7):E497-E502. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Dislocation of the knee is a severe injury that usually results from high-energy blunt trauma.¹ Recognition of knee dislocations has increased with expansion of the definition beyond radiographically confirmed loss of tibiofemoral articulation to include injury of multiple knee ligaments with multidirectional joint instability, or the rupture of the anterior and posterior cruciate ligaments (ACL, PCL) when no gross dislocation can be identified² (though knee dislocations without rupture of either ligament have been reported^3,4). Knee dislocations account for 0.02% to 0.2% of orthopedic injuries.⁵ These multiligamentous injuries are rare, but their clinical outcomes are often complicated by arthrofibrosis, pain, and instability, as surgeons contend with the competing interests of long-term joint stability and range of motion (ROM).^6-9

Whereas treatment standards for acute knee dislocations are becoming clearer, treatment of subacute and chronic tibiofemoral dislocations and subluxations is less defined.⁵ Success with articulated external fixation originally across the ankle and elbow inspired interest in its use for the knee.^10-12 Richter and Lobenhoffer¹³ and Simonian and colleagues¹⁴ were the first to report on the postoperative use of a hinged external fixation device to help maintain the reduction of chronic fixed posterior knee dislocations. The literature has even supported nonoperative reduction of small fixed anterior or posterior (sagittal) subluxations with knee bracing alone.^15,16 However, there are no reports on treatment of chronic tibial subluxation in the coronal plane.

We report a case of a hinged-knee external fixator (HEF) used alone to reduce a chronic medial tibia subluxation that presented after initial repair of a knee dislocation sustained in a motor vehicle accident. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 51-year-old healthy woman who was traveling out of state sustained multiple orthopedic injuries in a motor vehicle accident. She had a pelvic fracture, a contralateral femoral shaft fracture, significant multiligamentous damage to the right knee, and a cavitary impaction fracture of the tibial eminence with resultant coronal tibial subluxation. Initial magnetic resonance imaging (MRI) showed the tibia injury likely was the result of varus translation, as the medial femoral condyle impacted the tibial spine, disrupting the ACL (Figures 1A, 1B).

The patient also had disruption of the posterolateral corner (PLC), including a lateral collateral ligament (LCL) fibular avulsion, an iliotibial band avulsion, and a popliteus myotendinous junction tear with an intact biceps femoris tendon. Three weeks after the accident and after the associated polytrauma injuries were stabilized, the patient underwent “en masse” repair of the PLC, at an outside institution, as described by Shelbourne and colleagues¹⁷ with tibial spine and ACL débridement.

On initial presentation to our clinic 5 weeks after injury, x-rays showed progressive medial subluxation of the tibia in relation to the femur with translation of about a third of the tibial width medially (Figures 2A, 2B).

The central tibial defect nearly apposed the medial femoral condyle, consistent with the initial impaction injury with translation in the coronal rather than anteroposterior plane. Additional MRI and computed tomography were performed to better define the bony and ligamentous anatomy (Figures 3A-3C).

They showed an intact en masse lateral repair, an intact superficial medial collateral ligament, a bucket-handle lateral meniscus tear, and absence of the ACL and tibial eminence.

Given the worsening tibial subluxation and resultant instability, the patient was taken to the operating room for examination under anesthesia, and planned closed reduction and spanning external fixation. Fluoroscopy of the lateral translation and external rotation of the tibia allowed us to reduce the joint, with the lateral tibial plateau and lateral femoral condyle relatively but not completely concentric. A rigid spanning multiplanar external fixator was then placed to maintain the knee joint in a more reduced position.

A week later, the patient was taken back to the operating room for arthroscopic evaluation of the knee joint. At the time of her index operation at the outside institution, she had undergone arthroscopic débridement of intra-articular loose bodies and lateral meniscus repair. Now it was found that the meniscus was not healed but had displaced. A bucket-handle lateral meniscus tear appeared to be blocking lateral translation of the tibia, thus impeding complete reduction.

Given the meniscus deformity that resulted from the chronicity of the injury and the resultant subluxation, a sub-total lateral meniscectomy was performed. As the patient was now noted to have an intact medial collateral ligament and an intact en masse lateral repair, we converted the spanning external fixator to a Compass Universal Hinge (Smith & Nephew) to maintain reduction without further ligamentous reconstruction (Figure 4).

As we were able to maintain reduction, we thought bone grafting for stability augmentation was not needed, despite the central tibial defect (analogous to an engaging Hill-Sachs defect in shoulder instability). The HEF allowed knee flexion while maintaining coronal alignment.

After HEF placement, the patient spent a short time recovering at an inpatient rehabilitation facility before starting aggressive twice-a-week outpatient physical therapy. Initially after HEF placement, she could not actively flex the knee to about 40° or fully extend it concentrically. Given these limitations and concern about interval development of arthrofibrosis, manipulation under anesthesia was performed, 3 weeks after surgery, and 90° of flexion was obtained.

When the HEF was removed, 6 weeks after placement, fluoroscopy and radiographs showed maintained tibiofemoral alignment (Figures 5A, 5B).

Six weeks after HEF removal, the patient was ambulating well with a cane, pain was minimal, and knee ROM was up to 110° of flexion. Tibiofemoral stability remained constant—no change in medial or lateral joint space opening. Full-extension radiographs showed medial translation of about 5 mm, which decreased to 1 mm on Rosenberg view. This represents marked improvement over the severe subluxation on initial presentation.

Follow-up over the next months revealed continued improvement in the right lower extremity strength, increased tolerance for physical activity, and stable right medial tibial translation.

A year after HEF removal, imaging showed adequate tibiofemoral alignment (Figures 6A-6C). There was mild to moderate joint space narrowing, lateral more than medial.

At 5-year follow-up, the patient was asymptomatic, had continued coronal and sagittal stability, and was tolerating regular aerobic exercise, including hiking, weight training, and cycling. Physical examination revealed grade 1B Lachman, grade 0 pivot shift, and grade 0 posterior drawer. There was 3 mm increased lateral compartment opening in full extension, which increased to about 6 mm at 30° with endpoint.

Radiographs (Figures 7A-7C) showed stable 2-mm coronal translation and asymptomatic though severe lateral compartment arthritis, likely secondary to the multiligament knee injury and the sub–total lateral meniscectomy performed on top of previous lateral compartment arthritis. Final International Knee Documentation Committee (IKDC) score was 78.2, final Tegner Lysholm Knee Score was 94 (“excellent”), Modified Cincinnati Rating System score was 80 (“excellent”), and Knee Injury and Osteoarthritis Outcome Score was 87.5.

 

Discussion

Although knee dislocations with multiligamentous involvement are rare, their outcomes can be poor. Fortunately, the principles of managing these complex injuries in the acute stage are becoming clearer. In a systematic review, Levy and colleagues¹⁸ found that operative treatment of a dislocated knee within 3 weeks after injury, compared with nonoperative or delayed treatment, resulted in improved functional outcomes. Ligament repair and reconstruction yielded similar outcomes, though repair of the posterolateral corner had a comparatively higher rate of failure. For associated lateral injuries, Shelbourne and colleagues¹⁷ advocated en masse repair in which the healing tissue complex is reattached to the tibia nonanatomically, without dissecting individual structures—a technique used in the original repair of our patient’s injuries.

Originally designed for other joints, hinged external fixators are now occasionally used for rehabilitation after traumatic knee injury. Stannard and colleagues⁹ recently confirmed the utility of the HEF as a supplement to ligament reconstruction for recovery from acute knee dislocation.⁹ Compared with postoperative use of a hinged-knee brace, HEF use resulted in fewer failed ligament reconstructions as well as equivalent joint ROM and Lysholm and IKDC scores at final follow-up. This clinical outcome is supported by results of kinematic studies of these hinged devices, which are capable of rigid fixation in all planes except sagittal and can reduce stress on intra-articular and periarticular ligaments when placed on the appropriate flexion-extension axis of the knee.^19,20Unfortunately, the situation is more complicated for subacute or chronic tibial subluxation than for acute subluxation. Maak and colleagues¹⁶ described 3 operative steps that are crucial in obtaining desired outcomes in this setting: complete release of scar tissue, re-creation of knee axis through ACL and PCL reconstruction, and postoperative application of a HEF or knee brace. These recommendations mimic the management course described by Richter and Lobenhoffer¹³ and Simonian and colleagues,¹⁴ who treated chronic fixed posterior tibial subluxations with arthrolysis, ligament reconstruction, and use of HEFs for 6 weeks, supporting postoperative rehabilitation. All cases maintained reduction at follow-up after fixator removal.

It is also possible for small fixed anterior or posterior tibial subluxations to be managed nonoperatively. Strobel and colleagues¹⁵ described a series of 109 patients with fixed posterior subluxations treated at night with posterior tibial support braces. Mean subluxation was reduced from 6.93 mm to 2.58 mm after an average treatment period of 180 days. Although 60% of all subluxations were completely reduced, reductions were significantly more successful for those displaced <10 mm.

Management of subacute or chronic fixed coronal tibial subluxations is yet to be described. In this article, we have reported on acceptable reduction of a subacute medial tibial subluxation with use of a HEF for 6 weeks after arthroscopic débridement of a deformed subacute bucket-handle lateral meniscus tear. Our case report is unique in that it describes use of a HEF alone for the reduction of a subacute tibial subluxation in any plane without the need for more extensive ligament reconstruction.

The injury here was primarily a lateral ligamentous injury. In the nonanatomical repair that was performed, the LCL and the iliotibial band were reattached to the proximal-lateral tibia. Had we started treating this injury from the time of the patient’s accident, then, depending on repair integrity, we might have considered acute augmentation of the anatomical repair of LCL with Larson-type reconstruction of the LCL and the popliteofibular ligament. Alternatively, acute reconstruction of the LCL and popliteus would be considered if the lateral structures were either irreparable or of very poor quality. In addition, had we initially seen the coronal instability/translation, we might have acutely considered either a staged procedure of a multiplanar external fixator or a HEF.

Given the narrowed lateral joint space, the débridement of the lateral meniscus, and the risk of developing posttraumatic arthritis, our patient will probably need total knee arthroplasty (TKA) at some point. We informed her that she had advanced lateral compartment joint space narrowing and arthritic progression and that she would eventually need TKA based on pain or dysfunction. We think the longevity of that TKA will be predictable and good, as she now had improved tibiofemoral alignment and stability of the collateral ligamentous structures. If she had been allowed to maintain the coronally subluxed position, it would have led to medial ligamentous attenuation and would have compromised the success and longevity of the TKA. In essence, a crucial part of the utility of the HEF was improved coronal tibiofemoral alignment and, therefore, decreased abnormal forces on both the repaired lateral ligaments and the native medial ligamentous structures. Although temporary external fixation issues related to infection risk and patient discomfort are recognized,^21-23 use of HEF alone can be part of the treatment considerations for fixed tibial subluxations in any plane when they present after treatment for multiligamentous injury.

Am J Orthop. 2016;45(7):E497-E502. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The role of vitamin D in general health maintenance is a topic of increasing interest and importance in the medical community. Not only has vitamin D deficiency been linked to a myriad of nonorthopedic maladies, including cancer, diabetes, and cardiovascular disease, but it has demonstrated an adverse effect on musculoskeletal health.¹ Authors have found a correlation between vitamin D deficiency and muscle weakness, fragility fractures, and, most recently, fracture nonunion.¹ Despite the detrimental effects of vitamin D deficiency on musculoskeletal and general health, evidence exists that vitamin D deficiency is surprisingly prevalent.² This deficiency is known to be associated with increasing age, but recent studies have also found alarming rates of deficiency in younger populations.^3,4

Although there has been some discussion regarding optimal serum levels of 25-hydroxyvitamin D, most experts have defined vitamin D deficiency as a 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.⁵ Hollis and Wagner⁵ found increased serum parathyroid hormone and bone resorption and impaired dietary absorption of calcium when 25-hydroxyvitamin D levels were under 32 ng/mL. Given these data, a 25-hydroxyvitamin D level of 21 to 32 ng/mL (52-72 nmol/L) can be considered as indicating a relative insufficiency of vitamin D, and a level of 20 ng/mL or less can be considered as indicating vitamin D deficiency.

Vitamin D plays a vital role in bone metabolism and has been implicated in increased fracture risk and in fracture healing ability. Therefore, documenting the prevalence of vitamin D deficiency in patients with trauma is the first step in raising awareness among orthopedic traumatologists and further developing a screening-and-treatment strategy for vitamin D deficiency in these patients. Steele and colleagues⁶ retrospectively studied 44 patients with high- and low-energy fractures and found an almost 60% prevalence of vitamin D insufficiency. If vitamin D insufficiency is this prevalent, treatment protocols for patients with fractures may require modifications that include routine screening and treatment for low vitamin D levels.

After noting a regular occurrence of hypovitaminosis D in our patient population (independent of age, sex, or medical comorbidities), we conducted a study to determine the prevalence of vitamin D deficiency in a large orthopedic trauma population.

Patients and Methods

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the charts of all patients with a fracture treated by 1 of 4 orthopedic traumatologists within a 21-month period (January 1, 2009 to September 30, 2010). Acute fracture and recorded 25-hydroxyvitamin D level were the primary criteria for study inclusion. Given the concern about vitamin D deficiency, it became common protocol to check the serum 25-hydroxyvitamin D levels of patients with acute fractures during the review period. Exclusion criteria were age under 18 years and presence of vitamin D deficiency risk factors, including renal insufficiency (creatinine level, ≥2 mg/dL), malabsorption, gastrectomy, active liver disease, acute myocardial infarction, alcoholism, anorexia nervosa, and steroid dependency.

During the period studied, 1830 patients over age 18 years were treated by 4 fellowship-trained orthopedic traumatologists. Of these patients, 889 (487 female, 402 male) met the inclusion criteria. Mean age was 53.8 years. Demographic data (age, sex, race, independent living status, comorbid medical conditions, medications) were collected from the patients’ medical records. Clinical data collected were mechanism of injury, fracture location and type, injury date, surgery date and surgical procedure performed (when applicable), and serum 25-hydroxyvitamin D levels.

Statistical Methods

Descriptive statistics (mean, median, mode) were calculated. The χ² test was used when all cell frequencies were more than 5, and the Fisher exact probability test was used when any cell frequency was 5 or less. Prevalence of vitamin D deficiency and insufficiency was calculated in multiple patient populations. Patients were analyzed according to age and sex subgroups.

Definitions

Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.² As the serum test was performed independent of the investigators and with use of standard medical laboratory protocols and techniques, there should be no bias in the results. We had intended to have all patients undergo serum testing during the review period because that was our usual protocol. However, test results were available for only 889 (49%) of the 1830 patients with orthopedic trauma during the review period. Although a false-positive is theoretically possible, this series of orthopedic trauma patients is the largest in the literature and therefore should be more accurate than the previously reported small series.

 

Results

There were no significant (P < .05) age or sex differences in prevalence of vitamin D deficiency or insufficiency in our patient population. Overall prevalence of deficiency/insufficiency was 77.39%, and prevalence of deficiency alone was 39.03% (Table 1).

Overall, patients in the 18- to 25-year age group had the lowest prevalence of deficiency (29.1%; P = .25) and insufficiency (54.7%; P = .08).

Patients in the 36- to 65-year age group had a higher prevalence of deficiency and insufficiency, but neither difference was statistically significant. Table 2 lists prevalence of deficiency and insufficiency by age group.

Women in the 18- to 25-year age group had a lower prevalence of deficiency (25%; P = .41) and insufficiency (41.7%; P = .16) than women in the other age groups (Table 3).

Men in the 18- to 25-year age group had a lower prevalence of insufficiency (59.7%; P = .24) than men in the other age groups (Table 4).

There were no other remarkable age or sex differences in prevalence of deficiency or insufficiency. There did not appear to be any seasonal effect based on injury date and serum 25-hydroxyvitamin D level.

Discussion

We conducted this study to determine the prevalence of vitamin D deficiency in a large population of patients with orthopedic trauma. Results showed that vitamin D deficiency and insufficiency were prevalent in this population, which to our knowledge is the largest studied for vitamin D deficiency. In a 6-month study of 44 fractures, Steele and colleagues⁶ found an overall 60% rate of deficiency/insufficiency. Although their investigation is important—it was the first of its kind to evaluate patients with various fracture types, including those with high-energy causes—its numbers were small, and the period evaluated (June 1, 2006 to February 1, 2007) was short (8 months). Use of that time frame may have led to an underestimate of the prevalence of vitamin D deficiency, as vitamin D levels are higher in late summer because of increased sun exposure. Our study of 889 patients over 21 months allowed for seasonal variability of vitamin D levels. We did not notice a specific difference in patients who were treated during winter vs summer. Furthermore, our 77% prevalence of vitamin D insufficiency and 39% prevalence of vitamin D deficiency indicate how widespread low vitamin D levels are in a large Midwestern orthopedic trauma population. In the Pacific Northwest, Bee and colleagues⁷ studied seasonal differences in patients with surgically treated fractures and found an average difference of 3 ng/mL between winter and summer serum levels. However, the real issue, which should not be overlooked, is that the average 25-hydroxyvitamin D level was under 30 ng/mL in both cohorts (26.4 ng/mL in winter vs 29.8 ng/mL in summer). The emphasis should be that both levels were insufficient and that seasonal variance does not really change prevalence.

With use of the current definitions, it has been estimated that 1 billion people worldwide have vitamin D deficiency or insufficiency, with the elderly and certain ethnic populations at higher risk.^8-10Vitamin D deficiency is a common diagnosis among elderly patients with hip fractures. According to various reports, 60% to 90% of patients treated for hip fractures are deficient or insufficient in vitamin D.^8,9Hypovitaminosis D has also been noted in medical inpatients with and without risks for this deficiency.² Surprisingly, low vitamin D levels are not isolated to the elderly. In Massachusetts, Gordon and colleagues¹¹ found a 52% prevalence of vitamin D deficiency in Hispanic and black adolescents. Nesby-O’Dell and colleagues¹⁰ found that 42% of 15- to 49-year-old black women in the United States had vitamin D deficiency at the end of winter. Bogunovic and colleagues¹² noted 5.5 times higher risk of low vitamin D levels in patients with darker skin tones. Although vitamin D deficiency has been linked to specific races, it frequently occurs in lower-risk populations as well. Sullivan and colleagues⁴ found a 48% prevalence of vitamin D deficiency in white preadolescent girls in Maine. Tangpricha and colleagues³ reported a 32% prevalence of vitamin D deficiency in otherwise fit healthcare providers sampled at a Boston hospital. Bogunovic and colleagues¹² also showed that patients between ages 18 years and 50 years, and men, were more likely to have low vitamin D levels.

Establishing the prevalence of hypovitaminosis D in orthopedic trauma patients is needed in order to raise awareness of the disease and modify screening and treatment protocols. Brinker and O’Connor¹³ found vitamin D deficiency in 68% of patients with fracture nonunions, which suggests that hypovitaminosis D may partly account for difficulty in achieving fracture union. Bogunovic and colleagues¹² found vitamin D insufficiency in 43% of 723 patients who underwent orthopedic surgery. Isolating the 121 patients on the trauma service revealed a 66% prevalence of low vitamin D levels. Our 77% prevalence of low vitamin D levels in 889 patients adds to the evidence that low levels are common in patients with orthopedic trauma. Understanding the importance of vitamin D deficiency can be significant in reducing the risk of complications, including delayed unions and nonunions, associated with treating orthopedic trauma cases.

Although our study indicates an alarming prevalence of insufficient vitamin D levels in our patient population, it does not provide a cause-and-effect link between low serum 25-hydroxyvitamin D levels and risk of fracture or nonunion. However, further investigations may yield clinically relevant data linking hypovitaminosis D with fracture risk. Although we did not include patients with nonunion in this study, new prospective investigations will address nonunions and subgroup analysis of race, fracture type, management type (surgical vs nonsurgical), injury date (to determine seasonal effect), and different treatment regimens.

The primary limitation of this study was its retrospective design. In addition, though we collected vitamin D data from 889 patients with acute fracture, our serum collection protocols were not standardized. Most patients who were admitted during initial orthopedic consultation in the emergency department had serum 25-hydroxyvitamin D levels drawn during their hospital stay, and patients initially treated in an ambulatory setting may not have had serum vitamin D levels drawn for up to 2 weeks after injury (the significance of this delay is unknown). Furthermore, the serum result rate for the overall orthopedic trauma population during the review period was only 49%, which could indicate selection bias. There are multiple explanations for the low rate. As with any new protocol or method, it takes time for the order to become standard practice; in the early stages, individuals can forget to ask for the test. In addition, during the review period, the serum test was also relatively new at our facility, and it was a “send-out” test, which could partly account for the lack of consistency. For example, some specimens were lost, and, in a number of other cases, excluded patients mistakenly had their 1,25-hydroxyvitamin D levels measured and were not comparable to included patients. Nevertheless, our sample of 889 patients with acute fractures remains the largest (by several hundred) reported in the literature.

From a practical standpoint, the present results were useful in updating our treatment protocols. Now we typically treat patients only prophylactically, with 50,000 units of vitamin D₂ for 8 weeks and daily vitamin D₃ and calcium until fracture healing. Patients are encouraged to continue daily vitamin D and calcium supplementation after fracture healing to maintain bone health. Compliance, however, remains a continued challenge and lack thereof can potentially explain the confusing effect of a supplementation protocol on the serum 25-hydroxyvitamin D level.¹⁴ The only patients who are not given prophylactic treatment are those who previously had been denied it (patients with chronic kidney disease or elevated blood calcium levels).

Vitamin D deficiency and insufficiency are prevalent in patients with orthopedic trauma. Studies are needed to further elucidate the relationship between low vitamin D levels and risk of complications. Retrospectively, without compliance monitoring, we have not seen a direct correlation with fracture complications.¹⁵ Our goal here was to increase orthopedic surgeons’ awareness of the problem and of the need to consider addressing low serum vitamin D levels. The treatment is low cost and low risk. The ultimate goal—if there is a prospective direct correlation between low serum vitamin D levels and complications—is to develop treatment strategies that can effectively lower the prevalence of low vitamin D levels.

Am J Orthop. 2016;45(7):E522-E526. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The role of vitamin D in general health maintenance is a topic of increasing interest and importance in the medical community. Not only has vitamin D deficiency been linked to a myriad of nonorthopedic maladies, including cancer, diabetes, and cardiovascular disease, but it has demonstrated an adverse effect on musculoskeletal health.¹ Authors have found a correlation between vitamin D deficiency and muscle weakness, fragility fractures, and, most recently, fracture nonunion.¹ Despite the detrimental effects of vitamin D deficiency on musculoskeletal and general health, evidence exists that vitamin D deficiency is surprisingly prevalent.² This deficiency is known to be associated with increasing age, but recent studies have also found alarming rates of deficiency in younger populations.^3,4

Although there has been some discussion regarding optimal serum levels of 25-hydroxyvitamin D, most experts have defined vitamin D deficiency as a 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.⁵ Hollis and Wagner⁵ found increased serum parathyroid hormone and bone resorption and impaired dietary absorption of calcium when 25-hydroxyvitamin D levels were under 32 ng/mL. Given these data, a 25-hydroxyvitamin D level of 21 to 32 ng/mL (52-72 nmol/L) can be considered as indicating a relative insufficiency of vitamin D, and a level of 20 ng/mL or less can be considered as indicating vitamin D deficiency.

Vitamin D plays a vital role in bone metabolism and has been implicated in increased fracture risk and in fracture healing ability. Therefore, documenting the prevalence of vitamin D deficiency in patients with trauma is the first step in raising awareness among orthopedic traumatologists and further developing a screening-and-treatment strategy for vitamin D deficiency in these patients. Steele and colleagues⁶ retrospectively studied 44 patients with high- and low-energy fractures and found an almost 60% prevalence of vitamin D insufficiency. If vitamin D insufficiency is this prevalent, treatment protocols for patients with fractures may require modifications that include routine screening and treatment for low vitamin D levels.

After noting a regular occurrence of hypovitaminosis D in our patient population (independent of age, sex, or medical comorbidities), we conducted a study to determine the prevalence of vitamin D deficiency in a large orthopedic trauma population.

Patients and Methods

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the charts of all patients with a fracture treated by 1 of 4 orthopedic traumatologists within a 21-month period (January 1, 2009 to September 30, 2010). Acute fracture and recorded 25-hydroxyvitamin D level were the primary criteria for study inclusion. Given the concern about vitamin D deficiency, it became common protocol to check the serum 25-hydroxyvitamin D levels of patients with acute fractures during the review period. Exclusion criteria were age under 18 years and presence of vitamin D deficiency risk factors, including renal insufficiency (creatinine level, ≥2 mg/dL), malabsorption, gastrectomy, active liver disease, acute myocardial infarction, alcoholism, anorexia nervosa, and steroid dependency.

During the period studied, 1830 patients over age 18 years were treated by 4 fellowship-trained orthopedic traumatologists. Of these patients, 889 (487 female, 402 male) met the inclusion criteria. Mean age was 53.8 years. Demographic data (age, sex, race, independent living status, comorbid medical conditions, medications) were collected from the patients’ medical records. Clinical data collected were mechanism of injury, fracture location and type, injury date, surgery date and surgical procedure performed (when applicable), and serum 25-hydroxyvitamin D levels.

Statistical Methods

Descriptive statistics (mean, median, mode) were calculated. The χ² test was used when all cell frequencies were more than 5, and the Fisher exact probability test was used when any cell frequency was 5 or less. Prevalence of vitamin D deficiency and insufficiency was calculated in multiple patient populations. Patients were analyzed according to age and sex subgroups.

Definitions

Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.² As the serum test was performed independent of the investigators and with use of standard medical laboratory protocols and techniques, there should be no bias in the results. We had intended to have all patients undergo serum testing during the review period because that was our usual protocol. However, test results were available for only 889 (49%) of the 1830 patients with orthopedic trauma during the review period. Although a false-positive is theoretically possible, this series of orthopedic trauma patients is the largest in the literature and therefore should be more accurate than the previously reported small series.

 

Results

There were no significant (P < .05) age or sex differences in prevalence of vitamin D deficiency or insufficiency in our patient population. Overall prevalence of deficiency/insufficiency was 77.39%, and prevalence of deficiency alone was 39.03% (Table 1).

Overall, patients in the 18- to 25-year age group had the lowest prevalence of deficiency (29.1%; P = .25) and insufficiency (54.7%; P = .08).

Patients in the 36- to 65-year age group had a higher prevalence of deficiency and insufficiency, but neither difference was statistically significant. Table 2 lists prevalence of deficiency and insufficiency by age group.

Women in the 18- to 25-year age group had a lower prevalence of deficiency (25%; P = .41) and insufficiency (41.7%; P = .16) than women in the other age groups (Table 3).

Men in the 18- to 25-year age group had a lower prevalence of insufficiency (59.7%; P = .24) than men in the other age groups (Table 4).

There were no other remarkable age or sex differences in prevalence of deficiency or insufficiency. There did not appear to be any seasonal effect based on injury date and serum 25-hydroxyvitamin D level.

Discussion

We conducted this study to determine the prevalence of vitamin D deficiency in a large population of patients with orthopedic trauma. Results showed that vitamin D deficiency and insufficiency were prevalent in this population, which to our knowledge is the largest studied for vitamin D deficiency. In a 6-month study of 44 fractures, Steele and colleagues⁶ found an overall 60% rate of deficiency/insufficiency. Although their investigation is important—it was the first of its kind to evaluate patients with various fracture types, including those with high-energy causes—its numbers were small, and the period evaluated (June 1, 2006 to February 1, 2007) was short (8 months). Use of that time frame may have led to an underestimate of the prevalence of vitamin D deficiency, as vitamin D levels are higher in late summer because of increased sun exposure. Our study of 889 patients over 21 months allowed for seasonal variability of vitamin D levels. We did not notice a specific difference in patients who were treated during winter vs summer. Furthermore, our 77% prevalence of vitamin D insufficiency and 39% prevalence of vitamin D deficiency indicate how widespread low vitamin D levels are in a large Midwestern orthopedic trauma population. In the Pacific Northwest, Bee and colleagues⁷ studied seasonal differences in patients with surgically treated fractures and found an average difference of 3 ng/mL between winter and summer serum levels. However, the real issue, which should not be overlooked, is that the average 25-hydroxyvitamin D level was under 30 ng/mL in both cohorts (26.4 ng/mL in winter vs 29.8 ng/mL in summer). The emphasis should be that both levels were insufficient and that seasonal variance does not really change prevalence.

With use of the current definitions, it has been estimated that 1 billion people worldwide have vitamin D deficiency or insufficiency, with the elderly and certain ethnic populations at higher risk.^8-10Vitamin D deficiency is a common diagnosis among elderly patients with hip fractures. According to various reports, 60% to 90% of patients treated for hip fractures are deficient or insufficient in vitamin D.^8,9Hypovitaminosis D has also been noted in medical inpatients with and without risks for this deficiency.² Surprisingly, low vitamin D levels are not isolated to the elderly. In Massachusetts, Gordon and colleagues¹¹ found a 52% prevalence of vitamin D deficiency in Hispanic and black adolescents. Nesby-O’Dell and colleagues¹⁰ found that 42% of 15- to 49-year-old black women in the United States had vitamin D deficiency at the end of winter. Bogunovic and colleagues¹² noted 5.5 times higher risk of low vitamin D levels in patients with darker skin tones. Although vitamin D deficiency has been linked to specific races, it frequently occurs in lower-risk populations as well. Sullivan and colleagues⁴ found a 48% prevalence of vitamin D deficiency in white preadolescent girls in Maine. Tangpricha and colleagues³ reported a 32% prevalence of vitamin D deficiency in otherwise fit healthcare providers sampled at a Boston hospital. Bogunovic and colleagues¹² also showed that patients between ages 18 years and 50 years, and men, were more likely to have low vitamin D levels.

Establishing the prevalence of hypovitaminosis D in orthopedic trauma patients is needed in order to raise awareness of the disease and modify screening and treatment protocols. Brinker and O’Connor¹³ found vitamin D deficiency in 68% of patients with fracture nonunions, which suggests that hypovitaminosis D may partly account for difficulty in achieving fracture union. Bogunovic and colleagues¹² found vitamin D insufficiency in 43% of 723 patients who underwent orthopedic surgery. Isolating the 121 patients on the trauma service revealed a 66% prevalence of low vitamin D levels. Our 77% prevalence of low vitamin D levels in 889 patients adds to the evidence that low levels are common in patients with orthopedic trauma. Understanding the importance of vitamin D deficiency can be significant in reducing the risk of complications, including delayed unions and nonunions, associated with treating orthopedic trauma cases.

Although our study indicates an alarming prevalence of insufficient vitamin D levels in our patient population, it does not provide a cause-and-effect link between low serum 25-hydroxyvitamin D levels and risk of fracture or nonunion. However, further investigations may yield clinically relevant data linking hypovitaminosis D with fracture risk. Although we did not include patients with nonunion in this study, new prospective investigations will address nonunions and subgroup analysis of race, fracture type, management type (surgical vs nonsurgical), injury date (to determine seasonal effect), and different treatment regimens.

The primary limitation of this study was its retrospective design. In addition, though we collected vitamin D data from 889 patients with acute fracture, our serum collection protocols were not standardized. Most patients who were admitted during initial orthopedic consultation in the emergency department had serum 25-hydroxyvitamin D levels drawn during their hospital stay, and patients initially treated in an ambulatory setting may not have had serum vitamin D levels drawn for up to 2 weeks after injury (the significance of this delay is unknown). Furthermore, the serum result rate for the overall orthopedic trauma population during the review period was only 49%, which could indicate selection bias. There are multiple explanations for the low rate. As with any new protocol or method, it takes time for the order to become standard practice; in the early stages, individuals can forget to ask for the test. In addition, during the review period, the serum test was also relatively new at our facility, and it was a “send-out” test, which could partly account for the lack of consistency. For example, some specimens were lost, and, in a number of other cases, excluded patients mistakenly had their 1,25-hydroxyvitamin D levels measured and were not comparable to included patients. Nevertheless, our sample of 889 patients with acute fractures remains the largest (by several hundred) reported in the literature.

From a practical standpoint, the present results were useful in updating our treatment protocols. Now we typically treat patients only prophylactically, with 50,000 units of vitamin D₂ for 8 weeks and daily vitamin D₃ and calcium until fracture healing. Patients are encouraged to continue daily vitamin D and calcium supplementation after fracture healing to maintain bone health. Compliance, however, remains a continued challenge and lack thereof can potentially explain the confusing effect of a supplementation protocol on the serum 25-hydroxyvitamin D level.¹⁴ The only patients who are not given prophylactic treatment are those who previously had been denied it (patients with chronic kidney disease or elevated blood calcium levels).

Vitamin D deficiency and insufficiency are prevalent in patients with orthopedic trauma. Studies are needed to further elucidate the relationship between low vitamin D levels and risk of complications. Retrospectively, without compliance monitoring, we have not seen a direct correlation with fracture complications.¹⁵ Our goal here was to increase orthopedic surgeons’ awareness of the problem and of the need to consider addressing low serum vitamin D levels. The treatment is low cost and low risk. The ultimate goal—if there is a prospective direct correlation between low serum vitamin D levels and complications—is to develop treatment strategies that can effectively lower the prevalence of low vitamin D levels.

Am J Orthop. 2016;45(7):E522-E526. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

The role of vitamin D in general health maintenance is a topic of increasing interest and importance in the medical community. Not only has vitamin D deficiency been linked to a myriad of nonorthopedic maladies, including cancer, diabetes, and cardiovascular disease, but it has demonstrated an adverse effect on musculoskeletal health.¹ Authors have found a correlation between vitamin D deficiency and muscle weakness, fragility fractures, and, most recently, fracture nonunion.¹ Despite the detrimental effects of vitamin D deficiency on musculoskeletal and general health, evidence exists that vitamin D deficiency is surprisingly prevalent.² This deficiency is known to be associated with increasing age, but recent studies have also found alarming rates of deficiency in younger populations.^3,4

Although there has been some discussion regarding optimal serum levels of 25-hydroxyvitamin D, most experts have defined vitamin D deficiency as a 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.⁵ Hollis and Wagner⁵ found increased serum parathyroid hormone and bone resorption and impaired dietary absorption of calcium when 25-hydroxyvitamin D levels were under 32 ng/mL. Given these data, a 25-hydroxyvitamin D level of 21 to 32 ng/mL (52-72 nmol/L) can be considered as indicating a relative insufficiency of vitamin D, and a level of 20 ng/mL or less can be considered as indicating vitamin D deficiency.

Vitamin D plays a vital role in bone metabolism and has been implicated in increased fracture risk and in fracture healing ability. Therefore, documenting the prevalence of vitamin D deficiency in patients with trauma is the first step in raising awareness among orthopedic traumatologists and further developing a screening-and-treatment strategy for vitamin D deficiency in these patients. Steele and colleagues⁶ retrospectively studied 44 patients with high- and low-energy fractures and found an almost 60% prevalence of vitamin D insufficiency. If vitamin D insufficiency is this prevalent, treatment protocols for patients with fractures may require modifications that include routine screening and treatment for low vitamin D levels.

After noting a regular occurrence of hypovitaminosis D in our patient population (independent of age, sex, or medical comorbidities), we conducted a study to determine the prevalence of vitamin D deficiency in a large orthopedic trauma population.

Patients and Methods

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the charts of all patients with a fracture treated by 1 of 4 orthopedic traumatologists within a 21-month period (January 1, 2009 to September 30, 2010). Acute fracture and recorded 25-hydroxyvitamin D level were the primary criteria for study inclusion. Given the concern about vitamin D deficiency, it became common protocol to check the serum 25-hydroxyvitamin D levels of patients with acute fractures during the review period. Exclusion criteria were age under 18 years and presence of vitamin D deficiency risk factors, including renal insufficiency (creatinine level, ≥2 mg/dL), malabsorption, gastrectomy, active liver disease, acute myocardial infarction, alcoholism, anorexia nervosa, and steroid dependency.

During the period studied, 1830 patients over age 18 years were treated by 4 fellowship-trained orthopedic traumatologists. Of these patients, 889 (487 female, 402 male) met the inclusion criteria. Mean age was 53.8 years. Demographic data (age, sex, race, independent living status, comorbid medical conditions, medications) were collected from the patients’ medical records. Clinical data collected were mechanism of injury, fracture location and type, injury date, surgery date and surgical procedure performed (when applicable), and serum 25-hydroxyvitamin D levels.

Statistical Methods

Descriptive statistics (mean, median, mode) were calculated. The χ² test was used when all cell frequencies were more than 5, and the Fisher exact probability test was used when any cell frequency was 5 or less. Prevalence of vitamin D deficiency and insufficiency was calculated in multiple patient populations. Patients were analyzed according to age and sex subgroups.

Definitions

Vitamin D deficiency was defined as a serum 25-hydroxyvitamin D level of 20 ng/mL or less and insufficiency as 21 to 32 ng/mL.² As the serum test was performed independent of the investigators and with use of standard medical laboratory protocols and techniques, there should be no bias in the results. We had intended to have all patients undergo serum testing during the review period because that was our usual protocol. However, test results were available for only 889 (49%) of the 1830 patients with orthopedic trauma during the review period. Although a false-positive is theoretically possible, this series of orthopedic trauma patients is the largest in the literature and therefore should be more accurate than the previously reported small series.

 

Results

There were no significant (P < .05) age or sex differences in prevalence of vitamin D deficiency or insufficiency in our patient population. Overall prevalence of deficiency/insufficiency was 77.39%, and prevalence of deficiency alone was 39.03% (Table 1).

Overall, patients in the 18- to 25-year age group had the lowest prevalence of deficiency (29.1%; P = .25) and insufficiency (54.7%; P = .08).

Patients in the 36- to 65-year age group had a higher prevalence of deficiency and insufficiency, but neither difference was statistically significant. Table 2 lists prevalence of deficiency and insufficiency by age group.

Women in the 18- to 25-year age group had a lower prevalence of deficiency (25%; P = .41) and insufficiency (41.7%; P = .16) than women in the other age groups (Table 3).

Men in the 18- to 25-year age group had a lower prevalence of insufficiency (59.7%; P = .24) than men in the other age groups (Table 4).

There were no other remarkable age or sex differences in prevalence of deficiency or insufficiency. There did not appear to be any seasonal effect based on injury date and serum 25-hydroxyvitamin D level.

Discussion

We conducted this study to determine the prevalence of vitamin D deficiency in a large population of patients with orthopedic trauma. Results showed that vitamin D deficiency and insufficiency were prevalent in this population, which to our knowledge is the largest studied for vitamin D deficiency. In a 6-month study of 44 fractures, Steele and colleagues⁶ found an overall 60% rate of deficiency/insufficiency. Although their investigation is important—it was the first of its kind to evaluate patients with various fracture types, including those with high-energy causes—its numbers were small, and the period evaluated (June 1, 2006 to February 1, 2007) was short (8 months). Use of that time frame may have led to an underestimate of the prevalence of vitamin D deficiency, as vitamin D levels are higher in late summer because of increased sun exposure. Our study of 889 patients over 21 months allowed for seasonal variability of vitamin D levels. We did not notice a specific difference in patients who were treated during winter vs summer. Furthermore, our 77% prevalence of vitamin D insufficiency and 39% prevalence of vitamin D deficiency indicate how widespread low vitamin D levels are in a large Midwestern orthopedic trauma population. In the Pacific Northwest, Bee and colleagues⁷ studied seasonal differences in patients with surgically treated fractures and found an average difference of 3 ng/mL between winter and summer serum levels. However, the real issue, which should not be overlooked, is that the average 25-hydroxyvitamin D level was under 30 ng/mL in both cohorts (26.4 ng/mL in winter vs 29.8 ng/mL in summer). The emphasis should be that both levels were insufficient and that seasonal variance does not really change prevalence.

With use of the current definitions, it has been estimated that 1 billion people worldwide have vitamin D deficiency or insufficiency, with the elderly and certain ethnic populations at higher risk.^8-10Vitamin D deficiency is a common diagnosis among elderly patients with hip fractures. According to various reports, 60% to 90% of patients treated for hip fractures are deficient or insufficient in vitamin D.^8,9Hypovitaminosis D has also been noted in medical inpatients with and without risks for this deficiency.² Surprisingly, low vitamin D levels are not isolated to the elderly. In Massachusetts, Gordon and colleagues¹¹ found a 52% prevalence of vitamin D deficiency in Hispanic and black adolescents. Nesby-O’Dell and colleagues¹⁰ found that 42% of 15- to 49-year-old black women in the United States had vitamin D deficiency at the end of winter. Bogunovic and colleagues¹² noted 5.5 times higher risk of low vitamin D levels in patients with darker skin tones. Although vitamin D deficiency has been linked to specific races, it frequently occurs in lower-risk populations as well. Sullivan and colleagues⁴ found a 48% prevalence of vitamin D deficiency in white preadolescent girls in Maine. Tangpricha and colleagues³ reported a 32% prevalence of vitamin D deficiency in otherwise fit healthcare providers sampled at a Boston hospital. Bogunovic and colleagues¹² also showed that patients between ages 18 years and 50 years, and men, were more likely to have low vitamin D levels.

Establishing the prevalence of hypovitaminosis D in orthopedic trauma patients is needed in order to raise awareness of the disease and modify screening and treatment protocols. Brinker and O’Connor¹³ found vitamin D deficiency in 68% of patients with fracture nonunions, which suggests that hypovitaminosis D may partly account for difficulty in achieving fracture union. Bogunovic and colleagues¹² found vitamin D insufficiency in 43% of 723 patients who underwent orthopedic surgery. Isolating the 121 patients on the trauma service revealed a 66% prevalence of low vitamin D levels. Our 77% prevalence of low vitamin D levels in 889 patients adds to the evidence that low levels are common in patients with orthopedic trauma. Understanding the importance of vitamin D deficiency can be significant in reducing the risk of complications, including delayed unions and nonunions, associated with treating orthopedic trauma cases.

Although our study indicates an alarming prevalence of insufficient vitamin D levels in our patient population, it does not provide a cause-and-effect link between low serum 25-hydroxyvitamin D levels and risk of fracture or nonunion. However, further investigations may yield clinically relevant data linking hypovitaminosis D with fracture risk. Although we did not include patients with nonunion in this study, new prospective investigations will address nonunions and subgroup analysis of race, fracture type, management type (surgical vs nonsurgical), injury date (to determine seasonal effect), and different treatment regimens.

The primary limitation of this study was its retrospective design. In addition, though we collected vitamin D data from 889 patients with acute fracture, our serum collection protocols were not standardized. Most patients who were admitted during initial orthopedic consultation in the emergency department had serum 25-hydroxyvitamin D levels drawn during their hospital stay, and patients initially treated in an ambulatory setting may not have had serum vitamin D levels drawn for up to 2 weeks after injury (the significance of this delay is unknown). Furthermore, the serum result rate for the overall orthopedic trauma population during the review period was only 49%, which could indicate selection bias. There are multiple explanations for the low rate. As with any new protocol or method, it takes time for the order to become standard practice; in the early stages, individuals can forget to ask for the test. In addition, during the review period, the serum test was also relatively new at our facility, and it was a “send-out” test, which could partly account for the lack of consistency. For example, some specimens were lost, and, in a number of other cases, excluded patients mistakenly had their 1,25-hydroxyvitamin D levels measured and were not comparable to included patients. Nevertheless, our sample of 889 patients with acute fractures remains the largest (by several hundred) reported in the literature.

From a practical standpoint, the present results were useful in updating our treatment protocols. Now we typically treat patients only prophylactically, with 50,000 units of vitamin D₂ for 8 weeks and daily vitamin D₃ and calcium until fracture healing. Patients are encouraged to continue daily vitamin D and calcium supplementation after fracture healing to maintain bone health. Compliance, however, remains a continued challenge and lack thereof can potentially explain the confusing effect of a supplementation protocol on the serum 25-hydroxyvitamin D level.¹⁴ The only patients who are not given prophylactic treatment are those who previously had been denied it (patients with chronic kidney disease or elevated blood calcium levels).

Vitamin D deficiency and insufficiency are prevalent in patients with orthopedic trauma. Studies are needed to further elucidate the relationship between low vitamin D levels and risk of complications. Retrospectively, without compliance monitoring, we have not seen a direct correlation with fracture complications.¹⁵ Our goal here was to increase orthopedic surgeons’ awareness of the problem and of the need to consider addressing low serum vitamin D levels. The treatment is low cost and low risk. The ultimate goal—if there is a prospective direct correlation between low serum vitamin D levels and complications—is to develop treatment strategies that can effectively lower the prevalence of low vitamin D levels.

Am J Orthop. 2016;45(7):E522-E526. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Fat embolism syndrome (FES) occurs in long-bone fractures and classically presents with the triad of hypoxia, petechia, and altered mental status, or the criteria of Gurd and Wilson.¹ The Lindeque criteria (femur fracture, pH <7.3, increased work of breathing) are also used.^1,2 FES is a potentially fatal complication, with mortality rates ranging from 10% to 36%.^1,3 FES typically occurs within 24 to 72 hours after initial insult, with one study finding an average of 48.5 hours after injury and an incidence of 0.15% to 2.4%.⁴ The overall FES rate is <1% in retrospective reviews and 11% to 29% in prospective studies.⁵ FES may present without one or all of the Gurd and Wilson criteria,⁶ and cerebral fat embolism (CFE) can be even more difficult to diagnose. Patients with CFE typically present with a wide array of postoperative neurologic deficits, commonly in the 24- to 72-hour window in which FES typically occurs. Correct diagnosis and management of CFE require a high index of suspicion and knowledge of the diagnostic work-up. In the postoperative setting, it can be difficult to distinguish CFE-related neurologic deficits from the normal sequelae of anesthesia, pain medications, and other factors.

In this article, we report the case of a 42-year-old woman who developed CFE after reamed intramedullary nail fixation of femoral and tibial shaft fractures. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 42-year-old woman with no past medical history was injured when a horse reared and fell on her. Initial emergent computed tomography (CT) was negative for intracranial hemorrhage, and injury radiographs were obtained (Figures 1A, 1B).

The next morning, the patient underwent reamed intramedullary nailing of femur and tibia (floating knee injury) through a transpatellar approach in a single operation. Oxygen saturation and vital signs were maintained at normal levels throughout the procedure, and there were no intraoperative complications. Postoperative radiographs were obtained (Figures 1C, 1D).

About 9 hours after surgery and 36 hours after injury, the patient was unresponsive. Vital signs, including oxygen saturation, were within normal limits, but she was unable to verbalize. Physical examination revealed symmetric facial musculature but also generalized weakness and diffuse hypertonicity and hyperreflexia. Initial laboratory results, including complete blood cell count, electrolyte panel, and troponin levels, were unremarkable. Naloxone was administered to rule out opioid overdose. An immediate code stroke and neurology consultation was requested. An emergent CT scan of the brain was negative; an urgent magnetic resonance imaging (MRI) scan showed multiple punctate T2/FLAIR (fluid attenuated inversion recovery) hyperintensities with restricted diffusion, predominantly in a parasagittal white matter distribution (Figure 2).

Findings were consistent with multifocal infarcts secondary to CFE. Hypercoagulability workup, CT with pulmonary embolism (PE) protocol, lumbar puncture, and electrocardiogram (EKG) with bubble study were all negative. There was no PE or patent foramen ovale (PFO). Levetiracetam was started as prophylaxis against seizure activity, and aspirin in the setting of embolic stroke.

The patient slowly and steadily improved. She was verbal by postoperative day 3 (POD-3), upper motor neuron signs resolved by POD-4, encephalopathy resolved by POD-7, and she was discharged to a rehabilitation center. Unresolved post-stroke symptoms included mild visual field deficits in the right eye (20/25 vision, central scotoma) and amnesia regarding the events immediately surrounding the surgery. There were no other neurologic or cognitive deficits. The patient was non-weight-bearing on the operative extremity and ambulating with assistance, and she started range-of-motion exercises. After 1 week, she was discharged home with crutches.

The patient followed up with neurology and ophthalmology for routine post-stroke care. At 2- and 6-month neurology follow-ups, she was still amnestic regarding her acute stroke event but did not exhibit any confusion, memory problems, speech deficits, facial droop, headaches, or weakness. According to neurology, the encephalopathy was completely resolved, and the patient was completely recovered from the event. Levetiracetam and aspirin were discontinued at 2 months. At the 2-month ophthalmology follow-up, the patient had 20/20 vision in both eyes and nearly complete resolution of the central scotoma. Ophthalmology confirmed symptom relief and recommended return to routine eye care and 1-year follow-up.

The patient began weight-bearing as tolerated on POD-14 and had no hardware or other complications. At 6-month orthopedics follow-up, range of motion of the affected knee was 0° to 120°, and rotation, length, and varus/valgus and anteroposterior knee laxity were all symmetric to the contralateral extremity. The patient walked with a cane for balance and had a mild limp. The affected thigh still had mild atrophy, but strength was 5/5 throughout. The patient denied pain or hardware sensitivity in the affected extremity and was very pleased with the result.

 

Discussion

Postoperative Acute Mental Status Change

There are many causes of postoperative mental status change after intramedullary nailing. Change may be cardiogenic, infectious, pharmacologic, or neurologic in origin. Age should be considered in the work-up of postoperative mental status change, as common complications differ between older and younger patients, with geriatric patients at particularly high risk for delirium.

In addition, past medical history is important in determining causes of mental status change, as many conditions (eg, cardiac disease, hypercoagulable state, dementia, polypharmacy) can cause or exacerbate these changes. A systematic approach is recommended for evaluating any patient with an acute mental status change (Figure 3).^1,5,7

Next to be evaluated are vital signs—particularly hypoxia, as isolated tachycardia may simply be a manifestation of pain. The cardiac system is then assessed with EKG and cardiac-specific laboratory tests, including a troponin level test if there is suspicion of myocardial infarction. PE and FES are complications with a higher prevalence in intramedullary nailing, and pulmonary involvement can be ruled out with the CT with PE protocol. Skin examination is important as well, as FES presents with petechial rash in 60% of patients⁸ (rash was absent in our patient’s case). Narcotic overdose is easily ruled out with administration of naloxone. Infection and sepsis can cause mental changes, though more commonly in the elderly and seldom so soon after surgery. Evaluation for infection and sepsis involves urinalysis and culturing of blood, urine, and other bodily fluids. If there is concern about surgical site infection, the postoperative dressing should be immediately removed and the wound examined. Last, neurologic and embolic phenomena can be initially investigated with CT to rule out hemorrhagic stroke. If CT of the brain is negative, MRI should be performed. MRI is the gold standard for diagnosing ischemic stroke and CFE caused by FES.⁹

Prevalence of Fat Embolism Syndrome

Development of intramedullary fat release in patients with long-bone injuries is common. A prospective study found circulating fat globules in 95% of 43 patients with femur fractures.¹⁰ In another study, transesophageal EKG showed cardiac embolism in 62% of patients who had undergone intramedullary nail fixation.¹¹ Despite this high rate, only 0.9% to 2.2% of patients developed symptomatic FES. Risk factors for FES include younger age, multiple fractures, closed fractures, and nonoperative or delayed management of long-bone fractures.² As already mentioned, average time to FES presentation after long-bone fracture is about 48 hours. One study found that FES typically occurs within 24 to 72 hours after initial insult (average, 48.5 hours) and that the incidence of FES is 0.15% in tibia fractures, 0.78% in femur fractures, and 2.4% in multiple long-bone fractures.⁴ The timeline is consistent with the present case—our patient developed symptoms about 36 hours after injury. In addition, other studies have found a higher mortality rate (5%-15%) for patients with bilateral femur fractures than for patients with only one fracture.^7,12,13 Patients with a floating knee injury (ipsilateral tibia and femur fractures) are at higher risk for FES and have higher overall morbidity and mortality rates in comparison with patients with an isolated femur or tibia fracture, though the increased risk has not been quantified.

Review of Case Literature: FES With CFE

Few cases of FES with symptomatic CFE in the setting of long-bone fracture or long-bone surgery have been reported in the literature. There is wide variation in the development of FES with respect to preoperative or postoperative status and mechanism of injury. Duran and colleagues¹⁴ described a 20-year-old man with ipsilateral tibia and femur fractures caused by gunshots. Twenty-four hours after presentation, he developed tonic-clonic seizures and the classic triad of rash, hypoxia, and altered mental status. MRI confirmed CFE secondary to FES. The patient was optimized neurologically before definitive fixation and was discharged with minimal neurologic deficits on POD-27. Chang and colleagues¹⁵ and Yeo and colleagues¹⁶ described CFE in patients who underwent bilateral total knee arthroplasty. Symptoms developed 9 hours and 2 days after surgery, respectively. Both patients had fat emboli in the lungs and brain, underwent intensive care treatment, and recovered from the initial insult. After discharge at 44 days and 2 weeks, respectively, they fully recovered.

Other patients with CFE have had less favorable outcomes. Chen and colleagues⁶ reported the case of a 31-year-old man who sustained closed femur and tibia fractures in an automobile collision and experienced an acute decline in neurologic status 1 hour after arrival in the emergency department. The patient was intubated, CFE was diagnosed on the basis of MRI findings, and the orthopedic injuries were treated with external fixation. After 2 weeks, the patient was discharged with persistent neurologic deficits and the need for long-term tube feeding. Walshe and colleagues¹⁷ reported the case of a 19-year-old woman who sustained multiple long-bone injuries and traumatic brain injury and showed fat emboli on MRI. The patient experienced brain herniation while in the intensive care unit and later was declared brain-dead. According to the literature, it is important to maintain high suspicion for FES and possible CFE in the setting of high-energy fracture but also to be aware that FES may develop even with nondisplaced fracture or with reaming of the intramedullary canal in elective total joint arthroplasty.¹⁸

 

Pathophysiology of Fat Embolism Syndrome

The pathophysiology of FES and specifically of CFE is not widely understood. Two main theories on the development of FES have been advanced.

The mechanical theory suggests that exposing intramedullary long-bone contents allows fat to mobilize into the bloodstream.¹⁹ This occurs in the setting of long-bone fracture and in canal preparation during joint replacement surgery. More fat extravasates into the venous system after femur fracture than after tibia fracture, which accounts for the higher risk for FES in femoral shaft fractures and the even higher risk in concomitant femur and tibia fractures.⁴ In addition to there being a risk of fat embolism from the fracture itself, placing the patient in traction or reaming the intramedullary canal may exacerbate this effect by increased extravasation of fat from the medullary canal. With extravasation of fatty bone marrow into the venous system, fat emboli are free to travel back to the lungs, where they can cause infarcts within the lung parenchyma.

In the mechanical theory, presence of PFO may allow fat globules to pass into the systemic circulation and cause end-organ emboli. In the event of cerebral emboli, neurologic symptoms may vary widely and may include diffuse encephalopathy and global deficits.²⁰ Dog studies have found a possible mechanism for CFE in the absence of PFO. One such study, which used femoral pressurization to replicate cemented femoral arthroplasty, found that many fat globules had traversed the lungs after release into bone marrow,²¹ supporting the theory that fat droplets can traverse the pulmonary system without sequestration in the lung parenchyma. Riding and colleagues²² reported finding pulmonary arteriovenous shunts, which are thought to allow CFE to occur in the absence of PFO. More studies are needed to determine the prevalence of shunts and their overall contribution to CFE development in patients with long-bone fracture.

The biochemical theory holds that bodily trauma induces the release of free fatty acids (FFAs) from the capillaries into the bloodstream.²³ This stress response is mediated by catecholamines, which activate the adenyl cyclase pathway, which activates lipase, which hydrolyzes stored triglycerides to FFAs and glycerol. The concentration of circulating FFA was increased in 9 of 10 patients in one study.²³ Increased FFAs in the bloodstream can accelerate local and end-organ clotting, leading to thrombocytopenia and endothelial injury. In addition, patients with hypercoagulable diseases are at higher risk for postoperative thromboembolism.²⁴ However, with a negative hypercoagulable work-up and with negative chest helical CT and EKG, which did not demonstrate PFO, the explanation for CFE in our patient may more likely reside with the arteriovenous shunt theory proposed by Riding and colleagues.²²

Diagnosis and Treatment

Proper care of orthopedic patients who potentially have FES/CFE involves prompt diagnosis, immediate symptomatic care, and early coordination with neurology and medical services to rule out other causes of symptoms. Obtaining advanced imaging to rule out other potential causes and to confirm the diagnosis is crucial. The patient in this case report did not exhibit any focal neurologic deficits, but emergent CT of the brain was indicated to rule out a hemorrhagic event. If a stroke secondary to FES is clinically suspected, MRI should be obtained as soon as possible. Multiple studies have found that the “starfield” pattern, which is best seen as multiple punctate hyperintensities on T2 imaging, is the typical radiographic manifestation of CFE.⁹ This applies to patients who are in the 24- to 72-hour window after long-bone fracture or fixation and who fit Gurd and Wilson¹ criteria or Lindeque^1,2criteria, or who exhibit a change in mental status but have a negative CT scan of the brain, as was the case with our patient. Once the diagnosis is made, treatment involves addressing the symptoms (Figure 4).

Hypoxia should be treated with supplementary oxygen; if acute respiratory distress syndrome develops, intubation and mechanical ventilation may be required. Patients with embolic phenomena causing CFE should receive aspirin for stroke prophylaxis and an antiepileptic for seizure prophylaxis. The best way to treat FES and CFE remains prevention with early operative fixation. If prevention fails, timely supportive care can help; a majority of patients who receive such care recover from neurologic and pulmonary sequelae (overall mortality rate, 10%).²⁵

Fat Embolism Syndrome in Reamed and Unreamed Nailing

Over the past several decades, the number of long bones fixed with intramedullary nails has increased significantly.²⁶ There is debate regarding whether use of reamed intramedullary nails increases the risk of fat emboli relative to use of unreamed nails, but multiple studies have found no significant difference.^26,27 Pulmonary shunting occurs in both reamed and unreamed nailing; neither technique has an advantage in terms of cardiopulmonary complications. In multiple studies, reamed nails have the advantage of improved healing rates.²⁷ A sheep study compared reamed and unreamed femoral nailing.²⁸ After nailing, sheep lungs were examined histologically for the presence of bone marrow fat embolism. The embolism rate was higher with unreamed nailing (10.25%) than with reamed nailing (6.66%). One large study of the adverse effects of reamed and unreamed nailing in 1226 patients with tibial shaft fracture found that those with open fractures had higher rates of a negative event (nonunion, infection, fasciotomy, hardware failure, need for dynamization) after reamed nailing.²⁹ Patients with closed fractures had fewer events after reamed nailing. The authors concluded there is a potential benefit in outcome with reamed intramedullary nailing in patients with closed tibial shaft fractures, but they did not comment on development of FES. In a study of the effect of subject position on intramedullary pressure and fat embolism release, dogs were positioned either supine or lateral for tibial and femoral reaming.³⁰ The authors measured various physiologic parameters, including cardiac output, pulmonary arterial wedge pressure, arterial and venous blood gas, and blood cell counts. There were no statistically significant differences in values between the 2 groups in any variable, indicating that position does not affect FES development in the orthopedic trauma setting.

 

Conclusion

FES and CFE are potential devastating sequelae of both long-bone fracture and long-bone instrumentation. It is important to recognize these entities in the acute setting and to consider them in the differential diagnosis of a trauma or postoperative patient who experiences sudden onset of altered mental status with or without dyspnea or a petechial rash. If CFE is suspected, early advanced imaging (including urgent MRI) should be obtained with rapid involvement of a multidisciplinary team that can optimize the chance for successful recovery of both neurologic and physical function. The best treatment, early prevention and diagnosis, maximizes care of symptoms. As is evidenced in this case report, rapid diagnosis and treatment often result in recovery from a majority of the symptoms of FES and CFE.

Am J Orthop. 2016;45(7):E515-E521. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Fat embolism syndrome (FES) occurs in long-bone fractures and classically presents with the triad of hypoxia, petechia, and altered mental status, or the criteria of Gurd and Wilson.¹ The Lindeque criteria (femur fracture, pH <7.3, increased work of breathing) are also used.^1,2 FES is a potentially fatal complication, with mortality rates ranging from 10% to 36%.^1,3 FES typically occurs within 24 to 72 hours after initial insult, with one study finding an average of 48.5 hours after injury and an incidence of 0.15% to 2.4%.⁴ The overall FES rate is <1% in retrospective reviews and 11% to 29% in prospective studies.⁵ FES may present without one or all of the Gurd and Wilson criteria,⁶ and cerebral fat embolism (CFE) can be even more difficult to diagnose. Patients with CFE typically present with a wide array of postoperative neurologic deficits, commonly in the 24- to 72-hour window in which FES typically occurs. Correct diagnosis and management of CFE require a high index of suspicion and knowledge of the diagnostic work-up. In the postoperative setting, it can be difficult to distinguish CFE-related neurologic deficits from the normal sequelae of anesthesia, pain medications, and other factors.

In this article, we report the case of a 42-year-old woman who developed CFE after reamed intramedullary nail fixation of femoral and tibial shaft fractures. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 42-year-old woman with no past medical history was injured when a horse reared and fell on her. Initial emergent computed tomography (CT) was negative for intracranial hemorrhage, and injury radiographs were obtained (Figures 1A, 1B).

The next morning, the patient underwent reamed intramedullary nailing of femur and tibia (floating knee injury) through a transpatellar approach in a single operation. Oxygen saturation and vital signs were maintained at normal levels throughout the procedure, and there were no intraoperative complications. Postoperative radiographs were obtained (Figures 1C, 1D).

About 9 hours after surgery and 36 hours after injury, the patient was unresponsive. Vital signs, including oxygen saturation, were within normal limits, but she was unable to verbalize. Physical examination revealed symmetric facial musculature but also generalized weakness and diffuse hypertonicity and hyperreflexia. Initial laboratory results, including complete blood cell count, electrolyte panel, and troponin levels, were unremarkable. Naloxone was administered to rule out opioid overdose. An immediate code stroke and neurology consultation was requested. An emergent CT scan of the brain was negative; an urgent magnetic resonance imaging (MRI) scan showed multiple punctate T2/FLAIR (fluid attenuated inversion recovery) hyperintensities with restricted diffusion, predominantly in a parasagittal white matter distribution (Figure 2).

Findings were consistent with multifocal infarcts secondary to CFE. Hypercoagulability workup, CT with pulmonary embolism (PE) protocol, lumbar puncture, and electrocardiogram (EKG) with bubble study were all negative. There was no PE or patent foramen ovale (PFO). Levetiracetam was started as prophylaxis against seizure activity, and aspirin in the setting of embolic stroke.

The patient slowly and steadily improved. She was verbal by postoperative day 3 (POD-3), upper motor neuron signs resolved by POD-4, encephalopathy resolved by POD-7, and she was discharged to a rehabilitation center. Unresolved post-stroke symptoms included mild visual field deficits in the right eye (20/25 vision, central scotoma) and amnesia regarding the events immediately surrounding the surgery. There were no other neurologic or cognitive deficits. The patient was non-weight-bearing on the operative extremity and ambulating with assistance, and she started range-of-motion exercises. After 1 week, she was discharged home with crutches.

The patient followed up with neurology and ophthalmology for routine post-stroke care. At 2- and 6-month neurology follow-ups, she was still amnestic regarding her acute stroke event but did not exhibit any confusion, memory problems, speech deficits, facial droop, headaches, or weakness. According to neurology, the encephalopathy was completely resolved, and the patient was completely recovered from the event. Levetiracetam and aspirin were discontinued at 2 months. At the 2-month ophthalmology follow-up, the patient had 20/20 vision in both eyes and nearly complete resolution of the central scotoma. Ophthalmology confirmed symptom relief and recommended return to routine eye care and 1-year follow-up.

The patient began weight-bearing as tolerated on POD-14 and had no hardware or other complications. At 6-month orthopedics follow-up, range of motion of the affected knee was 0° to 120°, and rotation, length, and varus/valgus and anteroposterior knee laxity were all symmetric to the contralateral extremity. The patient walked with a cane for balance and had a mild limp. The affected thigh still had mild atrophy, but strength was 5/5 throughout. The patient denied pain or hardware sensitivity in the affected extremity and was very pleased with the result.

 

Discussion

Postoperative Acute Mental Status Change

There are many causes of postoperative mental status change after intramedullary nailing. Change may be cardiogenic, infectious, pharmacologic, or neurologic in origin. Age should be considered in the work-up of postoperative mental status change, as common complications differ between older and younger patients, with geriatric patients at particularly high risk for delirium.

In addition, past medical history is important in determining causes of mental status change, as many conditions (eg, cardiac disease, hypercoagulable state, dementia, polypharmacy) can cause or exacerbate these changes. A systematic approach is recommended for evaluating any patient with an acute mental status change (Figure 3).^1,5,7

Next to be evaluated are vital signs—particularly hypoxia, as isolated tachycardia may simply be a manifestation of pain. The cardiac system is then assessed with EKG and cardiac-specific laboratory tests, including a troponin level test if there is suspicion of myocardial infarction. PE and FES are complications with a higher prevalence in intramedullary nailing, and pulmonary involvement can be ruled out with the CT with PE protocol. Skin examination is important as well, as FES presents with petechial rash in 60% of patients⁸ (rash was absent in our patient’s case). Narcotic overdose is easily ruled out with administration of naloxone. Infection and sepsis can cause mental changes, though more commonly in the elderly and seldom so soon after surgery. Evaluation for infection and sepsis involves urinalysis and culturing of blood, urine, and other bodily fluids. If there is concern about surgical site infection, the postoperative dressing should be immediately removed and the wound examined. Last, neurologic and embolic phenomena can be initially investigated with CT to rule out hemorrhagic stroke. If CT of the brain is negative, MRI should be performed. MRI is the gold standard for diagnosing ischemic stroke and CFE caused by FES.⁹

Prevalence of Fat Embolism Syndrome

Development of intramedullary fat release in patients with long-bone injuries is common. A prospective study found circulating fat globules in 95% of 43 patients with femur fractures.¹⁰ In another study, transesophageal EKG showed cardiac embolism in 62% of patients who had undergone intramedullary nail fixation.¹¹ Despite this high rate, only 0.9% to 2.2% of patients developed symptomatic FES. Risk factors for FES include younger age, multiple fractures, closed fractures, and nonoperative or delayed management of long-bone fractures.² As already mentioned, average time to FES presentation after long-bone fracture is about 48 hours. One study found that FES typically occurs within 24 to 72 hours after initial insult (average, 48.5 hours) and that the incidence of FES is 0.15% in tibia fractures, 0.78% in femur fractures, and 2.4% in multiple long-bone fractures.⁴ The timeline is consistent with the present case—our patient developed symptoms about 36 hours after injury. In addition, other studies have found a higher mortality rate (5%-15%) for patients with bilateral femur fractures than for patients with only one fracture.^7,12,13 Patients with a floating knee injury (ipsilateral tibia and femur fractures) are at higher risk for FES and have higher overall morbidity and mortality rates in comparison with patients with an isolated femur or tibia fracture, though the increased risk has not been quantified.

Review of Case Literature: FES With CFE

Few cases of FES with symptomatic CFE in the setting of long-bone fracture or long-bone surgery have been reported in the literature. There is wide variation in the development of FES with respect to preoperative or postoperative status and mechanism of injury. Duran and colleagues¹⁴ described a 20-year-old man with ipsilateral tibia and femur fractures caused by gunshots. Twenty-four hours after presentation, he developed tonic-clonic seizures and the classic triad of rash, hypoxia, and altered mental status. MRI confirmed CFE secondary to FES. The patient was optimized neurologically before definitive fixation and was discharged with minimal neurologic deficits on POD-27. Chang and colleagues¹⁵ and Yeo and colleagues¹⁶ described CFE in patients who underwent bilateral total knee arthroplasty. Symptoms developed 9 hours and 2 days after surgery, respectively. Both patients had fat emboli in the lungs and brain, underwent intensive care treatment, and recovered from the initial insult. After discharge at 44 days and 2 weeks, respectively, they fully recovered.

Other patients with CFE have had less favorable outcomes. Chen and colleagues⁶ reported the case of a 31-year-old man who sustained closed femur and tibia fractures in an automobile collision and experienced an acute decline in neurologic status 1 hour after arrival in the emergency department. The patient was intubated, CFE was diagnosed on the basis of MRI findings, and the orthopedic injuries were treated with external fixation. After 2 weeks, the patient was discharged with persistent neurologic deficits and the need for long-term tube feeding. Walshe and colleagues¹⁷ reported the case of a 19-year-old woman who sustained multiple long-bone injuries and traumatic brain injury and showed fat emboli on MRI. The patient experienced brain herniation while in the intensive care unit and later was declared brain-dead. According to the literature, it is important to maintain high suspicion for FES and possible CFE in the setting of high-energy fracture but also to be aware that FES may develop even with nondisplaced fracture or with reaming of the intramedullary canal in elective total joint arthroplasty.¹⁸

 

Pathophysiology of Fat Embolism Syndrome

The pathophysiology of FES and specifically of CFE is not widely understood. Two main theories on the development of FES have been advanced.

The mechanical theory suggests that exposing intramedullary long-bone contents allows fat to mobilize into the bloodstream.¹⁹ This occurs in the setting of long-bone fracture and in canal preparation during joint replacement surgery. More fat extravasates into the venous system after femur fracture than after tibia fracture, which accounts for the higher risk for FES in femoral shaft fractures and the even higher risk in concomitant femur and tibia fractures.⁴ In addition to there being a risk of fat embolism from the fracture itself, placing the patient in traction or reaming the intramedullary canal may exacerbate this effect by increased extravasation of fat from the medullary canal. With extravasation of fatty bone marrow into the venous system, fat emboli are free to travel back to the lungs, where they can cause infarcts within the lung parenchyma.

In the mechanical theory, presence of PFO may allow fat globules to pass into the systemic circulation and cause end-organ emboli. In the event of cerebral emboli, neurologic symptoms may vary widely and may include diffuse encephalopathy and global deficits.²⁰ Dog studies have found a possible mechanism for CFE in the absence of PFO. One such study, which used femoral pressurization to replicate cemented femoral arthroplasty, found that many fat globules had traversed the lungs after release into bone marrow,²¹ supporting the theory that fat droplets can traverse the pulmonary system without sequestration in the lung parenchyma. Riding and colleagues²² reported finding pulmonary arteriovenous shunts, which are thought to allow CFE to occur in the absence of PFO. More studies are needed to determine the prevalence of shunts and their overall contribution to CFE development in patients with long-bone fracture.

The biochemical theory holds that bodily trauma induces the release of free fatty acids (FFAs) from the capillaries into the bloodstream.²³ This stress response is mediated by catecholamines, which activate the adenyl cyclase pathway, which activates lipase, which hydrolyzes stored triglycerides to FFAs and glycerol. The concentration of circulating FFA was increased in 9 of 10 patients in one study.²³ Increased FFAs in the bloodstream can accelerate local and end-organ clotting, leading to thrombocytopenia and endothelial injury. In addition, patients with hypercoagulable diseases are at higher risk for postoperative thromboembolism.²⁴ However, with a negative hypercoagulable work-up and with negative chest helical CT and EKG, which did not demonstrate PFO, the explanation for CFE in our patient may more likely reside with the arteriovenous shunt theory proposed by Riding and colleagues.²²

Diagnosis and Treatment

Proper care of orthopedic patients who potentially have FES/CFE involves prompt diagnosis, immediate symptomatic care, and early coordination with neurology and medical services to rule out other causes of symptoms. Obtaining advanced imaging to rule out other potential causes and to confirm the diagnosis is crucial. The patient in this case report did not exhibit any focal neurologic deficits, but emergent CT of the brain was indicated to rule out a hemorrhagic event. If a stroke secondary to FES is clinically suspected, MRI should be obtained as soon as possible. Multiple studies have found that the “starfield” pattern, which is best seen as multiple punctate hyperintensities on T2 imaging, is the typical radiographic manifestation of CFE.⁹ This applies to patients who are in the 24- to 72-hour window after long-bone fracture or fixation and who fit Gurd and Wilson¹ criteria or Lindeque^1,2criteria, or who exhibit a change in mental status but have a negative CT scan of the brain, as was the case with our patient. Once the diagnosis is made, treatment involves addressing the symptoms (Figure 4).

Hypoxia should be treated with supplementary oxygen; if acute respiratory distress syndrome develops, intubation and mechanical ventilation may be required. Patients with embolic phenomena causing CFE should receive aspirin for stroke prophylaxis and an antiepileptic for seizure prophylaxis. The best way to treat FES and CFE remains prevention with early operative fixation. If prevention fails, timely supportive care can help; a majority of patients who receive such care recover from neurologic and pulmonary sequelae (overall mortality rate, 10%).²⁵

Fat Embolism Syndrome in Reamed and Unreamed Nailing

Over the past several decades, the number of long bones fixed with intramedullary nails has increased significantly.²⁶ There is debate regarding whether use of reamed intramedullary nails increases the risk of fat emboli relative to use of unreamed nails, but multiple studies have found no significant difference.^26,27 Pulmonary shunting occurs in both reamed and unreamed nailing; neither technique has an advantage in terms of cardiopulmonary complications. In multiple studies, reamed nails have the advantage of improved healing rates.²⁷ A sheep study compared reamed and unreamed femoral nailing.²⁸ After nailing, sheep lungs were examined histologically for the presence of bone marrow fat embolism. The embolism rate was higher with unreamed nailing (10.25%) than with reamed nailing (6.66%). One large study of the adverse effects of reamed and unreamed nailing in 1226 patients with tibial shaft fracture found that those with open fractures had higher rates of a negative event (nonunion, infection, fasciotomy, hardware failure, need for dynamization) after reamed nailing.²⁹ Patients with closed fractures had fewer events after reamed nailing. The authors concluded there is a potential benefit in outcome with reamed intramedullary nailing in patients with closed tibial shaft fractures, but they did not comment on development of FES. In a study of the effect of subject position on intramedullary pressure and fat embolism release, dogs were positioned either supine or lateral for tibial and femoral reaming.³⁰ The authors measured various physiologic parameters, including cardiac output, pulmonary arterial wedge pressure, arterial and venous blood gas, and blood cell counts. There were no statistically significant differences in values between the 2 groups in any variable, indicating that position does not affect FES development in the orthopedic trauma setting.

 

Conclusion

FES and CFE are potential devastating sequelae of both long-bone fracture and long-bone instrumentation. It is important to recognize these entities in the acute setting and to consider them in the differential diagnosis of a trauma or postoperative patient who experiences sudden onset of altered mental status with or without dyspnea or a petechial rash. If CFE is suspected, early advanced imaging (including urgent MRI) should be obtained with rapid involvement of a multidisciplinary team that can optimize the chance for successful recovery of both neurologic and physical function. The best treatment, early prevention and diagnosis, maximizes care of symptoms. As is evidenced in this case report, rapid diagnosis and treatment often result in recovery from a majority of the symptoms of FES and CFE.

Am J Orthop. 2016;45(7):E515-E521. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Fat embolism syndrome (FES) occurs in long-bone fractures and classically presents with the triad of hypoxia, petechia, and altered mental status, or the criteria of Gurd and Wilson.¹ The Lindeque criteria (femur fracture, pH <7.3, increased work of breathing) are also used.^1,2 FES is a potentially fatal complication, with mortality rates ranging from 10% to 36%.^1,3 FES typically occurs within 24 to 72 hours after initial insult, with one study finding an average of 48.5 hours after injury and an incidence of 0.15% to 2.4%.⁴ The overall FES rate is <1% in retrospective reviews and 11% to 29% in prospective studies.⁵ FES may present without one or all of the Gurd and Wilson criteria,⁶ and cerebral fat embolism (CFE) can be even more difficult to diagnose. Patients with CFE typically present with a wide array of postoperative neurologic deficits, commonly in the 24- to 72-hour window in which FES typically occurs. Correct diagnosis and management of CFE require a high index of suspicion and knowledge of the diagnostic work-up. In the postoperative setting, it can be difficult to distinguish CFE-related neurologic deficits from the normal sequelae of anesthesia, pain medications, and other factors.

In this article, we report the case of a 42-year-old woman who developed CFE after reamed intramedullary nail fixation of femoral and tibial shaft fractures. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 42-year-old woman with no past medical history was injured when a horse reared and fell on her. Initial emergent computed tomography (CT) was negative for intracranial hemorrhage, and injury radiographs were obtained (Figures 1A, 1B).

The next morning, the patient underwent reamed intramedullary nailing of femur and tibia (floating knee injury) through a transpatellar approach in a single operation. Oxygen saturation and vital signs were maintained at normal levels throughout the procedure, and there were no intraoperative complications. Postoperative radiographs were obtained (Figures 1C, 1D).

About 9 hours after surgery and 36 hours after injury, the patient was unresponsive. Vital signs, including oxygen saturation, were within normal limits, but she was unable to verbalize. Physical examination revealed symmetric facial musculature but also generalized weakness and diffuse hypertonicity and hyperreflexia. Initial laboratory results, including complete blood cell count, electrolyte panel, and troponin levels, were unremarkable. Naloxone was administered to rule out opioid overdose. An immediate code stroke and neurology consultation was requested. An emergent CT scan of the brain was negative; an urgent magnetic resonance imaging (MRI) scan showed multiple punctate T2/FLAIR (fluid attenuated inversion recovery) hyperintensities with restricted diffusion, predominantly in a parasagittal white matter distribution (Figure 2).

Findings were consistent with multifocal infarcts secondary to CFE. Hypercoagulability workup, CT with pulmonary embolism (PE) protocol, lumbar puncture, and electrocardiogram (EKG) with bubble study were all negative. There was no PE or patent foramen ovale (PFO). Levetiracetam was started as prophylaxis against seizure activity, and aspirin in the setting of embolic stroke.

The patient slowly and steadily improved. She was verbal by postoperative day 3 (POD-3), upper motor neuron signs resolved by POD-4, encephalopathy resolved by POD-7, and she was discharged to a rehabilitation center. Unresolved post-stroke symptoms included mild visual field deficits in the right eye (20/25 vision, central scotoma) and amnesia regarding the events immediately surrounding the surgery. There were no other neurologic or cognitive deficits. The patient was non-weight-bearing on the operative extremity and ambulating with assistance, and she started range-of-motion exercises. After 1 week, she was discharged home with crutches.

The patient followed up with neurology and ophthalmology for routine post-stroke care. At 2- and 6-month neurology follow-ups, she was still amnestic regarding her acute stroke event but did not exhibit any confusion, memory problems, speech deficits, facial droop, headaches, or weakness. According to neurology, the encephalopathy was completely resolved, and the patient was completely recovered from the event. Levetiracetam and aspirin were discontinued at 2 months. At the 2-month ophthalmology follow-up, the patient had 20/20 vision in both eyes and nearly complete resolution of the central scotoma. Ophthalmology confirmed symptom relief and recommended return to routine eye care and 1-year follow-up.

The patient began weight-bearing as tolerated on POD-14 and had no hardware or other complications. At 6-month orthopedics follow-up, range of motion of the affected knee was 0° to 120°, and rotation, length, and varus/valgus and anteroposterior knee laxity were all symmetric to the contralateral extremity. The patient walked with a cane for balance and had a mild limp. The affected thigh still had mild atrophy, but strength was 5/5 throughout. The patient denied pain or hardware sensitivity in the affected extremity and was very pleased with the result.

 

Discussion

Postoperative Acute Mental Status Change

There are many causes of postoperative mental status change after intramedullary nailing. Change may be cardiogenic, infectious, pharmacologic, or neurologic in origin. Age should be considered in the work-up of postoperative mental status change, as common complications differ between older and younger patients, with geriatric patients at particularly high risk for delirium.

In addition, past medical history is important in determining causes of mental status change, as many conditions (eg, cardiac disease, hypercoagulable state, dementia, polypharmacy) can cause or exacerbate these changes. A systematic approach is recommended for evaluating any patient with an acute mental status change (Figure 3).^1,5,7

Next to be evaluated are vital signs—particularly hypoxia, as isolated tachycardia may simply be a manifestation of pain. The cardiac system is then assessed with EKG and cardiac-specific laboratory tests, including a troponin level test if there is suspicion of myocardial infarction. PE and FES are complications with a higher prevalence in intramedullary nailing, and pulmonary involvement can be ruled out with the CT with PE protocol. Skin examination is important as well, as FES presents with petechial rash in 60% of patients⁸ (rash was absent in our patient’s case). Narcotic overdose is easily ruled out with administration of naloxone. Infection and sepsis can cause mental changes, though more commonly in the elderly and seldom so soon after surgery. Evaluation for infection and sepsis involves urinalysis and culturing of blood, urine, and other bodily fluids. If there is concern about surgical site infection, the postoperative dressing should be immediately removed and the wound examined. Last, neurologic and embolic phenomena can be initially investigated with CT to rule out hemorrhagic stroke. If CT of the brain is negative, MRI should be performed. MRI is the gold standard for diagnosing ischemic stroke and CFE caused by FES.⁹

Prevalence of Fat Embolism Syndrome

Development of intramedullary fat release in patients with long-bone injuries is common. A prospective study found circulating fat globules in 95% of 43 patients with femur fractures.¹⁰ In another study, transesophageal EKG showed cardiac embolism in 62% of patients who had undergone intramedullary nail fixation.¹¹ Despite this high rate, only 0.9% to 2.2% of patients developed symptomatic FES. Risk factors for FES include younger age, multiple fractures, closed fractures, and nonoperative or delayed management of long-bone fractures.² As already mentioned, average time to FES presentation after long-bone fracture is about 48 hours. One study found that FES typically occurs within 24 to 72 hours after initial insult (average, 48.5 hours) and that the incidence of FES is 0.15% in tibia fractures, 0.78% in femur fractures, and 2.4% in multiple long-bone fractures.⁴ The timeline is consistent with the present case—our patient developed symptoms about 36 hours after injury. In addition, other studies have found a higher mortality rate (5%-15%) for patients with bilateral femur fractures than for patients with only one fracture.^7,12,13 Patients with a floating knee injury (ipsilateral tibia and femur fractures) are at higher risk for FES and have higher overall morbidity and mortality rates in comparison with patients with an isolated femur or tibia fracture, though the increased risk has not been quantified.

Review of Case Literature: FES With CFE

Few cases of FES with symptomatic CFE in the setting of long-bone fracture or long-bone surgery have been reported in the literature. There is wide variation in the development of FES with respect to preoperative or postoperative status and mechanism of injury. Duran and colleagues¹⁴ described a 20-year-old man with ipsilateral tibia and femur fractures caused by gunshots. Twenty-four hours after presentation, he developed tonic-clonic seizures and the classic triad of rash, hypoxia, and altered mental status. MRI confirmed CFE secondary to FES. The patient was optimized neurologically before definitive fixation and was discharged with minimal neurologic deficits on POD-27. Chang and colleagues¹⁵ and Yeo and colleagues¹⁶ described CFE in patients who underwent bilateral total knee arthroplasty. Symptoms developed 9 hours and 2 days after surgery, respectively. Both patients had fat emboli in the lungs and brain, underwent intensive care treatment, and recovered from the initial insult. After discharge at 44 days and 2 weeks, respectively, they fully recovered.

Other patients with CFE have had less favorable outcomes. Chen and colleagues⁶ reported the case of a 31-year-old man who sustained closed femur and tibia fractures in an automobile collision and experienced an acute decline in neurologic status 1 hour after arrival in the emergency department. The patient was intubated, CFE was diagnosed on the basis of MRI findings, and the orthopedic injuries were treated with external fixation. After 2 weeks, the patient was discharged with persistent neurologic deficits and the need for long-term tube feeding. Walshe and colleagues¹⁷ reported the case of a 19-year-old woman who sustained multiple long-bone injuries and traumatic brain injury and showed fat emboli on MRI. The patient experienced brain herniation while in the intensive care unit and later was declared brain-dead. According to the literature, it is important to maintain high suspicion for FES and possible CFE in the setting of high-energy fracture but also to be aware that FES may develop even with nondisplaced fracture or with reaming of the intramedullary canal in elective total joint arthroplasty.¹⁸

 

Pathophysiology of Fat Embolism Syndrome

The pathophysiology of FES and specifically of CFE is not widely understood. Two main theories on the development of FES have been advanced.

The mechanical theory suggests that exposing intramedullary long-bone contents allows fat to mobilize into the bloodstream.¹⁹ This occurs in the setting of long-bone fracture and in canal preparation during joint replacement surgery. More fat extravasates into the venous system after femur fracture than after tibia fracture, which accounts for the higher risk for FES in femoral shaft fractures and the even higher risk in concomitant femur and tibia fractures.⁴ In addition to there being a risk of fat embolism from the fracture itself, placing the patient in traction or reaming the intramedullary canal may exacerbate this effect by increased extravasation of fat from the medullary canal. With extravasation of fatty bone marrow into the venous system, fat emboli are free to travel back to the lungs, where they can cause infarcts within the lung parenchyma.

In the mechanical theory, presence of PFO may allow fat globules to pass into the systemic circulation and cause end-organ emboli. In the event of cerebral emboli, neurologic symptoms may vary widely and may include diffuse encephalopathy and global deficits.²⁰ Dog studies have found a possible mechanism for CFE in the absence of PFO. One such study, which used femoral pressurization to replicate cemented femoral arthroplasty, found that many fat globules had traversed the lungs after release into bone marrow,²¹ supporting the theory that fat droplets can traverse the pulmonary system without sequestration in the lung parenchyma. Riding and colleagues²² reported finding pulmonary arteriovenous shunts, which are thought to allow CFE to occur in the absence of PFO. More studies are needed to determine the prevalence of shunts and their overall contribution to CFE development in patients with long-bone fracture.

The biochemical theory holds that bodily trauma induces the release of free fatty acids (FFAs) from the capillaries into the bloodstream.²³ This stress response is mediated by catecholamines, which activate the adenyl cyclase pathway, which activates lipase, which hydrolyzes stored triglycerides to FFAs and glycerol. The concentration of circulating FFA was increased in 9 of 10 patients in one study.²³ Increased FFAs in the bloodstream can accelerate local and end-organ clotting, leading to thrombocytopenia and endothelial injury. In addition, patients with hypercoagulable diseases are at higher risk for postoperative thromboembolism.²⁴ However, with a negative hypercoagulable work-up and with negative chest helical CT and EKG, which did not demonstrate PFO, the explanation for CFE in our patient may more likely reside with the arteriovenous shunt theory proposed by Riding and colleagues.²²

Diagnosis and Treatment

Proper care of orthopedic patients who potentially have FES/CFE involves prompt diagnosis, immediate symptomatic care, and early coordination with neurology and medical services to rule out other causes of symptoms. Obtaining advanced imaging to rule out other potential causes and to confirm the diagnosis is crucial. The patient in this case report did not exhibit any focal neurologic deficits, but emergent CT of the brain was indicated to rule out a hemorrhagic event. If a stroke secondary to FES is clinically suspected, MRI should be obtained as soon as possible. Multiple studies have found that the “starfield” pattern, which is best seen as multiple punctate hyperintensities on T2 imaging, is the typical radiographic manifestation of CFE.⁹ This applies to patients who are in the 24- to 72-hour window after long-bone fracture or fixation and who fit Gurd and Wilson¹ criteria or Lindeque^1,2criteria, or who exhibit a change in mental status but have a negative CT scan of the brain, as was the case with our patient. Once the diagnosis is made, treatment involves addressing the symptoms (Figure 4).

Hypoxia should be treated with supplementary oxygen; if acute respiratory distress syndrome develops, intubation and mechanical ventilation may be required. Patients with embolic phenomena causing CFE should receive aspirin for stroke prophylaxis and an antiepileptic for seizure prophylaxis. The best way to treat FES and CFE remains prevention with early operative fixation. If prevention fails, timely supportive care can help; a majority of patients who receive such care recover from neurologic and pulmonary sequelae (overall mortality rate, 10%).²⁵

Fat Embolism Syndrome in Reamed and Unreamed Nailing

Over the past several decades, the number of long bones fixed with intramedullary nails has increased significantly.²⁶ There is debate regarding whether use of reamed intramedullary nails increases the risk of fat emboli relative to use of unreamed nails, but multiple studies have found no significant difference.^26,27 Pulmonary shunting occurs in both reamed and unreamed nailing; neither technique has an advantage in terms of cardiopulmonary complications. In multiple studies, reamed nails have the advantage of improved healing rates.²⁷ A sheep study compared reamed and unreamed femoral nailing.²⁸ After nailing, sheep lungs were examined histologically for the presence of bone marrow fat embolism. The embolism rate was higher with unreamed nailing (10.25%) than with reamed nailing (6.66%). One large study of the adverse effects of reamed and unreamed nailing in 1226 patients with tibial shaft fracture found that those with open fractures had higher rates of a negative event (nonunion, infection, fasciotomy, hardware failure, need for dynamization) after reamed nailing.²⁹ Patients with closed fractures had fewer events after reamed nailing. The authors concluded there is a potential benefit in outcome with reamed intramedullary nailing in patients with closed tibial shaft fractures, but they did not comment on development of FES. In a study of the effect of subject position on intramedullary pressure and fat embolism release, dogs were positioned either supine or lateral for tibial and femoral reaming.³⁰ The authors measured various physiologic parameters, including cardiac output, pulmonary arterial wedge pressure, arterial and venous blood gas, and blood cell counts. There were no statistically significant differences in values between the 2 groups in any variable, indicating that position does not affect FES development in the orthopedic trauma setting.

 

Conclusion

FES and CFE are potential devastating sequelae of both long-bone fracture and long-bone instrumentation. It is important to recognize these entities in the acute setting and to consider them in the differential diagnosis of a trauma or postoperative patient who experiences sudden onset of altered mental status with or without dyspnea or a petechial rash. If CFE is suspected, early advanced imaging (including urgent MRI) should be obtained with rapid involvement of a multidisciplinary team that can optimize the chance for successful recovery of both neurologic and physical function. The best treatment, early prevention and diagnosis, maximizes care of symptoms. As is evidenced in this case report, rapid diagnosis and treatment often result in recovery from a majority of the symptoms of FES and CFE.

Am J Orthop. 2016;45(7):E515-E521. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Bone grafting is the main method of treating nonunions.¹ The multiple bone graft options available include autogenous bone grafts, allogenic bone grafts, and synthetic bone graft substitutes.^2,3 Autogenous bone graft has long been considered the gold standard, as it reduces the risk of infection and eliminates the risk of immune rejection associated with allograft; in addition, autograft has the optimal combination of osteogenic, osteoinductive, and osteoconductive properties.^2,4,5 Iliac crest bone graft (ICBG), though the most commonly used autogenous bone graft source, has been associated with infection, hematoma, poor cosmetic outcomes, hernia, neurovascular insults, and chronic persistent pain.^6,7 Intramedullary bone graft harvest performed with the Reamer/Irrigator/Aspirator (RIA) system (DePuy Synthes) is a novel technique that allows for simultaneous débridement and collection of bone graft, protects against thermal necrosis and extravasation of marrow contents, and maintains biomechanical strength for weight-bearing.^3,4,8,9 Furthermore, RIA aspirate is a rich source of autologous bone graft and provides equal or superior amounts of graft in comparison with ICBG.^5-7,10-12

In some cases, RIA is associated with the complication of host bone fracture.^4,6,7,11,12 In addition, introducing the reamer may contribute to pain at its entry site and may require violation of local soft-tissue attachments at the hip or knees.^4,7,13 In this study, we assessed the possibility of using a new RIA technique to eliminate these adverse effects. We hypothesized that distal femoral nonunions could be successfully treated with the RIA passed retrograde through the nonunion site. This technique may obviate the need for a secondary surgical site (required in traditional intramedullary bone graft harvest), minimize the potential entry-site tissue (eg, hip abductor) damage encountered with the antegrade technique, and yield harvested bone graft in quantities similar to those obtained with the standard technique.

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the medical records of all patients with a distal femur nonunion treated with autogenous bone grafting between 2009 and 2013. Identified patients had undergone a novel intramedullary harvest technique that involved passing an RIA retrograde through the nonunion site. Data (patient demographics, volume of graft obtained, perioperative complications, postoperative clinical course) were extracted from the medical records. Before data collection, all patients provided written informed consent for print and electronic publication of their case reports.

Technique

The patient was laid supine on a radiolucent table, and the affected extremity was prepared and draped free. A standard lateral incision previously used for the index procedure was employed. After implant removal, a rongeur, curette, and/or high-speed burr was used to débride the distal femur nonunion of all fibrous tissue. After mobilization and preparation of the distal femoral nonunion, varus angulation was accentuated with delivery of the proximal and distal segments of the nonunion into the wound (Figure A).

A ball-tipped guide wire was subsequently passed through the nonunion site for intramedullary bone graft harvest. The standard RIA technique was then applied to obtain the bone graft (Figure B).

Six patients underwent 7 separate procedures for distal femoral nonunion. Of these patients, 5 underwent retrograde RIA through the nonunion site, as described above; the sixth underwent antegrade RIA in the traditional fashion and was therefore excluded. One of the 5 patients underwent another bone grafting procedure after the initial retrograde RIA treatment through the nonunion site. Several outcomes were measured: ability to obtain graft, volume of graft obtained, perioperative complications, and feasibility of the procedure.

Mean age of the 5 patients was 40.4 years (range, 22-66 years). Mean reamer size was 13.4 mm (mode, 14 mm), producing an average bone graft volume of 33 mL. There were no intraoperative or postoperative fractures. In 1 case, the reamer shaft broke during insertion and was retrieved with no retained hardware; passage was made with a new reamer shaft. No patient experienced additional pain or discomfort, as there was no separate entry site for the RIA.

Discussion

Bone grafting for nonunion is one of the most commonly performed procedures in orthopedic trauma surgery. Use of an intramedullary harvest system has become increasingly popular relative to alternative techniques. The RIA system is associated with less donor-site pain and provides relatively more bone graft volume in comparison with ICBG harvest.^6,7,10,13 Conversely, intramedullary bone graft harvest may be associated with higher risk of host bone fractures, occurring either during surgery (technical error being the cause) or afterward (a result of patient noncompliance or overaggressive reaming).^6,7,11,12 Multiple methods of reducing the risk of iatrogenic fracture caused by technical error of eccentric reaming have been described, including appropriate guide wire placement aided by frequent use of fluoroscopy in 2 planes.⁴ Despite these potential complications and improved donor-site pain complaints in comparison with ICBG harvest, traditional RIA harvest is still associated with pain at the entry site.^4,7,13

 

In this study, we introduced a novel RIA technique for distal femur nonunion. This technique reduces the complications and adverse effects associated with RIA. It removes the added pain and discomfort associated with a separate entry site. As the reamer is introduced into the medullary canal through the femoral nonunion site, and proximal harvest is limited to the subtrochanteric region, the technique also avoids the complications associated with eccentric reaming of the distal and proximal femur, which may contribute to secondary fracture.^6,7,11,12Although the proposed technique is practical, it may present some technical difficulties. First, failed fixation hardware must be removed, and by necessity some stripping of soft tissues is required. These actions are unavoidable, as hardware revision is inherent in the treatment of nonunion. During the procedure, the focus should be on minimizing the insult to bony healing. The nonunion also needs to be completely mobilized to allow adequate angulation, guide wire passage, and sequential reaming. The dual vascular insult of intramedullary reaming combined with the soft-tissue débridement and detachment required for hardware removal and mobilization can be concerning for devascularization of the fracture fragment. However, animal studies have suggested reaming does not affect metaphyseal blood flow; it affects only diaphyseal bone.^6,14 The metaphyseal/diaphyseal location of these distal femur nonunions is thought to provide at least partial sparing from the endosteal injury that the RIA may cause. Another difficulty is that the angle of passage of the wire requires a relatively steeper curve to be able to pass beyond the medial distal femoral wall and proceed more proximally. Strong manipulation of the segment is required, which in 1 case caused the reamer shaft to break. This complication had minimal sequelae; the shaft was easily retrieved by withdrawing the ball-tipped guide wire. In addition, strong manipulation of the segment can lead to asymmetric medial reaming or fracture—an outcome easily avoided with a small bend in the distal tip of the guide wire and frequent use of fluoroscopy. In all cases in this series, we achieved proximal passage of the wire and the reamer.

Most RIA bone graft is harvested by reaming the medullary canal at the midshaft of the femur. Passing from the distal femoral nonunion precludes obtaining only a small source of potential distal femoral bone graft, though this metaphyseal bone typically is not used for fear of eccentric reaming and secondary fracture.^6,7,11,12 The amount of bone graft obtained from selected patients who undergo retrograde RIA passage through the nonunion site should be similar to the amount obtained with the traditional antegrade method. Our newly proposed technique provided an average bone graft volume of 33 mL, which compares favorably with that reported in the literature for the traditional RIA technique.^{1,5,6,13,15,16}

Conclusion

In distal femoral cases, retrograde passage of the RIA through the nonunion site is technically feasible and has reproducible yields of intramedullary bone graft. Adequate mobilization of the nonunion is a prerequisite for reamer harvest. However, this technique obviates the need for an additional entry point. Furthermore, the technique may limit the perioperative fracture risk previously seen with eccentric reaming of the distal and proximal femur using traditional intramedullary harvest.

Am J Orthop. 2016;45(7):E493-E496. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Bone grafting is the main method of treating nonunions.¹ The multiple bone graft options available include autogenous bone grafts, allogenic bone grafts, and synthetic bone graft substitutes.^2,3 Autogenous bone graft has long been considered the gold standard, as it reduces the risk of infection and eliminates the risk of immune rejection associated with allograft; in addition, autograft has the optimal combination of osteogenic, osteoinductive, and osteoconductive properties.^2,4,5 Iliac crest bone graft (ICBG), though the most commonly used autogenous bone graft source, has been associated with infection, hematoma, poor cosmetic outcomes, hernia, neurovascular insults, and chronic persistent pain.^6,7 Intramedullary bone graft harvest performed with the Reamer/Irrigator/Aspirator (RIA) system (DePuy Synthes) is a novel technique that allows for simultaneous débridement and collection of bone graft, protects against thermal necrosis and extravasation of marrow contents, and maintains biomechanical strength for weight-bearing.^3,4,8,9 Furthermore, RIA aspirate is a rich source of autologous bone graft and provides equal or superior amounts of graft in comparison with ICBG.^5-7,10-12

In some cases, RIA is associated with the complication of host bone fracture.^4,6,7,11,12 In addition, introducing the reamer may contribute to pain at its entry site and may require violation of local soft-tissue attachments at the hip or knees.^4,7,13 In this study, we assessed the possibility of using a new RIA technique to eliminate these adverse effects. We hypothesized that distal femoral nonunions could be successfully treated with the RIA passed retrograde through the nonunion site. This technique may obviate the need for a secondary surgical site (required in traditional intramedullary bone graft harvest), minimize the potential entry-site tissue (eg, hip abductor) damage encountered with the antegrade technique, and yield harvested bone graft in quantities similar to those obtained with the standard technique.

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the medical records of all patients with a distal femur nonunion treated with autogenous bone grafting between 2009 and 2013. Identified patients had undergone a novel intramedullary harvest technique that involved passing an RIA retrograde through the nonunion site. Data (patient demographics, volume of graft obtained, perioperative complications, postoperative clinical course) were extracted from the medical records. Before data collection, all patients provided written informed consent for print and electronic publication of their case reports.

Technique

The patient was laid supine on a radiolucent table, and the affected extremity was prepared and draped free. A standard lateral incision previously used for the index procedure was employed. After implant removal, a rongeur, curette, and/or high-speed burr was used to débride the distal femur nonunion of all fibrous tissue. After mobilization and preparation of the distal femoral nonunion, varus angulation was accentuated with delivery of the proximal and distal segments of the nonunion into the wound (Figure A).

A ball-tipped guide wire was subsequently passed through the nonunion site for intramedullary bone graft harvest. The standard RIA technique was then applied to obtain the bone graft (Figure B).

Six patients underwent 7 separate procedures for distal femoral nonunion. Of these patients, 5 underwent retrograde RIA through the nonunion site, as described above; the sixth underwent antegrade RIA in the traditional fashion and was therefore excluded. One of the 5 patients underwent another bone grafting procedure after the initial retrograde RIA treatment through the nonunion site. Several outcomes were measured: ability to obtain graft, volume of graft obtained, perioperative complications, and feasibility of the procedure.

Mean age of the 5 patients was 40.4 years (range, 22-66 years). Mean reamer size was 13.4 mm (mode, 14 mm), producing an average bone graft volume of 33 mL. There were no intraoperative or postoperative fractures. In 1 case, the reamer shaft broke during insertion and was retrieved with no retained hardware; passage was made with a new reamer shaft. No patient experienced additional pain or discomfort, as there was no separate entry site for the RIA.

Discussion

Bone grafting for nonunion is one of the most commonly performed procedures in orthopedic trauma surgery. Use of an intramedullary harvest system has become increasingly popular relative to alternative techniques. The RIA system is associated with less donor-site pain and provides relatively more bone graft volume in comparison with ICBG harvest.^6,7,10,13 Conversely, intramedullary bone graft harvest may be associated with higher risk of host bone fractures, occurring either during surgery (technical error being the cause) or afterward (a result of patient noncompliance or overaggressive reaming).^6,7,11,12 Multiple methods of reducing the risk of iatrogenic fracture caused by technical error of eccentric reaming have been described, including appropriate guide wire placement aided by frequent use of fluoroscopy in 2 planes.⁴ Despite these potential complications and improved donor-site pain complaints in comparison with ICBG harvest, traditional RIA harvest is still associated with pain at the entry site.^4,7,13

 

In this study, we introduced a novel RIA technique for distal femur nonunion. This technique reduces the complications and adverse effects associated with RIA. It removes the added pain and discomfort associated with a separate entry site. As the reamer is introduced into the medullary canal through the femoral nonunion site, and proximal harvest is limited to the subtrochanteric region, the technique also avoids the complications associated with eccentric reaming of the distal and proximal femur, which may contribute to secondary fracture.^6,7,11,12Although the proposed technique is practical, it may present some technical difficulties. First, failed fixation hardware must be removed, and by necessity some stripping of soft tissues is required. These actions are unavoidable, as hardware revision is inherent in the treatment of nonunion. During the procedure, the focus should be on minimizing the insult to bony healing. The nonunion also needs to be completely mobilized to allow adequate angulation, guide wire passage, and sequential reaming. The dual vascular insult of intramedullary reaming combined with the soft-tissue débridement and detachment required for hardware removal and mobilization can be concerning for devascularization of the fracture fragment. However, animal studies have suggested reaming does not affect metaphyseal blood flow; it affects only diaphyseal bone.^6,14 The metaphyseal/diaphyseal location of these distal femur nonunions is thought to provide at least partial sparing from the endosteal injury that the RIA may cause. Another difficulty is that the angle of passage of the wire requires a relatively steeper curve to be able to pass beyond the medial distal femoral wall and proceed more proximally. Strong manipulation of the segment is required, which in 1 case caused the reamer shaft to break. This complication had minimal sequelae; the shaft was easily retrieved by withdrawing the ball-tipped guide wire. In addition, strong manipulation of the segment can lead to asymmetric medial reaming or fracture—an outcome easily avoided with a small bend in the distal tip of the guide wire and frequent use of fluoroscopy. In all cases in this series, we achieved proximal passage of the wire and the reamer.

Most RIA bone graft is harvested by reaming the medullary canal at the midshaft of the femur. Passing from the distal femoral nonunion precludes obtaining only a small source of potential distal femoral bone graft, though this metaphyseal bone typically is not used for fear of eccentric reaming and secondary fracture.^6,7,11,12 The amount of bone graft obtained from selected patients who undergo retrograde RIA passage through the nonunion site should be similar to the amount obtained with the traditional antegrade method. Our newly proposed technique provided an average bone graft volume of 33 mL, which compares favorably with that reported in the literature for the traditional RIA technique.^{1,5,6,13,15,16}

Conclusion

In distal femoral cases, retrograde passage of the RIA through the nonunion site is technically feasible and has reproducible yields of intramedullary bone graft. Adequate mobilization of the nonunion is a prerequisite for reamer harvest. However, this technique obviates the need for an additional entry point. Furthermore, the technique may limit the perioperative fracture risk previously seen with eccentric reaming of the distal and proximal femur using traditional intramedullary harvest.

Am J Orthop. 2016;45(7):E493-E496. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.

Bone grafting is the main method of treating nonunions.¹ The multiple bone graft options available include autogenous bone grafts, allogenic bone grafts, and synthetic bone graft substitutes.^2,3 Autogenous bone graft has long been considered the gold standard, as it reduces the risk of infection and eliminates the risk of immune rejection associated with allograft; in addition, autograft has the optimal combination of osteogenic, osteoinductive, and osteoconductive properties.^2,4,5 Iliac crest bone graft (ICBG), though the most commonly used autogenous bone graft source, has been associated with infection, hematoma, poor cosmetic outcomes, hernia, neurovascular insults, and chronic persistent pain.^6,7 Intramedullary bone graft harvest performed with the Reamer/Irrigator/Aspirator (RIA) system (DePuy Synthes) is a novel technique that allows for simultaneous débridement and collection of bone graft, protects against thermal necrosis and extravasation of marrow contents, and maintains biomechanical strength for weight-bearing.^3,4,8,9 Furthermore, RIA aspirate is a rich source of autologous bone graft and provides equal or superior amounts of graft in comparison with ICBG.^5-7,10-12

In some cases, RIA is associated with the complication of host bone fracture.^4,6,7,11,12 In addition, introducing the reamer may contribute to pain at its entry site and may require violation of local soft-tissue attachments at the hip or knees.^4,7,13 In this study, we assessed the possibility of using a new RIA technique to eliminate these adverse effects. We hypothesized that distal femoral nonunions could be successfully treated with the RIA passed retrograde through the nonunion site. This technique may obviate the need for a secondary surgical site (required in traditional intramedullary bone graft harvest), minimize the potential entry-site tissue (eg, hip abductor) damage encountered with the antegrade technique, and yield harvested bone graft in quantities similar to those obtained with the standard technique.

After obtaining Institutional Review Board approval for this study, we retrospectively reviewed the medical records of all patients with a distal femur nonunion treated with autogenous bone grafting between 2009 and 2013. Identified patients had undergone a novel intramedullary harvest technique that involved passing an RIA retrograde through the nonunion site. Data (patient demographics, volume of graft obtained, perioperative complications, postoperative clinical course) were extracted from the medical records. Before data collection, all patients provided written informed consent for print and electronic publication of their case reports.

Technique

The patient was laid supine on a radiolucent table, and the affected extremity was prepared and draped free. A standard lateral incision previously used for the index procedure was employed. After implant removal, a rongeur, curette, and/or high-speed burr was used to débride the distal femur nonunion of all fibrous tissue. After mobilization and preparation of the distal femoral nonunion, varus angulation was accentuated with delivery of the proximal and distal segments of the nonunion into the wound (Figure A).

A ball-tipped guide wire was subsequently passed through the nonunion site for intramedullary bone graft harvest. The standard RIA technique was then applied to obtain the bone graft (Figure B).

Six patients underwent 7 separate procedures for distal femoral nonunion. Of these patients, 5 underwent retrograde RIA through the nonunion site, as described above; the sixth underwent antegrade RIA in the traditional fashion and was therefore excluded. One of the 5 patients underwent another bone grafting procedure after the initial retrograde RIA treatment through the nonunion site. Several outcomes were measured: ability to obtain graft, volume of graft obtained, perioperative complications, and feasibility of the procedure.

Mean age of the 5 patients was 40.4 years (range, 22-66 years). Mean reamer size was 13.4 mm (mode, 14 mm), producing an average bone graft volume of 33 mL. There were no intraoperative or postoperative fractures. In 1 case, the reamer shaft broke during insertion and was retrieved with no retained hardware; passage was made with a new reamer shaft. No patient experienced additional pain or discomfort, as there was no separate entry site for the RIA.

Discussion

Bone grafting for nonunion is one of the most commonly performed procedures in orthopedic trauma surgery. Use of an intramedullary harvest system has become increasingly popular relative to alternative techniques. The RIA system is associated with less donor-site pain and provides relatively more bone graft volume in comparison with ICBG harvest.^6,7,10,13 Conversely, intramedullary bone graft harvest may be associated with higher risk of host bone fractures, occurring either during surgery (technical error being the cause) or afterward (a result of patient noncompliance or overaggressive reaming).^6,7,11,12 Multiple methods of reducing the risk of iatrogenic fracture caused by technical error of eccentric reaming have been described, including appropriate guide wire placement aided by frequent use of fluoroscopy in 2 planes.⁴ Despite these potential complications and improved donor-site pain complaints in comparison with ICBG harvest, traditional RIA harvest is still associated with pain at the entry site.^4,7,13

 

In this study, we introduced a novel RIA technique for distal femur nonunion. This technique reduces the complications and adverse effects associated with RIA. It removes the added pain and discomfort associated with a separate entry site. As the reamer is introduced into the medullary canal through the femoral nonunion site, and proximal harvest is limited to the subtrochanteric region, the technique also avoids the complications associated with eccentric reaming of the distal and proximal femur, which may contribute to secondary fracture.^6,7,11,12Although the proposed technique is practical, it may present some technical difficulties. First, failed fixation hardware must be removed, and by necessity some stripping of soft tissues is required. These actions are unavoidable, as hardware revision is inherent in the treatment of nonunion. During the procedure, the focus should be on minimizing the insult to bony healing. The nonunion also needs to be completely mobilized to allow adequate angulation, guide wire passage, and sequential reaming. The dual vascular insult of intramedullary reaming combined with the soft-tissue débridement and detachment required for hardware removal and mobilization can be concerning for devascularization of the fracture fragment. However, animal studies have suggested reaming does not affect metaphyseal blood flow; it affects only diaphyseal bone.^6,14 The metaphyseal/diaphyseal location of these distal femur nonunions is thought to provide at least partial sparing from the endosteal injury that the RIA may cause. Another difficulty is that the angle of passage of the wire requires a relatively steeper curve to be able to pass beyond the medial distal femoral wall and proceed more proximally. Strong manipulation of the segment is required, which in 1 case caused the reamer shaft to break. This complication had minimal sequelae; the shaft was easily retrieved by withdrawing the ball-tipped guide wire. In addition, strong manipulation of the segment can lead to asymmetric medial reaming or fracture—an outcome easily avoided with a small bend in the distal tip of the guide wire and frequent use of fluoroscopy. In all cases in this series, we achieved proximal passage of the wire and the reamer.

Most RIA bone graft is harvested by reaming the medullary canal at the midshaft of the femur. Passing from the distal femoral nonunion precludes obtaining only a small source of potential distal femoral bone graft, though this metaphyseal bone typically is not used for fear of eccentric reaming and secondary fracture.^6,7,11,12 The amount of bone graft obtained from selected patients who undergo retrograde RIA passage through the nonunion site should be similar to the amount obtained with the traditional antegrade method. Our newly proposed technique provided an average bone graft volume of 33 mL, which compares favorably with that reported in the literature for the traditional RIA technique.^{1,5,6,13,15,16}

Conclusion

In distal femoral cases, retrograde passage of the RIA through the nonunion site is technically feasible and has reproducible yields of intramedullary bone graft. Adequate mobilization of the nonunion is a prerequisite for reamer harvest. However, this technique obviates the need for an additional entry point. Furthermore, the technique may limit the perioperative fracture risk previously seen with eccentric reaming of the distal and proximal femur using traditional intramedullary harvest.

Am J Orthop. 2016;45(7):E493-E496. Copyright Frontline Medical Communications Inc. 2016. All rights reserved.