The article by Dr. Alison Colantino et al in this issue on when to resume anticoagulation after a hemorrhagic event is relevant to the discussion of clinical decision-making that I started here last month. My thoughts then were prompted by a commentary by Dr. Vinay Prasad on incorporating appropriate study outcomes in clinical decision-making (Cleve Clin J Med 2015; 82:146–150).

In the clinic or hospital, we make many decisions without being able to cite specific applicable clinical studies. I base some decisions on my overall impression from the literature (including formal trials), some on general recall of a specific study (which I hopefully either find time to review afterwards, or ask one of our trainees to read and discuss with our team the next day), and others on my knowledge of clinical guidelines or clearly accepted practice. Most clinical decisions are made without any directly applicable data from available clinical studies. This is the “art” of medicine.

Should this art make its way into our clinical journals, and if so, how extensively, and how should it be framed? It is relatively easy when we are talking about the science of clinical practice. Journals receive the (hopefully complete) data, get peer reviews to improve the paper, and publish it with the authors’ opinions presented in the discussion section. Then, dialogue ensues in the published literature, in educational lectures, and in blogs posted on the Internet. But where does the art go? Does it belong in our traditionally conservative textbooks or newer go-to online resources, which emphasize the need for authors to provide updated specific references for their treatment recommendations? We believe that after our best efforts at peer review it is appropriate to publish it in the CCJM because hopefully it can provide additional perspective on how we deliver care to our patients.

In the arena of new therapies, regulatory approval requires hard data documenting efficacy and safety. And that often leaves me without approved or sometimes even “proven effective” therapies to use when treating patients with relatively uncommon conditions, such as refractory uveitis with threatened visual loss or idiopathic aortitis. Yet I still need to treat the patient.

Another aspect of the art of medicine relates to how best to use therapies that have been approved. We have had antibiotics for many decades, but data are still being generated on how long to treat specific infections, and relatively few scenarios have been studied. Huge media coverage and (mostly) appropriate hype were generated over the need to treat patients with postmenopausal osteoporosis as diagnosed by dual-energy x-ray absorptiometry. But even after evidence emerged regarding atypical femoral fractures in patients receiving long-term bisphosphonate therapy, the question of how long treatment should continue remains more art than science.

The field of anticoagulation has seen many recent advances. We have new heparins, new target-specific oral anticoagulants, and a lot of new science on the natural history of some thrombotic disorders and the efficacy and safety of these new agents. But how long to treat specific thrombotic conditions, which agent to use, how intense the anticoagulation needs to be, when to use bridging therapy, and, as discussed by Dr. Colantino et al, when to resume anticoagulation after a hemorrhagic event mostly remain part of the art of medicine.

I highlight the Colantino paper in the context of both clinical and editorial decision-making because it is an example of experienced clinical authors discussing their solutions to thorny clinical scenarios we often face with inadequate data. While some journals avoid this approach, we embrace the opportunity to provide thoughtful expert opinions to our readers. We push authors from the start of the editorial process and through aggressive peer review to provide evidence to support their practice recommendations when appropriate. But we also encourage them to make recommendations and describe their own decision-making process in situations that may not be fully described in the literature.

Most of our readers do not have ready access to consultants who have had years of experience within multidisciplinary teams at referral institutions regularly managing patients with permutations of these complex clinical problems. Though generic consultation advice must be evaluated within the context of the specific patient, we hope that by framing the clinical issues with relevant clinical science the opinions of experienced authors will be of use in guiding your (and my) approach to similar clinical scenarios.

If you think we are not striking the right balance between the science and the art of medical practice, please let me know.

The article by Dr. Alison Colantino et al in this issue on when to resume anticoagulation after a hemorrhagic event is relevant to the discussion of clinical decision-making that I started here last month. My thoughts then were prompted by a commentary by Dr. Vinay Prasad on incorporating appropriate study outcomes in clinical decision-making (Cleve Clin J Med 2015; 82:146–150).

In the clinic or hospital, we make many decisions without being able to cite specific applicable clinical studies. I base some decisions on my overall impression from the literature (including formal trials), some on general recall of a specific study (which I hopefully either find time to review afterwards, or ask one of our trainees to read and discuss with our team the next day), and others on my knowledge of clinical guidelines or clearly accepted practice. Most clinical decisions are made without any directly applicable data from available clinical studies. This is the “art” of medicine.

Should this art make its way into our clinical journals, and if so, how extensively, and how should it be framed? It is relatively easy when we are talking about the science of clinical practice. Journals receive the (hopefully complete) data, get peer reviews to improve the paper, and publish it with the authors’ opinions presented in the discussion section. Then, dialogue ensues in the published literature, in educational lectures, and in blogs posted on the Internet. But where does the art go? Does it belong in our traditionally conservative textbooks or newer go-to online resources, which emphasize the need for authors to provide updated specific references for their treatment recommendations? We believe that after our best efforts at peer review it is appropriate to publish it in the CCJM because hopefully it can provide additional perspective on how we deliver care to our patients.

In the arena of new therapies, regulatory approval requires hard data documenting efficacy and safety. And that often leaves me without approved or sometimes even “proven effective” therapies to use when treating patients with relatively uncommon conditions, such as refractory uveitis with threatened visual loss or idiopathic aortitis. Yet I still need to treat the patient.

Another aspect of the art of medicine relates to how best to use therapies that have been approved. We have had antibiotics for many decades, but data are still being generated on how long to treat specific infections, and relatively few scenarios have been studied. Huge media coverage and (mostly) appropriate hype were generated over the need to treat patients with postmenopausal osteoporosis as diagnosed by dual-energy x-ray absorptiometry. But even after evidence emerged regarding atypical femoral fractures in patients receiving long-term bisphosphonate therapy, the question of how long treatment should continue remains more art than science.

The field of anticoagulation has seen many recent advances. We have new heparins, new target-specific oral anticoagulants, and a lot of new science on the natural history of some thrombotic disorders and the efficacy and safety of these new agents. But how long to treat specific thrombotic conditions, which agent to use, how intense the anticoagulation needs to be, when to use bridging therapy, and, as discussed by Dr. Colantino et al, when to resume anticoagulation after a hemorrhagic event mostly remain part of the art of medicine.

I highlight the Colantino paper in the context of both clinical and editorial decision-making because it is an example of experienced clinical authors discussing their solutions to thorny clinical scenarios we often face with inadequate data. While some journals avoid this approach, we embrace the opportunity to provide thoughtful expert opinions to our readers. We push authors from the start of the editorial process and through aggressive peer review to provide evidence to support their practice recommendations when appropriate. But we also encourage them to make recommendations and describe their own decision-making process in situations that may not be fully described in the literature.

Most of our readers do not have ready access to consultants who have had years of experience within multidisciplinary teams at referral institutions regularly managing patients with permutations of these complex clinical problems. Though generic consultation advice must be evaluated within the context of the specific patient, we hope that by framing the clinical issues with relevant clinical science the opinions of experienced authors will be of use in guiding your (and my) approach to similar clinical scenarios.

If you think we are not striking the right balance between the science and the art of medical practice, please let me know.

The article by Dr. Alison Colantino et al in this issue on when to resume anticoagulation after a hemorrhagic event is relevant to the discussion of clinical decision-making that I started here last month. My thoughts then were prompted by a commentary by Dr. Vinay Prasad on incorporating appropriate study outcomes in clinical decision-making (Cleve Clin J Med 2015; 82:146–150).

In the clinic or hospital, we make many decisions without being able to cite specific applicable clinical studies. I base some decisions on my overall impression from the literature (including formal trials), some on general recall of a specific study (which I hopefully either find time to review afterwards, or ask one of our trainees to read and discuss with our team the next day), and others on my knowledge of clinical guidelines or clearly accepted practice. Most clinical decisions are made without any directly applicable data from available clinical studies. This is the “art” of medicine.

Should this art make its way into our clinical journals, and if so, how extensively, and how should it be framed? It is relatively easy when we are talking about the science of clinical practice. Journals receive the (hopefully complete) data, get peer reviews to improve the paper, and publish it with the authors’ opinions presented in the discussion section. Then, dialogue ensues in the published literature, in educational lectures, and in blogs posted on the Internet. But where does the art go? Does it belong in our traditionally conservative textbooks or newer go-to online resources, which emphasize the need for authors to provide updated specific references for their treatment recommendations? We believe that after our best efforts at peer review it is appropriate to publish it in the CCJM because hopefully it can provide additional perspective on how we deliver care to our patients.

In the arena of new therapies, regulatory approval requires hard data documenting efficacy and safety. And that often leaves me without approved or sometimes even “proven effective” therapies to use when treating patients with relatively uncommon conditions, such as refractory uveitis with threatened visual loss or idiopathic aortitis. Yet I still need to treat the patient.

Another aspect of the art of medicine relates to how best to use therapies that have been approved. We have had antibiotics for many decades, but data are still being generated on how long to treat specific infections, and relatively few scenarios have been studied. Huge media coverage and (mostly) appropriate hype were generated over the need to treat patients with postmenopausal osteoporosis as diagnosed by dual-energy x-ray absorptiometry. But even after evidence emerged regarding atypical femoral fractures in patients receiving long-term bisphosphonate therapy, the question of how long treatment should continue remains more art than science.

The field of anticoagulation has seen many recent advances. We have new heparins, new target-specific oral anticoagulants, and a lot of new science on the natural history of some thrombotic disorders and the efficacy and safety of these new agents. But how long to treat specific thrombotic conditions, which agent to use, how intense the anticoagulation needs to be, when to use bridging therapy, and, as discussed by Dr. Colantino et al, when to resume anticoagulation after a hemorrhagic event mostly remain part of the art of medicine.

I highlight the Colantino paper in the context of both clinical and editorial decision-making because it is an example of experienced clinical authors discussing their solutions to thorny clinical scenarios we often face with inadequate data. While some journals avoid this approach, we embrace the opportunity to provide thoughtful expert opinions to our readers. We push authors from the start of the editorial process and through aggressive peer review to provide evidence to support their practice recommendations when appropriate. But we also encourage them to make recommendations and describe their own decision-making process in situations that may not be fully described in the literature.

Most of our readers do not have ready access to consultants who have had years of experience within multidisciplinary teams at referral institutions regularly managing patients with permutations of these complex clinical problems. Though generic consultation advice must be evaluated within the context of the specific patient, we hope that by framing the clinical issues with relevant clinical science the opinions of experienced authors will be of use in guiding your (and my) approach to similar clinical scenarios.

If you think we are not striking the right balance between the science and the art of medical practice, please let me know.

If a patient receiving anticoagulant therapy suffers a bleeding event, the patient and physician must decide whether and how soon to restart the therapy, and with what agent.

Foremost on our minds tends to be the risk of another hemorrhage. Subtler to appreciate immediately after an event is the continued risk of thrombosis, often from the same medical condition that prompted anticoagulation therapy in the first place (Table 1).

Complicating the decision, there may be a rebound effect: some thrombotic events such as pulmonary embolism and atrial fibrillation-related stroke may be more likely to occur in the first weeks after stopping warfarin than during similar intervals in patients who have not been taking it.^1–3 The same thing may happen with the newer, target-specific oral anticoagulants.^4–6

Although we have evidence-based guidelines for initiating and managing anticoagulant therapy, ample data on adverse events, and protocols for reversing anticoagulation if bleeding occurs, we do not have clear guidelines on restarting anticoagulation after a hemorrhagic event.

In this article, we outline a practical framework for approaching this clinical dilemma. Used in conjunction with consideration of a patient’s values and preferences as well as input from experts, this framework can help clinicians guide their patients through this challenging clinical decision. It consists of five questions:

• Why is the patient on anticoagulation, and what is the risk of thromboembolism without it?
• What was the clinical impact of the hemorrhage, and what is the risk of rebleeding if anticoagulation is resumed?
• What additional patient factors should be taken into consideration?
• How long should we wait before restarting anticoagulation?
• Would a newer drug be a better choice?

BLEEDING OCCURS IN 2% TO 3% OF PATIENTS PER YEAR

Most of our information on anticoagulation is about vitamin K antagonists—principally warfarin, in use since the 1950s. Among patients taking warfarin outside of clinical trials, the risk of major bleeding is estimated at 2% to 3% per year.⁷

However, the target-specific oral anticoagulants rivaroxaban (Xarelto), apixaban (Eliquis),  dabigatran (Pradaxa) and edoxaban (Savaysa) are being used more and more, and we include them in our discussion insofar as we have information on them. The rates of bleeding with these new drugs in clinical trials have been comparable to or lower than those with warfarin.⁸ Postmarketing surveillance is under way.

WHY IS THE PATIENT ON ANTICOAGULATION? WHAT IS THE RISK WITHOUT IT?

Common, evidence-based indications for anticoagulation are to prevent complications in patients with venous thromboembolism and to prevent stroke in patients with atrial fibrillation or a mechanical heart valve. Other uses, such as in heart failure and its sequelae, pulmonary hypertension, and splanchnic or hepatic vein thrombosis, have less robust evidence to support them.

When anticoagulation-related bleeding occurs, it is essential to review why the patient is taking the drug and the risk of thromboembolism without it. Some indications pose a higher risk of thromboembolism than others and so argue more strongly for continuing the treatment.

Douketis et al⁹ developed a risk-stratification scheme for perioperative thromboembolism. We have modified it by adding the CHA₂DS₂-VASc score (Table 2),^9–11 and believe it can be used more widely.

High-risk indications

Conditions that pose a high risk of thrombosis almost always require restarting anticoagulation. Here, the most appropriate question nearly always is not if anticoagulation should be restarted, but when. Examples:

• A mechanical mitral valve
• Antiphospholipid antibody syndrome with recurrent thromboembolic events.

Lower-risk indications

Lower-risk indications allow more leeway in determining if anticoagulation should be resumed. The most straightforward cases fall well within established guidelines. Examples:

• Atrial fibrillation and a CHA₂DS₂-VASc score of 1. The 2014 guidelines from the American College of Cardiology, American Heart Association, and Heart Rhythm Society¹⁰ suggest that patients with nonvalvular atrial fibrillation and a CHA₂DS₂-VASc score of 1 have three options: an oral anticoagulant, aspirin, and no antithrombotic therapy. If such a patient on anticoagulant therapy subsequently experiences a major gastrointestinal hemorrhage requiring transfusion and intensive care and no definitively treatable source of bleeding is found on endoscopy, one can argue that the risks of continued anticoagulation (recurrent bleeding) now exceed the benefits and that the patient would be better served by aspirin or even no antithrombotic therapy.

• After 6 months of anticoagulation for unprovoked deep vein thrombosis. Several studies showed that aspirin reduced the risk of recurrent venous thromboembolism in patients who completed an initial 6-month course of anticoagulation.^12–15 Though these studies did not specifically compare aspirin with warfarin or target-specific oral anticoagulants in preventing recurrent venous thromboembolism after a hemorrhage, it is reasonable to extrapolate their results to this situation.

If the risk of recurrent hemorrhage on anticoagulation is considered to be too great, then aspirin is an alternative to no anticoagulation, as it reduces the risk of recurrent venous thromboembolism.¹⁶ However, we advise caution if the bleeding lesion may be specifically exacerbated by aspirin, particularly upper gastrointestinal ulcers.

Moderate-risk indications

• After a partial course of anticoagulation for provoked venous thromboembolism. Suppose a patient in the 10th week of a planned 12-week course of anticoagulation for a surgically provoked, first deep vein thrombosis presents with abdominal pain and is found to have a retroperitoneal hematoma. In light of the risk of recurrent bleeding vs the benefit of resuming anticoagulation for the limited remaining period, her 12-week treatment course can reasonably be shortened to 10 weeks.

The risk of recurrent venous thromboembolism when a patient is off anticoagulation decreases with time from the initial event. The highest risk, estimated at 0.3% to 1.3% per day, is in the first 4 weeks, falling to 0.03% to 0.2% per day in weeks 5 through 12, and 0.05% per day thereafter.^17–20

The risk of recurrent venous thromboembolism is greatest immediately after the event and decreases over time

Additionally, a pooled analysis of seven randomized trials suggests that patients with isolated, distal deep vein thrombosis provoked by a temporary risk factor did not have a high risk of recurrence after being treated for 4 to 6 weeks.²¹ These analyses are based on vitamin K antagonists, though it seems reasonable to extrapolate this information to the target-specific oral anticoagulants.

More challenging are situations in which the evidence supporting the initial or continued need for anticoagulation is less robust, such as in heart failure, pulmonary hypertension, or splanchnic and hepatic vein thrombosis. In these cases, the lack of strong evidence supporting the use of anticoagulation should make us hesitate to resume it after bleeding.

WHAT WAS THE CLINICAL IMPACT? WHAT IS THE RISK OF REBLEEDING?

Different groups have defined major and minor bleeding in different ways.^22,23 Several have proposed criteria to standardize how bleeding events (on warfarin and otherwise) are classified,^23–25 but the definitions differ.

Specifically, all agree that a “major” bleeding event is one that is fatal, involves bleeding into a major organ, or leads to a substantial decline in hemoglobin level. However, the Thrombolysis in Myocardial Infarction trials use a decline of more than 5 g/dL in their definition,^23,25 while the International Society on Thrombosis and Haemostasis uses 2 g/dL.²⁴

Here, we review the clinical impact of the most common sources of anticoagulation-related hemorrhage—gastrointestinal, soft tissue, and urinary tract²⁶—as well as intracerebral hemorrhage, a less common but more uniformly devastating event.²⁷

Clinical impact of gastrointestinal hemorrhage

Each year, about 4.5% of patients taking warfarin have a gastrointestinal hemorrhage, though not all of these events are major.²⁸ Evolving data suggest that the newer agents (particularly dabigatran, rivaroxaban, and edoxaban) pose a higher risk of gastrointestinal bleeding than warfarin.²⁹ Patients may need plasma and blood transfusions and intravenous phytonadione, all of which carry risks, albeit small.

Frequently, endoscopy is needed to find the source of bleeding and to control it. If this does not work, angiographic intervention to infuse vasoconstrictors or embolic coils into the culprit artery may be required, and some patients need surgery. Each intervention carries its own risk.

Clinical impact of soft-tissue hemorrhage

Soft-tissue hemorrhage accounts for more than 20% of warfarin-related bleeding events²⁶; as yet, we know of no data on the rate with the new drugs. Soft-tissue hemorrhage is often localized to the large muscles of the retroperitoneum and legs. Though retroperitoneal hemorrhage accounts for a relatively small portion of soft-tissue hemorrhages, it is associated with high rates of morbidity and death and will therefore be our focus.²⁶

Some indications for anticoagulation pose a higher risk of thromboembolism than others

Much of the clinical impact of retroperitoneal hemorrhage is from a mass effect that causes abdominal compartment syndrome, hydroureter, ileus, abscess formation, and acute and chronic pain. At least 20% of cases are associated with femoral neuropathy. It can also lead to deep vein thrombosis from venous compression, coupled with hypercoagulability in response to bleeding. Brisk bleeding can lead to shock and death, and the mortality rate in retroperitoneal hemorrhage is estimated at 20% or higher.³⁰

In many cases, the retroperitoneal hemorrhage will self-tamponade and the blood will be reabsorbed once the bleeding has stopped, but uncontrolled bleeding may require surgical or angiographic intervention.³⁰

Clinical impact of urinary tract hemorrhage

Gross or microscopic hematuria can be found in an estimated 2% to 24% of patients taking warfarin^31–33; data are lacking for the target-specific oral anticoagulants. Interventions required to manage urinary tract bleeding include bladder irrigation and, less often, transfusion.³¹ Since a significant number of cases of hematuria are due to neoplastic disease,³² a diagnostic workup with radiographic imaging of the upper tract and cystoscopy of the lower tract is usually required.³¹ While life-threatening hemorrhage is uncommon, complications such as transient urinary obstruction from clots may occur.

Clinical impact of intracranial hemorrhage

Intracranial hemorrhage is the most feared and deadly of the bleeding complications of anticoagulation. The incidence in patients on warfarin is estimated at 2% to 3% per year, which is markedly higher than the estimated incidence of 25 per 100,000 person-years in the general population.³⁴ Emerging data indicate that the newer drugs are also associated with a risk of intracranial hemorrhage, though the risk is about half that with vitamin K antagonists.³⁵ Intracranial hemorrhage leads to death or disability in 76% of cases, compared with 3% of cases of bleeding from the gastrointestinal or urinary tract.²⁷

Regardless of the source of bleeding, hospitalization is likely to be required and may be  prolonged, with attendant risks of nosocomial harms such as infection.

Risk of rebleeding

Given the scope and severity of anticoagulation-related bleeding, there is strong interest in predicting and preventing it. By some estimates, the incidence of recurrent bleeding after resuming vitamin K antagonists is 8% to 13%.²² Although there are several indices for predicting the risk of major bleeding when starting anticoagulation, there are currently no validated tools to estimate a patient’s risk of rebleeding.³⁶

The patient factor that most consistently predicts major bleeding is a history of bleeding, particularly from the gastrointestinal tract. Finding and controlling the source of bleeding is important.^26,37 For example, a patient with gross hematuria who is found on cystoscopy to have a urothelial papilloma is unlikely to have rebleeding if the tumor is successfully resected and serial follow-up shows no regrowth. In contrast, consider a patient with a major gastrointestinal hemorrhage, the source of which remains elusive after upper, lower, and capsule endoscopy or, alternatively, is suspected to be from one of multiple angiodysplastic lesions. Without definitive source management, this patient faces a high risk of rebleeding.

With or without anticoagulation, after a first intracranial hemorrhage the risk of another one is estimated at 2% to 4% per year.³⁴ An observational study found a recurrence rate of 7.5% when vitamin K antagonist therapy was started after an intracranial hemorrhage (though not all patients were on a vitamin K antagonist at the time of the first hemorrhage).³⁸

Evolving data suggest the newer oral agents pose a higher risk of GI bleeding

Patients with lobar hemorrhage and those with suspected cerebral amyloid angiopathy may be at particularly high risk if anticoagulation is resumed. Conversely, initial events attributed to uncontrolled hypertension that subsequently can be well controlled may portend a lower risk of rebleeding.³⁴ For other types of intracranial hemorrhage, recurrence rates can be even higher. Irrespective of anticoagulation, one prospective study estimated the crude annual rebleeding rate with untreated arteriovenous malformations to be 7%.³⁹ In chronic subdural hematoma, the recurrence rate after initial drainage has been estimated at 9.2% to 26.5%, with use of anticoagulants (in this case, vitamin K antagonists) being an independent predictor of recurrence.⁴⁰

WHAT OTHER PATIENT FACTORS NEED CONSIDERATION?

Target INR on warfarin

An important factor influencing the risk of bleeding with warfarin is the intensity of this therapy.³⁷ A meta-analysis⁴¹ found that the risks of major hemorrhage and thromboembolism are minimized if the goal international normalized ratio (INR) is 2.0 to 3.0. When considering resuming anticoagulation after bleeding, make sure the therapeutic target is appropriate.³⁷

Table 3 summarizes recommended therapeutic ranges for frequently encountered indications for warfarin.^36,42,43

INR at time of the event and challenges in controlling it

The decision to resume anticoagulation in patients who bled while using warfarin must take into account the actual INR at the time of the event.

For example, consider a patient whose INR values are consistently in the therapeutic range.  While on vacation, he receives ciprofloxacin for acute prostatitis from an urgent care team, and no adjustment to INR monitoring or warfarin dose is made. Several days later, he presents with lower gastrointestinal bleeding. His INR is 8, and colonoscopy reveals diverticulosis with a bleeding vessel, responsive to endoscopic therapy. After controlling the source of bleeding and reinforcing the need to always review new medications for potential interactions with anticoagulation, it is reasonable to expect that he once again will be able to keep his INR in the therapeutic range.

A patient on anticoagulation for the same indication but who has a history of repeated supratherapeutic levels, poor adherence, or poor access to INR monitoring poses very different concerns about resuming anticoagulation (as well as which agent to use, as we discuss below).

Of note, a high INR alone does not explain bleeding. It is estimated that a workup for gastrointestinal bleeding and gross hematuria uncovers previously undetected lesions in approximately one-third of cases involving warfarin.²⁶ A similar malignancy-unmasking effect is now recognized in patients using the target-specific oral agents who experience gastrointestinal bleeding.⁴⁴ Accordingly, we recommend a comprehensive source evaluation for any anticoagulation-related hemorrhage.

Comorbid conditions

Comorbid conditions associated with bleeding include cancer, end-stage renal disease, liver disease, arterial hypertension, prior stroke, and alcohol abuse.^37,45 Gait instability, regardless of cause, may also increase the risk of trauma-related hemorrhage, but some have estimated that a patient would need to fall multiple times per week to contraindicate anticoagulation on the basis of falls alone.⁴⁶

Concurrent medications

Concomitant therapies, including antiplatelet drugs and nonsteroidal anti-inflammatory drugs, increase bleeding risk.^47,48 Aspirin and the nonsteroidals, in addition to having antiplatelet effects, also can cause gastric erosion.³⁷ In evaluating whether and when to restart anticoagulation, it is advisable to review the role that concomitant therapies may have had in the index bleeding event and to evaluate the risks and benefits of these other agents.

The factor that most consistently predicts major bleeding is a history of bleeding, particularly gastrointestinal bleeding

Additionally, warfarin has many interactions. Although the newer drugs are lauded for having fewer interactions, they are not completely free of them, and the potential for interactions must always be reviewed.⁴⁹ Further, unlike warfarin therapy, therapy with the newer agents is not routinely monitored with laboratory tests, so toxicity (or underdosing) may not be recognized until an adverse clinical event occurs. Ultimately, it may be safer to resume anticoagulation after a contributing drug can be safely discontinued.

Advanced age

The influence that the patient’s age should have on the decision to restart anticoagulation is unclear. Although the risk of intracranial hemorrhage increases with age, particularly after age 80, limited data exist in this population, particularly with regard to rebleeding. Further, age is a major risk factor for most thrombotic events, including venous thromboembolism and stroke from atrial fibrillation, so although the risks of anticoagulation may be higher, the benefits may also be higher than in younger patients.^37,46 We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage.

HOW LONG SHOULD WE WAIT TO RESTART ANTICOAGULATION?

We lack conclusive data on how long to wait to restart anticoagulation after an anticoagulation-associated hemorrhage.

The decision is complicated by evidence suggesting a rebound effect, with an increased risk of pulmonary embolism and atrial fibrillation-related stroke during the first 90 days of interruption of therapy with warfarin as well as with target-specific oral anticoagulants.^3–8 In anticoagulation-associated retroperitoneal bleeding, there is increased risk of deep vein thrombosis from compression, even if venous thromboembolism was not the initial indication for anticoagulation.³⁰

In patients with intracranial hemorrhage, evidence suggests that the intracranial hemorrhage itself increases the risk of arterial and venous thromboembolic events. Irrespective of whether a patient was previously on anticoagulation, the risk of arterial and venous thromboembolic events approaches 7% during the initial intracranial hemorrhage-related hospitalization and 9% during the first 90 days.^34,50,51

To date, the only information we have about when to resume anticoagulation comes from patients taking vitamin K antagonists.

Timing after gastrointestinal bleeding

Small case series suggest that in the first 2 months after warfarin-associated gastrointestinal bleeding, there is substantial risk of rebleeding when anticoagulation is resumed—and of thrombosis when it is not.^52,53 Two retrospective cohort studies may provide some guidance in this dilemma.^28,54

A workup for GI bleeding and gross hematuria uncovers previously undetected lesions in about one-third of cases involving warfarin

Witt et al²⁸ followed 442 patients who presented with gastrointestinal bleeding from any site during warfarin therapy for varied indications for up to 90 days after the index bleeding event. The risk of death was three times lower in patients who restarted warfarin than in those who did not, and their rate of thrombotic events was 10 times lower. The risk of recurrent gastrointestinal bleeding was statistically insignificant, and there were no fatal bleeding events. Anticoagulant therapy was generally resumed within 1 week of the bleeding event, at a median of 4 days.^28,55

Qureshi et al⁵⁴ performed a retrospective cohort study of 1,329 patients with  nonvalvular atrial fibrillation who had experienced a gastrointestinal hemorrhage while taking warfarin. They found that resuming warfarin after 7 days was not associated with a higher risk of recurrent gastrointestinal bleeding and that the rates of death and thromboembolism were lower than in patients who resumed warfarin after 30 days. On the other hand, the risk of recurrent gastrointestinal bleeding was significantly greater if therapy was resumed within the first week.

In view of these studies, we believe that most patients should resume anticoagulation after 4 to 7 days of interruption after gastrointestinal bleeding.⁵⁵

Timing after soft-tissue hemorrhage

The literature on resuming anticoagulation after soft-tissue hemorrhage is sparse. A retrospective study⁵² looked at this question in patients with spontaneous rectal sheath hematoma who had been receiving  antiplatelet drugs, intravenous heparin, vitamin K antagonists, or a combination of these, but not target-specific agents. More than half of the patients were on vitamin K antagonists at the time of hemorrhage. Analysis suggested that when benefits of resuming anticoagulation are believed to outweigh risks, it is reasonable to resume anticoagulation 4 days after the index event.⁵⁶

Timing after intracranial hemorrhage

Anticoagulation should not be considered within the first 24 hours after intracranial hemorrhage, as over 70% of patients develop some amount of hematoma expansion during this time.^34,57 The period thereafter poses a challenge, as the risk of hematoma expansion decreases while the risk of arterial and venous thromboembolism is ongoing and cumulative.⁵⁰

Perhaps surprisingly, national guidelines suggest starting prophylactic-dosed anticoagulation early in all intracranial hemorrhage patients, including those not previously on warfarin.^58,59 In a randomized trial, Boeer et al⁶⁰ concluded that starting low-dose subcutaneous heparin the day after an intracranial hemorrhage decreased the risk of thromboembolism without increasing the risk of rebleeding.⁶⁰ Dickmann et al⁶¹ similarly concluded that there was no increased risk of rebleeding with early prophylactic-dosed subcutaneous heparin.⁶¹ Optimal mechanical thromboprophylaxis, including graduated compression stockings and intermittent pneumatic compression stockings, is also encouraged.³⁴

We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage

Expert opinion remains divided on when and if anticoagulants should be resumed.^34,62 The American Heart Association suggests that in nonvalvular atrial fibrillation, long-term anticoagulation should be avoided after spontaneous lobar hemorrhage; antiplatelet agents can be considered instead.⁵⁸ In nonlobar hemorrhage, the American Heart Association suggests that anticoagulation be considered, depending on strength of indication, 7 to 10 days after the onset.⁵⁸ The European Stroke Initiative suggests patients with strong indications for anticoagulation be restarted on warfarin 10 to 14 days after the event, depending on the risk of thromboembolism and recurrent intracranial hemorrhage.⁵⁹ Others suggest delaying resumption to 10 to 30 weeks after an index intracranial hemorrhage.⁶³

Overall, in the immediate acute period of intracranial hemorrhage, most patients will likely benefit from acute reversal of anticoagulation, followed by institution of prophylactic-dose anticoagulation after the first 24 hours. Going forward, patients who remain at higher risk of a recurrence of anticoagulant-related intracranial hemorrhage (such as those with lobar hemorrhage, suspected cerebral amyloid angiopathy, and other high-risk factors) than of thromboembolic events may be best managed without anticoagulants. Alternatively, patients with deep hemispheric intracranial hemorrhage, hypertension that can be well controlled, and a high risk of serious thromboembolism may experience net benefit from restarting anticoagulation.³⁴

We recommend considering restarting anticoagulation 7 days after the onset of intracranial hemorrhage in patients at high risk of thromboembolism and after at least 14 days for patients at lower risk (Table 2). Discussions with neurologic and neurosurgical consultants should also inform this timing decision.

WOULD A NEWER DRUG BE A BETTER CHOICE?

The emergence of target-specific oral anticoagulants, including factor Xa inhibitors such as rivaroxaban, apixaban, and edoxaban and the direct thrombin inhibitor dabigatran etexilate, presents further challenges in managing anticoagulation after hemorrhage. Table 4 summarizes the current FDA-approved indications.^64–67

These newer agents are attractive because, compared with warfarin, they have wider therapeutic windows, faster onset and offset of action, and fewer drug and food interactions.⁶⁸ A meta-analysis of data available to date suggests that the new drugs, compared with warfarin, show a favorable risk-benefit profile with reductions in stroke, intracranial hemorrhage, and mortality with similar overall major bleeding rates, except for a possible increase in gastrointestinal bleeding.⁶⁸

However, when managing anticoagulation after a bleeding event, the newer agents are challenging for two reasons: they may be associated with a higher incidence of gastrointestinal bleeding than warfarin, and they lack the typical reversal agents that can be used to manage an acute bleeding event.^68,69

In individual studies comparing warfarin with dabigatran,⁷⁰ rivaroxaban,⁷¹ apixaban,⁷² or edoxaban⁷³ for stroke prevention in patients with atrial fibrillation, there was no significant difference in the rate of major bleeding between dabigatran in its higher dose (150 mg twice a day) or rivaroxaban compared with warfarin.^70,71 The risk of major bleeding was actually lower with apixaban⁷² and edoxaban.⁷³

In regard to specific types of major bleeding, the rate of intracranial hemorrhage was significantly lower with dabigatran, rivaroxaban, apixaban, and edoxaban than with warfarin.^35,68–73 Some have proposed that since the brain is high in tissue factor, inhibition of tissue factor-factor VIIa complexes by vitamin K antagonists leaves the brain vulnerable to hemorrhage. Others suggest that the targeted mechanism of target-specific agents, as opposed to the multiple pathways in both the intrinsic and extrinsic coagulation cascade that vitamin K antagonists affect, may explain this difference.^35,74,75

However, some studies suggest that rivaroxaban and the higher doses of dabigatran and edoxaban are associated with higher rates of major gastrointestinal bleeding compared with warfarin.^69–71,76 But apixaban demonstrated no significant difference in gastrointestinal bleeding, and instead demonstrated rates of gastrointestinal bleeding comparable to that with aspirin for stroke prevention in atrial fibrillation.⁷²

The new oral anticoagulants lack antidotes or reversal agents such as phytonadione and fresh-frozen plasma that are available to manage warfarin-associated bleeding events. Other proposed reversal options for the new agents include activated charcoal (if the drugs were taken recently enough to remain in the gastrointestinal tract) and concentrated clotting factor product, though research is ongoing in regards to the most appropriate use in clinical practice.^37,69 Unlike rivaroxaban and apixaban, dabigatran has low plasma protein binding and is dialyzable, which provides another strategy in managing dabigatran-related bleeding.⁶⁹

We believe most patients should resume anticoagulation after 4 to 7 days of interruption after GI bleeding

Of note, the above bleeding risk calculations relate to the first anticoagulant-related bleeding event, though presumably the same risk comparison across agents may be applicable to rebleeding events. Given the data above, when anticoagulation is to be resumed after an intracranial hemorrhage, the risk of rebleeding, particularly in the form of recurrent intracranial hemorrhage, may be lower if a target-specific oral anticoagulant is used.⁷⁵ Similarly, when anticoagulation is to be resumed after a gastrointestinal bleeding event, reinitiation with warfarin or apixaban therapy may present the lowest risk of recurrent gastrointestinal rebleeding. In other sources of bleeding, such as retroperitoneal bleeding, we suggest consideration of transitioning to warfarin, given the availability of reversal agents in the event of recurrent bleeding.

Other important drug-specific factors that must be noted when selecting an agent with which to resume anticoagulation after a hemorrhage include the following:

• In patients with significant renal impairment, the choice of agent will be limited to a vitamin K antagonist.⁷⁷
• A meta-analysis of randomized clinical trials suggests that in the elderly (age 75 and older) target-specific oral anticoagulants did not cause excess bleeding and were associated with at least equal efficacy compared with vitamin K antagonists.⁷⁸
• Target-specific oral anticoagulants may be beneficial in patients who have challenges in achieving INR targets, as evidence suggests that switching to them is associated with a reduction in bleeding for patients who struggle to maintain an appropriately therapeutic INR.⁶⁸ On the other hand, if there is concern that a patient may occasionally miss doses of an anticoagulant, given the rapid onset and offset of action of target-specific agents compared with warfarin, a missed dose of a target-specific agent may result in faster dissolution of anticoagulant effect and increased risk of thrombotic events, and lapses in anticoagulation will not be identified by routine drug monitoring.^6–8,75 As such, it is vital to have a frank discussion with any patient who has difficulty maintaining therapeutic INRs on warfarin treatment to make sure that he or she is not missing doses.
• If there is no clear and compelling reason to select a particular agent, cost considerations should be taken into account. We have included estimated 30-day pricing for the various agents in Table 4. 

If a patient receiving anticoagulant therapy suffers a bleeding event, the patient and physician must decide whether and how soon to restart the therapy, and with what agent.

Foremost on our minds tends to be the risk of another hemorrhage. Subtler to appreciate immediately after an event is the continued risk of thrombosis, often from the same medical condition that prompted anticoagulation therapy in the first place (Table 1).

Complicating the decision, there may be a rebound effect: some thrombotic events such as pulmonary embolism and atrial fibrillation-related stroke may be more likely to occur in the first weeks after stopping warfarin than during similar intervals in patients who have not been taking it.^1–3 The same thing may happen with the newer, target-specific oral anticoagulants.^4–6

Although we have evidence-based guidelines for initiating and managing anticoagulant therapy, ample data on adverse events, and protocols for reversing anticoagulation if bleeding occurs, we do not have clear guidelines on restarting anticoagulation after a hemorrhagic event.

In this article, we outline a practical framework for approaching this clinical dilemma. Used in conjunction with consideration of a patient’s values and preferences as well as input from experts, this framework can help clinicians guide their patients through this challenging clinical decision. It consists of five questions:

• Why is the patient on anticoagulation, and what is the risk of thromboembolism without it?
• What was the clinical impact of the hemorrhage, and what is the risk of rebleeding if anticoagulation is resumed?
• What additional patient factors should be taken into consideration?
• How long should we wait before restarting anticoagulation?
• Would a newer drug be a better choice?

BLEEDING OCCURS IN 2% TO 3% OF PATIENTS PER YEAR

Most of our information on anticoagulation is about vitamin K antagonists—principally warfarin, in use since the 1950s. Among patients taking warfarin outside of clinical trials, the risk of major bleeding is estimated at 2% to 3% per year.⁷

However, the target-specific oral anticoagulants rivaroxaban (Xarelto), apixaban (Eliquis),  dabigatran (Pradaxa) and edoxaban (Savaysa) are being used more and more, and we include them in our discussion insofar as we have information on them. The rates of bleeding with these new drugs in clinical trials have been comparable to or lower than those with warfarin.⁸ Postmarketing surveillance is under way.

WHY IS THE PATIENT ON ANTICOAGULATION? WHAT IS THE RISK WITHOUT IT?

Common, evidence-based indications for anticoagulation are to prevent complications in patients with venous thromboembolism and to prevent stroke in patients with atrial fibrillation or a mechanical heart valve. Other uses, such as in heart failure and its sequelae, pulmonary hypertension, and splanchnic or hepatic vein thrombosis, have less robust evidence to support them.

When anticoagulation-related bleeding occurs, it is essential to review why the patient is taking the drug and the risk of thromboembolism without it. Some indications pose a higher risk of thromboembolism than others and so argue more strongly for continuing the treatment.

Douketis et al⁹ developed a risk-stratification scheme for perioperative thromboembolism. We have modified it by adding the CHA₂DS₂-VASc score (Table 2),^9–11 and believe it can be used more widely.

High-risk indications

Conditions that pose a high risk of thrombosis almost always require restarting anticoagulation. Here, the most appropriate question nearly always is not if anticoagulation should be restarted, but when. Examples:

• A mechanical mitral valve
• Antiphospholipid antibody syndrome with recurrent thromboembolic events.

Lower-risk indications

Lower-risk indications allow more leeway in determining if anticoagulation should be resumed. The most straightforward cases fall well within established guidelines. Examples:

• Atrial fibrillation and a CHA₂DS₂-VASc score of 1. The 2014 guidelines from the American College of Cardiology, American Heart Association, and Heart Rhythm Society¹⁰ suggest that patients with nonvalvular atrial fibrillation and a CHA₂DS₂-VASc score of 1 have three options: an oral anticoagulant, aspirin, and no antithrombotic therapy. If such a patient on anticoagulant therapy subsequently experiences a major gastrointestinal hemorrhage requiring transfusion and intensive care and no definitively treatable source of bleeding is found on endoscopy, one can argue that the risks of continued anticoagulation (recurrent bleeding) now exceed the benefits and that the patient would be better served by aspirin or even no antithrombotic therapy.

• After 6 months of anticoagulation for unprovoked deep vein thrombosis. Several studies showed that aspirin reduced the risk of recurrent venous thromboembolism in patients who completed an initial 6-month course of anticoagulation.^12–15 Though these studies did not specifically compare aspirin with warfarin or target-specific oral anticoagulants in preventing recurrent venous thromboembolism after a hemorrhage, it is reasonable to extrapolate their results to this situation.

If the risk of recurrent hemorrhage on anticoagulation is considered to be too great, then aspirin is an alternative to no anticoagulation, as it reduces the risk of recurrent venous thromboembolism.¹⁶ However, we advise caution if the bleeding lesion may be specifically exacerbated by aspirin, particularly upper gastrointestinal ulcers.

Moderate-risk indications

• After a partial course of anticoagulation for provoked venous thromboembolism. Suppose a patient in the 10th week of a planned 12-week course of anticoagulation for a surgically provoked, first deep vein thrombosis presents with abdominal pain and is found to have a retroperitoneal hematoma. In light of the risk of recurrent bleeding vs the benefit of resuming anticoagulation for the limited remaining period, her 12-week treatment course can reasonably be shortened to 10 weeks.

The risk of recurrent venous thromboembolism when a patient is off anticoagulation decreases with time from the initial event. The highest risk, estimated at 0.3% to 1.3% per day, is in the first 4 weeks, falling to 0.03% to 0.2% per day in weeks 5 through 12, and 0.05% per day thereafter.^17–20

The risk of recurrent venous thromboembolism is greatest immediately after the event and decreases over time

Additionally, a pooled analysis of seven randomized trials suggests that patients with isolated, distal deep vein thrombosis provoked by a temporary risk factor did not have a high risk of recurrence after being treated for 4 to 6 weeks.²¹ These analyses are based on vitamin K antagonists, though it seems reasonable to extrapolate this information to the target-specific oral anticoagulants.

More challenging are situations in which the evidence supporting the initial or continued need for anticoagulation is less robust, such as in heart failure, pulmonary hypertension, or splanchnic and hepatic vein thrombosis. In these cases, the lack of strong evidence supporting the use of anticoagulation should make us hesitate to resume it after bleeding.

WHAT WAS THE CLINICAL IMPACT? WHAT IS THE RISK OF REBLEEDING?

Different groups have defined major and minor bleeding in different ways.^22,23 Several have proposed criteria to standardize how bleeding events (on warfarin and otherwise) are classified,^23–25 but the definitions differ.

Specifically, all agree that a “major” bleeding event is one that is fatal, involves bleeding into a major organ, or leads to a substantial decline in hemoglobin level. However, the Thrombolysis in Myocardial Infarction trials use a decline of more than 5 g/dL in their definition,^23,25 while the International Society on Thrombosis and Haemostasis uses 2 g/dL.²⁴

Here, we review the clinical impact of the most common sources of anticoagulation-related hemorrhage—gastrointestinal, soft tissue, and urinary tract²⁶—as well as intracerebral hemorrhage, a less common but more uniformly devastating event.²⁷

Clinical impact of gastrointestinal hemorrhage

Each year, about 4.5% of patients taking warfarin have a gastrointestinal hemorrhage, though not all of these events are major.²⁸ Evolving data suggest that the newer agents (particularly dabigatran, rivaroxaban, and edoxaban) pose a higher risk of gastrointestinal bleeding than warfarin.²⁹ Patients may need plasma and blood transfusions and intravenous phytonadione, all of which carry risks, albeit small.

Frequently, endoscopy is needed to find the source of bleeding and to control it. If this does not work, angiographic intervention to infuse vasoconstrictors or embolic coils into the culprit artery may be required, and some patients need surgery. Each intervention carries its own risk.

Clinical impact of soft-tissue hemorrhage

Soft-tissue hemorrhage accounts for more than 20% of warfarin-related bleeding events²⁶; as yet, we know of no data on the rate with the new drugs. Soft-tissue hemorrhage is often localized to the large muscles of the retroperitoneum and legs. Though retroperitoneal hemorrhage accounts for a relatively small portion of soft-tissue hemorrhages, it is associated with high rates of morbidity and death and will therefore be our focus.²⁶

Some indications for anticoagulation pose a higher risk of thromboembolism than others

Much of the clinical impact of retroperitoneal hemorrhage is from a mass effect that causes abdominal compartment syndrome, hydroureter, ileus, abscess formation, and acute and chronic pain. At least 20% of cases are associated with femoral neuropathy. It can also lead to deep vein thrombosis from venous compression, coupled with hypercoagulability in response to bleeding. Brisk bleeding can lead to shock and death, and the mortality rate in retroperitoneal hemorrhage is estimated at 20% or higher.³⁰

In many cases, the retroperitoneal hemorrhage will self-tamponade and the blood will be reabsorbed once the bleeding has stopped, but uncontrolled bleeding may require surgical or angiographic intervention.³⁰

Clinical impact of urinary tract hemorrhage

Gross or microscopic hematuria can be found in an estimated 2% to 24% of patients taking warfarin^31–33; data are lacking for the target-specific oral anticoagulants. Interventions required to manage urinary tract bleeding include bladder irrigation and, less often, transfusion.³¹ Since a significant number of cases of hematuria are due to neoplastic disease,³² a diagnostic workup with radiographic imaging of the upper tract and cystoscopy of the lower tract is usually required.³¹ While life-threatening hemorrhage is uncommon, complications such as transient urinary obstruction from clots may occur.

Clinical impact of intracranial hemorrhage

Intracranial hemorrhage is the most feared and deadly of the bleeding complications of anticoagulation. The incidence in patients on warfarin is estimated at 2% to 3% per year, which is markedly higher than the estimated incidence of 25 per 100,000 person-years in the general population.³⁴ Emerging data indicate that the newer drugs are also associated with a risk of intracranial hemorrhage, though the risk is about half that with vitamin K antagonists.³⁵ Intracranial hemorrhage leads to death or disability in 76% of cases, compared with 3% of cases of bleeding from the gastrointestinal or urinary tract.²⁷

Regardless of the source of bleeding, hospitalization is likely to be required and may be  prolonged, with attendant risks of nosocomial harms such as infection.

Risk of rebleeding

Given the scope and severity of anticoagulation-related bleeding, there is strong interest in predicting and preventing it. By some estimates, the incidence of recurrent bleeding after resuming vitamin K antagonists is 8% to 13%.²² Although there are several indices for predicting the risk of major bleeding when starting anticoagulation, there are currently no validated tools to estimate a patient’s risk of rebleeding.³⁶

The patient factor that most consistently predicts major bleeding is a history of bleeding, particularly from the gastrointestinal tract. Finding and controlling the source of bleeding is important.^26,37 For example, a patient with gross hematuria who is found on cystoscopy to have a urothelial papilloma is unlikely to have rebleeding if the tumor is successfully resected and serial follow-up shows no regrowth. In contrast, consider a patient with a major gastrointestinal hemorrhage, the source of which remains elusive after upper, lower, and capsule endoscopy or, alternatively, is suspected to be from one of multiple angiodysplastic lesions. Without definitive source management, this patient faces a high risk of rebleeding.

With or without anticoagulation, after a first intracranial hemorrhage the risk of another one is estimated at 2% to 4% per year.³⁴ An observational study found a recurrence rate of 7.5% when vitamin K antagonist therapy was started after an intracranial hemorrhage (though not all patients were on a vitamin K antagonist at the time of the first hemorrhage).³⁸

Evolving data suggest the newer oral agents pose a higher risk of GI bleeding

Patients with lobar hemorrhage and those with suspected cerebral amyloid angiopathy may be at particularly high risk if anticoagulation is resumed. Conversely, initial events attributed to uncontrolled hypertension that subsequently can be well controlled may portend a lower risk of rebleeding.³⁴ For other types of intracranial hemorrhage, recurrence rates can be even higher. Irrespective of anticoagulation, one prospective study estimated the crude annual rebleeding rate with untreated arteriovenous malformations to be 7%.³⁹ In chronic subdural hematoma, the recurrence rate after initial drainage has been estimated at 9.2% to 26.5%, with use of anticoagulants (in this case, vitamin K antagonists) being an independent predictor of recurrence.⁴⁰

WHAT OTHER PATIENT FACTORS NEED CONSIDERATION?

Target INR on warfarin

An important factor influencing the risk of bleeding with warfarin is the intensity of this therapy.³⁷ A meta-analysis⁴¹ found that the risks of major hemorrhage and thromboembolism are minimized if the goal international normalized ratio (INR) is 2.0 to 3.0. When considering resuming anticoagulation after bleeding, make sure the therapeutic target is appropriate.³⁷

Table 3 summarizes recommended therapeutic ranges for frequently encountered indications for warfarin.^36,42,43

INR at time of the event and challenges in controlling it

The decision to resume anticoagulation in patients who bled while using warfarin must take into account the actual INR at the time of the event.

For example, consider a patient whose INR values are consistently in the therapeutic range.  While on vacation, he receives ciprofloxacin for acute prostatitis from an urgent care team, and no adjustment to INR monitoring or warfarin dose is made. Several days later, he presents with lower gastrointestinal bleeding. His INR is 8, and colonoscopy reveals diverticulosis with a bleeding vessel, responsive to endoscopic therapy. After controlling the source of bleeding and reinforcing the need to always review new medications for potential interactions with anticoagulation, it is reasonable to expect that he once again will be able to keep his INR in the therapeutic range.

A patient on anticoagulation for the same indication but who has a history of repeated supratherapeutic levels, poor adherence, or poor access to INR monitoring poses very different concerns about resuming anticoagulation (as well as which agent to use, as we discuss below).

Of note, a high INR alone does not explain bleeding. It is estimated that a workup for gastrointestinal bleeding and gross hematuria uncovers previously undetected lesions in approximately one-third of cases involving warfarin.²⁶ A similar malignancy-unmasking effect is now recognized in patients using the target-specific oral agents who experience gastrointestinal bleeding.⁴⁴ Accordingly, we recommend a comprehensive source evaluation for any anticoagulation-related hemorrhage.

Comorbid conditions

Comorbid conditions associated with bleeding include cancer, end-stage renal disease, liver disease, arterial hypertension, prior stroke, and alcohol abuse.^37,45 Gait instability, regardless of cause, may also increase the risk of trauma-related hemorrhage, but some have estimated that a patient would need to fall multiple times per week to contraindicate anticoagulation on the basis of falls alone.⁴⁶

Concurrent medications

Concomitant therapies, including antiplatelet drugs and nonsteroidal anti-inflammatory drugs, increase bleeding risk.^47,48 Aspirin and the nonsteroidals, in addition to having antiplatelet effects, also can cause gastric erosion.³⁷ In evaluating whether and when to restart anticoagulation, it is advisable to review the role that concomitant therapies may have had in the index bleeding event and to evaluate the risks and benefits of these other agents.

The factor that most consistently predicts major bleeding is a history of bleeding, particularly gastrointestinal bleeding

Additionally, warfarin has many interactions. Although the newer drugs are lauded for having fewer interactions, they are not completely free of them, and the potential for interactions must always be reviewed.⁴⁹ Further, unlike warfarin therapy, therapy with the newer agents is not routinely monitored with laboratory tests, so toxicity (or underdosing) may not be recognized until an adverse clinical event occurs. Ultimately, it may be safer to resume anticoagulation after a contributing drug can be safely discontinued.

Advanced age

The influence that the patient’s age should have on the decision to restart anticoagulation is unclear. Although the risk of intracranial hemorrhage increases with age, particularly after age 80, limited data exist in this population, particularly with regard to rebleeding. Further, age is a major risk factor for most thrombotic events, including venous thromboembolism and stroke from atrial fibrillation, so although the risks of anticoagulation may be higher, the benefits may also be higher than in younger patients.^37,46 We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage.

HOW LONG SHOULD WE WAIT TO RESTART ANTICOAGULATION?

We lack conclusive data on how long to wait to restart anticoagulation after an anticoagulation-associated hemorrhage.

The decision is complicated by evidence suggesting a rebound effect, with an increased risk of pulmonary embolism and atrial fibrillation-related stroke during the first 90 days of interruption of therapy with warfarin as well as with target-specific oral anticoagulants.^3–8 In anticoagulation-associated retroperitoneal bleeding, there is increased risk of deep vein thrombosis from compression, even if venous thromboembolism was not the initial indication for anticoagulation.³⁰

In patients with intracranial hemorrhage, evidence suggests that the intracranial hemorrhage itself increases the risk of arterial and venous thromboembolic events. Irrespective of whether a patient was previously on anticoagulation, the risk of arterial and venous thromboembolic events approaches 7% during the initial intracranial hemorrhage-related hospitalization and 9% during the first 90 days.^34,50,51

To date, the only information we have about when to resume anticoagulation comes from patients taking vitamin K antagonists.

Timing after gastrointestinal bleeding

Small case series suggest that in the first 2 months after warfarin-associated gastrointestinal bleeding, there is substantial risk of rebleeding when anticoagulation is resumed—and of thrombosis when it is not.^52,53 Two retrospective cohort studies may provide some guidance in this dilemma.^28,54

A workup for GI bleeding and gross hematuria uncovers previously undetected lesions in about one-third of cases involving warfarin

Witt et al²⁸ followed 442 patients who presented with gastrointestinal bleeding from any site during warfarin therapy for varied indications for up to 90 days after the index bleeding event. The risk of death was three times lower in patients who restarted warfarin than in those who did not, and their rate of thrombotic events was 10 times lower. The risk of recurrent gastrointestinal bleeding was statistically insignificant, and there were no fatal bleeding events. Anticoagulant therapy was generally resumed within 1 week of the bleeding event, at a median of 4 days.^28,55

Qureshi et al⁵⁴ performed a retrospective cohort study of 1,329 patients with  nonvalvular atrial fibrillation who had experienced a gastrointestinal hemorrhage while taking warfarin. They found that resuming warfarin after 7 days was not associated with a higher risk of recurrent gastrointestinal bleeding and that the rates of death and thromboembolism were lower than in patients who resumed warfarin after 30 days. On the other hand, the risk of recurrent gastrointestinal bleeding was significantly greater if therapy was resumed within the first week.

In view of these studies, we believe that most patients should resume anticoagulation after 4 to 7 days of interruption after gastrointestinal bleeding.⁵⁵

Timing after soft-tissue hemorrhage

The literature on resuming anticoagulation after soft-tissue hemorrhage is sparse. A retrospective study⁵² looked at this question in patients with spontaneous rectal sheath hematoma who had been receiving  antiplatelet drugs, intravenous heparin, vitamin K antagonists, or a combination of these, but not target-specific agents. More than half of the patients were on vitamin K antagonists at the time of hemorrhage. Analysis suggested that when benefits of resuming anticoagulation are believed to outweigh risks, it is reasonable to resume anticoagulation 4 days after the index event.⁵⁶

Timing after intracranial hemorrhage

Anticoagulation should not be considered within the first 24 hours after intracranial hemorrhage, as over 70% of patients develop some amount of hematoma expansion during this time.^34,57 The period thereafter poses a challenge, as the risk of hematoma expansion decreases while the risk of arterial and venous thromboembolism is ongoing and cumulative.⁵⁰

Perhaps surprisingly, national guidelines suggest starting prophylactic-dosed anticoagulation early in all intracranial hemorrhage patients, including those not previously on warfarin.^58,59 In a randomized trial, Boeer et al⁶⁰ concluded that starting low-dose subcutaneous heparin the day after an intracranial hemorrhage decreased the risk of thromboembolism without increasing the risk of rebleeding.⁶⁰ Dickmann et al⁶¹ similarly concluded that there was no increased risk of rebleeding with early prophylactic-dosed subcutaneous heparin.⁶¹ Optimal mechanical thromboprophylaxis, including graduated compression stockings and intermittent pneumatic compression stockings, is also encouraged.³⁴

We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage

Expert opinion remains divided on when and if anticoagulants should be resumed.^34,62 The American Heart Association suggests that in nonvalvular atrial fibrillation, long-term anticoagulation should be avoided after spontaneous lobar hemorrhage; antiplatelet agents can be considered instead.⁵⁸ In nonlobar hemorrhage, the American Heart Association suggests that anticoagulation be considered, depending on strength of indication, 7 to 10 days after the onset.⁵⁸ The European Stroke Initiative suggests patients with strong indications for anticoagulation be restarted on warfarin 10 to 14 days after the event, depending on the risk of thromboembolism and recurrent intracranial hemorrhage.⁵⁹ Others suggest delaying resumption to 10 to 30 weeks after an index intracranial hemorrhage.⁶³

Overall, in the immediate acute period of intracranial hemorrhage, most patients will likely benefit from acute reversal of anticoagulation, followed by institution of prophylactic-dose anticoagulation after the first 24 hours. Going forward, patients who remain at higher risk of a recurrence of anticoagulant-related intracranial hemorrhage (such as those with lobar hemorrhage, suspected cerebral amyloid angiopathy, and other high-risk factors) than of thromboembolic events may be best managed without anticoagulants. Alternatively, patients with deep hemispheric intracranial hemorrhage, hypertension that can be well controlled, and a high risk of serious thromboembolism may experience net benefit from restarting anticoagulation.³⁴

We recommend considering restarting anticoagulation 7 days after the onset of intracranial hemorrhage in patients at high risk of thromboembolism and after at least 14 days for patients at lower risk (Table 2). Discussions with neurologic and neurosurgical consultants should also inform this timing decision.

WOULD A NEWER DRUG BE A BETTER CHOICE?

The emergence of target-specific oral anticoagulants, including factor Xa inhibitors such as rivaroxaban, apixaban, and edoxaban and the direct thrombin inhibitor dabigatran etexilate, presents further challenges in managing anticoagulation after hemorrhage. Table 4 summarizes the current FDA-approved indications.^64–67

These newer agents are attractive because, compared with warfarin, they have wider therapeutic windows, faster onset and offset of action, and fewer drug and food interactions.⁶⁸ A meta-analysis of data available to date suggests that the new drugs, compared with warfarin, show a favorable risk-benefit profile with reductions in stroke, intracranial hemorrhage, and mortality with similar overall major bleeding rates, except for a possible increase in gastrointestinal bleeding.⁶⁸

However, when managing anticoagulation after a bleeding event, the newer agents are challenging for two reasons: they may be associated with a higher incidence of gastrointestinal bleeding than warfarin, and they lack the typical reversal agents that can be used to manage an acute bleeding event.^68,69

In individual studies comparing warfarin with dabigatran,⁷⁰ rivaroxaban,⁷¹ apixaban,⁷² or edoxaban⁷³ for stroke prevention in patients with atrial fibrillation, there was no significant difference in the rate of major bleeding between dabigatran in its higher dose (150 mg twice a day) or rivaroxaban compared with warfarin.^70,71 The risk of major bleeding was actually lower with apixaban⁷² and edoxaban.⁷³

In regard to specific types of major bleeding, the rate of intracranial hemorrhage was significantly lower with dabigatran, rivaroxaban, apixaban, and edoxaban than with warfarin.^35,68–73 Some have proposed that since the brain is high in tissue factor, inhibition of tissue factor-factor VIIa complexes by vitamin K antagonists leaves the brain vulnerable to hemorrhage. Others suggest that the targeted mechanism of target-specific agents, as opposed to the multiple pathways in both the intrinsic and extrinsic coagulation cascade that vitamin K antagonists affect, may explain this difference.^35,74,75

However, some studies suggest that rivaroxaban and the higher doses of dabigatran and edoxaban are associated with higher rates of major gastrointestinal bleeding compared with warfarin.^69–71,76 But apixaban demonstrated no significant difference in gastrointestinal bleeding, and instead demonstrated rates of gastrointestinal bleeding comparable to that with aspirin for stroke prevention in atrial fibrillation.⁷²

The new oral anticoagulants lack antidotes or reversal agents such as phytonadione and fresh-frozen plasma that are available to manage warfarin-associated bleeding events. Other proposed reversal options for the new agents include activated charcoal (if the drugs were taken recently enough to remain in the gastrointestinal tract) and concentrated clotting factor product, though research is ongoing in regards to the most appropriate use in clinical practice.^37,69 Unlike rivaroxaban and apixaban, dabigatran has low plasma protein binding and is dialyzable, which provides another strategy in managing dabigatran-related bleeding.⁶⁹

We believe most patients should resume anticoagulation after 4 to 7 days of interruption after GI bleeding

Of note, the above bleeding risk calculations relate to the first anticoagulant-related bleeding event, though presumably the same risk comparison across agents may be applicable to rebleeding events. Given the data above, when anticoagulation is to be resumed after an intracranial hemorrhage, the risk of rebleeding, particularly in the form of recurrent intracranial hemorrhage, may be lower if a target-specific oral anticoagulant is used.⁷⁵ Similarly, when anticoagulation is to be resumed after a gastrointestinal bleeding event, reinitiation with warfarin or apixaban therapy may present the lowest risk of recurrent gastrointestinal rebleeding. In other sources of bleeding, such as retroperitoneal bleeding, we suggest consideration of transitioning to warfarin, given the availability of reversal agents in the event of recurrent bleeding.

Other important drug-specific factors that must be noted when selecting an agent with which to resume anticoagulation after a hemorrhage include the following:

• In patients with significant renal impairment, the choice of agent will be limited to a vitamin K antagonist.⁷⁷
• A meta-analysis of randomized clinical trials suggests that in the elderly (age 75 and older) target-specific oral anticoagulants did not cause excess bleeding and were associated with at least equal efficacy compared with vitamin K antagonists.⁷⁸
• Target-specific oral anticoagulants may be beneficial in patients who have challenges in achieving INR targets, as evidence suggests that switching to them is associated with a reduction in bleeding for patients who struggle to maintain an appropriately therapeutic INR.⁶⁸ On the other hand, if there is concern that a patient may occasionally miss doses of an anticoagulant, given the rapid onset and offset of action of target-specific agents compared with warfarin, a missed dose of a target-specific agent may result in faster dissolution of anticoagulant effect and increased risk of thrombotic events, and lapses in anticoagulation will not be identified by routine drug monitoring.^6–8,75 As such, it is vital to have a frank discussion with any patient who has difficulty maintaining therapeutic INRs on warfarin treatment to make sure that he or she is not missing doses.
• If there is no clear and compelling reason to select a particular agent, cost considerations should be taken into account. We have included estimated 30-day pricing for the various agents in Table 4. 

If a patient receiving anticoagulant therapy suffers a bleeding event, the patient and physician must decide whether and how soon to restart the therapy, and with what agent.

Foremost on our minds tends to be the risk of another hemorrhage. Subtler to appreciate immediately after an event is the continued risk of thrombosis, often from the same medical condition that prompted anticoagulation therapy in the first place (Table 1).

Complicating the decision, there may be a rebound effect: some thrombotic events such as pulmonary embolism and atrial fibrillation-related stroke may be more likely to occur in the first weeks after stopping warfarin than during similar intervals in patients who have not been taking it.^1–3 The same thing may happen with the newer, target-specific oral anticoagulants.^4–6

Although we have evidence-based guidelines for initiating and managing anticoagulant therapy, ample data on adverse events, and protocols for reversing anticoagulation if bleeding occurs, we do not have clear guidelines on restarting anticoagulation after a hemorrhagic event.

In this article, we outline a practical framework for approaching this clinical dilemma. Used in conjunction with consideration of a patient’s values and preferences as well as input from experts, this framework can help clinicians guide their patients through this challenging clinical decision. It consists of five questions:

• Why is the patient on anticoagulation, and what is the risk of thromboembolism without it?
• What was the clinical impact of the hemorrhage, and what is the risk of rebleeding if anticoagulation is resumed?
• What additional patient factors should be taken into consideration?
• How long should we wait before restarting anticoagulation?
• Would a newer drug be a better choice?

BLEEDING OCCURS IN 2% TO 3% OF PATIENTS PER YEAR

Most of our information on anticoagulation is about vitamin K antagonists—principally warfarin, in use since the 1950s. Among patients taking warfarin outside of clinical trials, the risk of major bleeding is estimated at 2% to 3% per year.⁷

However, the target-specific oral anticoagulants rivaroxaban (Xarelto), apixaban (Eliquis),  dabigatran (Pradaxa) and edoxaban (Savaysa) are being used more and more, and we include them in our discussion insofar as we have information on them. The rates of bleeding with these new drugs in clinical trials have been comparable to or lower than those with warfarin.⁸ Postmarketing surveillance is under way.

WHY IS THE PATIENT ON ANTICOAGULATION? WHAT IS THE RISK WITHOUT IT?

Common, evidence-based indications for anticoagulation are to prevent complications in patients with venous thromboembolism and to prevent stroke in patients with atrial fibrillation or a mechanical heart valve. Other uses, such as in heart failure and its sequelae, pulmonary hypertension, and splanchnic or hepatic vein thrombosis, have less robust evidence to support them.

When anticoagulation-related bleeding occurs, it is essential to review why the patient is taking the drug and the risk of thromboembolism without it. Some indications pose a higher risk of thromboembolism than others and so argue more strongly for continuing the treatment.

Douketis et al⁹ developed a risk-stratification scheme for perioperative thromboembolism. We have modified it by adding the CHA₂DS₂-VASc score (Table 2),^9–11 and believe it can be used more widely.

High-risk indications

Conditions that pose a high risk of thrombosis almost always require restarting anticoagulation. Here, the most appropriate question nearly always is not if anticoagulation should be restarted, but when. Examples:

• A mechanical mitral valve
• Antiphospholipid antibody syndrome with recurrent thromboembolic events.

Lower-risk indications

Lower-risk indications allow more leeway in determining if anticoagulation should be resumed. The most straightforward cases fall well within established guidelines. Examples:

• Atrial fibrillation and a CHA₂DS₂-VASc score of 1. The 2014 guidelines from the American College of Cardiology, American Heart Association, and Heart Rhythm Society¹⁰ suggest that patients with nonvalvular atrial fibrillation and a CHA₂DS₂-VASc score of 1 have three options: an oral anticoagulant, aspirin, and no antithrombotic therapy. If such a patient on anticoagulant therapy subsequently experiences a major gastrointestinal hemorrhage requiring transfusion and intensive care and no definitively treatable source of bleeding is found on endoscopy, one can argue that the risks of continued anticoagulation (recurrent bleeding) now exceed the benefits and that the patient would be better served by aspirin or even no antithrombotic therapy.

• After 6 months of anticoagulation for unprovoked deep vein thrombosis. Several studies showed that aspirin reduced the risk of recurrent venous thromboembolism in patients who completed an initial 6-month course of anticoagulation.^12–15 Though these studies did not specifically compare aspirin with warfarin or target-specific oral anticoagulants in preventing recurrent venous thromboembolism after a hemorrhage, it is reasonable to extrapolate their results to this situation.

If the risk of recurrent hemorrhage on anticoagulation is considered to be too great, then aspirin is an alternative to no anticoagulation, as it reduces the risk of recurrent venous thromboembolism.¹⁶ However, we advise caution if the bleeding lesion may be specifically exacerbated by aspirin, particularly upper gastrointestinal ulcers.

Moderate-risk indications

• After a partial course of anticoagulation for provoked venous thromboembolism. Suppose a patient in the 10th week of a planned 12-week course of anticoagulation for a surgically provoked, first deep vein thrombosis presents with abdominal pain and is found to have a retroperitoneal hematoma. In light of the risk of recurrent bleeding vs the benefit of resuming anticoagulation for the limited remaining period, her 12-week treatment course can reasonably be shortened to 10 weeks.

The risk of recurrent venous thromboembolism when a patient is off anticoagulation decreases with time from the initial event. The highest risk, estimated at 0.3% to 1.3% per day, is in the first 4 weeks, falling to 0.03% to 0.2% per day in weeks 5 through 12, and 0.05% per day thereafter.^17–20

The risk of recurrent venous thromboembolism is greatest immediately after the event and decreases over time

Additionally, a pooled analysis of seven randomized trials suggests that patients with isolated, distal deep vein thrombosis provoked by a temporary risk factor did not have a high risk of recurrence after being treated for 4 to 6 weeks.²¹ These analyses are based on vitamin K antagonists, though it seems reasonable to extrapolate this information to the target-specific oral anticoagulants.

More challenging are situations in which the evidence supporting the initial or continued need for anticoagulation is less robust, such as in heart failure, pulmonary hypertension, or splanchnic and hepatic vein thrombosis. In these cases, the lack of strong evidence supporting the use of anticoagulation should make us hesitate to resume it after bleeding.

WHAT WAS THE CLINICAL IMPACT? WHAT IS THE RISK OF REBLEEDING?

Different groups have defined major and minor bleeding in different ways.^22,23 Several have proposed criteria to standardize how bleeding events (on warfarin and otherwise) are classified,^23–25 but the definitions differ.

Specifically, all agree that a “major” bleeding event is one that is fatal, involves bleeding into a major organ, or leads to a substantial decline in hemoglobin level. However, the Thrombolysis in Myocardial Infarction trials use a decline of more than 5 g/dL in their definition,^23,25 while the International Society on Thrombosis and Haemostasis uses 2 g/dL.²⁴

Here, we review the clinical impact of the most common sources of anticoagulation-related hemorrhage—gastrointestinal, soft tissue, and urinary tract²⁶—as well as intracerebral hemorrhage, a less common but more uniformly devastating event.²⁷

Clinical impact of gastrointestinal hemorrhage

Each year, about 4.5% of patients taking warfarin have a gastrointestinal hemorrhage, though not all of these events are major.²⁸ Evolving data suggest that the newer agents (particularly dabigatran, rivaroxaban, and edoxaban) pose a higher risk of gastrointestinal bleeding than warfarin.²⁹ Patients may need plasma and blood transfusions and intravenous phytonadione, all of which carry risks, albeit small.

Frequently, endoscopy is needed to find the source of bleeding and to control it. If this does not work, angiographic intervention to infuse vasoconstrictors or embolic coils into the culprit artery may be required, and some patients need surgery. Each intervention carries its own risk.

Clinical impact of soft-tissue hemorrhage

Soft-tissue hemorrhage accounts for more than 20% of warfarin-related bleeding events²⁶; as yet, we know of no data on the rate with the new drugs. Soft-tissue hemorrhage is often localized to the large muscles of the retroperitoneum and legs. Though retroperitoneal hemorrhage accounts for a relatively small portion of soft-tissue hemorrhages, it is associated with high rates of morbidity and death and will therefore be our focus.²⁶

Some indications for anticoagulation pose a higher risk of thromboembolism than others

Much of the clinical impact of retroperitoneal hemorrhage is from a mass effect that causes abdominal compartment syndrome, hydroureter, ileus, abscess formation, and acute and chronic pain. At least 20% of cases are associated with femoral neuropathy. It can also lead to deep vein thrombosis from venous compression, coupled with hypercoagulability in response to bleeding. Brisk bleeding can lead to shock and death, and the mortality rate in retroperitoneal hemorrhage is estimated at 20% or higher.³⁰

In many cases, the retroperitoneal hemorrhage will self-tamponade and the blood will be reabsorbed once the bleeding has stopped, but uncontrolled bleeding may require surgical or angiographic intervention.³⁰

Clinical impact of urinary tract hemorrhage

Gross or microscopic hematuria can be found in an estimated 2% to 24% of patients taking warfarin^31–33; data are lacking for the target-specific oral anticoagulants. Interventions required to manage urinary tract bleeding include bladder irrigation and, less often, transfusion.³¹ Since a significant number of cases of hematuria are due to neoplastic disease,³² a diagnostic workup with radiographic imaging of the upper tract and cystoscopy of the lower tract is usually required.³¹ While life-threatening hemorrhage is uncommon, complications such as transient urinary obstruction from clots may occur.

Clinical impact of intracranial hemorrhage

Intracranial hemorrhage is the most feared and deadly of the bleeding complications of anticoagulation. The incidence in patients on warfarin is estimated at 2% to 3% per year, which is markedly higher than the estimated incidence of 25 per 100,000 person-years in the general population.³⁴ Emerging data indicate that the newer drugs are also associated with a risk of intracranial hemorrhage, though the risk is about half that with vitamin K antagonists.³⁵ Intracranial hemorrhage leads to death or disability in 76% of cases, compared with 3% of cases of bleeding from the gastrointestinal or urinary tract.²⁷

Regardless of the source of bleeding, hospitalization is likely to be required and may be  prolonged, with attendant risks of nosocomial harms such as infection.

Risk of rebleeding

Given the scope and severity of anticoagulation-related bleeding, there is strong interest in predicting and preventing it. By some estimates, the incidence of recurrent bleeding after resuming vitamin K antagonists is 8% to 13%.²² Although there are several indices for predicting the risk of major bleeding when starting anticoagulation, there are currently no validated tools to estimate a patient’s risk of rebleeding.³⁶

The patient factor that most consistently predicts major bleeding is a history of bleeding, particularly from the gastrointestinal tract. Finding and controlling the source of bleeding is important.^26,37 For example, a patient with gross hematuria who is found on cystoscopy to have a urothelial papilloma is unlikely to have rebleeding if the tumor is successfully resected and serial follow-up shows no regrowth. In contrast, consider a patient with a major gastrointestinal hemorrhage, the source of which remains elusive after upper, lower, and capsule endoscopy or, alternatively, is suspected to be from one of multiple angiodysplastic lesions. Without definitive source management, this patient faces a high risk of rebleeding.

With or without anticoagulation, after a first intracranial hemorrhage the risk of another one is estimated at 2% to 4% per year.³⁴ An observational study found a recurrence rate of 7.5% when vitamin K antagonist therapy was started after an intracranial hemorrhage (though not all patients were on a vitamin K antagonist at the time of the first hemorrhage).³⁸

Evolving data suggest the newer oral agents pose a higher risk of GI bleeding

Patients with lobar hemorrhage and those with suspected cerebral amyloid angiopathy may be at particularly high risk if anticoagulation is resumed. Conversely, initial events attributed to uncontrolled hypertension that subsequently can be well controlled may portend a lower risk of rebleeding.³⁴ For other types of intracranial hemorrhage, recurrence rates can be even higher. Irrespective of anticoagulation, one prospective study estimated the crude annual rebleeding rate with untreated arteriovenous malformations to be 7%.³⁹ In chronic subdural hematoma, the recurrence rate after initial drainage has been estimated at 9.2% to 26.5%, with use of anticoagulants (in this case, vitamin K antagonists) being an independent predictor of recurrence.⁴⁰

WHAT OTHER PATIENT FACTORS NEED CONSIDERATION?

Target INR on warfarin

An important factor influencing the risk of bleeding with warfarin is the intensity of this therapy.³⁷ A meta-analysis⁴¹ found that the risks of major hemorrhage and thromboembolism are minimized if the goal international normalized ratio (INR) is 2.0 to 3.0. When considering resuming anticoagulation after bleeding, make sure the therapeutic target is appropriate.³⁷

Table 3 summarizes recommended therapeutic ranges for frequently encountered indications for warfarin.^36,42,43

INR at time of the event and challenges in controlling it

The decision to resume anticoagulation in patients who bled while using warfarin must take into account the actual INR at the time of the event.

For example, consider a patient whose INR values are consistently in the therapeutic range.  While on vacation, he receives ciprofloxacin for acute prostatitis from an urgent care team, and no adjustment to INR monitoring or warfarin dose is made. Several days later, he presents with lower gastrointestinal bleeding. His INR is 8, and colonoscopy reveals diverticulosis with a bleeding vessel, responsive to endoscopic therapy. After controlling the source of bleeding and reinforcing the need to always review new medications for potential interactions with anticoagulation, it is reasonable to expect that he once again will be able to keep his INR in the therapeutic range.

A patient on anticoagulation for the same indication but who has a history of repeated supratherapeutic levels, poor adherence, or poor access to INR monitoring poses very different concerns about resuming anticoagulation (as well as which agent to use, as we discuss below).

Of note, a high INR alone does not explain bleeding. It is estimated that a workup for gastrointestinal bleeding and gross hematuria uncovers previously undetected lesions in approximately one-third of cases involving warfarin.²⁶ A similar malignancy-unmasking effect is now recognized in patients using the target-specific oral agents who experience gastrointestinal bleeding.⁴⁴ Accordingly, we recommend a comprehensive source evaluation for any anticoagulation-related hemorrhage.

Comorbid conditions

Comorbid conditions associated with bleeding include cancer, end-stage renal disease, liver disease, arterial hypertension, prior stroke, and alcohol abuse.^37,45 Gait instability, regardless of cause, may also increase the risk of trauma-related hemorrhage, but some have estimated that a patient would need to fall multiple times per week to contraindicate anticoagulation on the basis of falls alone.⁴⁶

Concurrent medications

Concomitant therapies, including antiplatelet drugs and nonsteroidal anti-inflammatory drugs, increase bleeding risk.^47,48 Aspirin and the nonsteroidals, in addition to having antiplatelet effects, also can cause gastric erosion.³⁷ In evaluating whether and when to restart anticoagulation, it is advisable to review the role that concomitant therapies may have had in the index bleeding event and to evaluate the risks and benefits of these other agents.

The factor that most consistently predicts major bleeding is a history of bleeding, particularly gastrointestinal bleeding

Additionally, warfarin has many interactions. Although the newer drugs are lauded for having fewer interactions, they are not completely free of them, and the potential for interactions must always be reviewed.⁴⁹ Further, unlike warfarin therapy, therapy with the newer agents is not routinely monitored with laboratory tests, so toxicity (or underdosing) may not be recognized until an adverse clinical event occurs. Ultimately, it may be safer to resume anticoagulation after a contributing drug can be safely discontinued.

Advanced age

The influence that the patient’s age should have on the decision to restart anticoagulation is unclear. Although the risk of intracranial hemorrhage increases with age, particularly after age 80, limited data exist in this population, particularly with regard to rebleeding. Further, age is a major risk factor for most thrombotic events, including venous thromboembolism and stroke from atrial fibrillation, so although the risks of anticoagulation may be higher, the benefits may also be higher than in younger patients.^37,46 We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage.

HOW LONG SHOULD WE WAIT TO RESTART ANTICOAGULATION?

We lack conclusive data on how long to wait to restart anticoagulation after an anticoagulation-associated hemorrhage.

The decision is complicated by evidence suggesting a rebound effect, with an increased risk of pulmonary embolism and atrial fibrillation-related stroke during the first 90 days of interruption of therapy with warfarin as well as with target-specific oral anticoagulants.^3–8 In anticoagulation-associated retroperitoneal bleeding, there is increased risk of deep vein thrombosis from compression, even if venous thromboembolism was not the initial indication for anticoagulation.³⁰

In patients with intracranial hemorrhage, evidence suggests that the intracranial hemorrhage itself increases the risk of arterial and venous thromboembolic events. Irrespective of whether a patient was previously on anticoagulation, the risk of arterial and venous thromboembolic events approaches 7% during the initial intracranial hemorrhage-related hospitalization and 9% during the first 90 days.^34,50,51

To date, the only information we have about when to resume anticoagulation comes from patients taking vitamin K antagonists.

Timing after gastrointestinal bleeding

Small case series suggest that in the first 2 months after warfarin-associated gastrointestinal bleeding, there is substantial risk of rebleeding when anticoagulation is resumed—and of thrombosis when it is not.^52,53 Two retrospective cohort studies may provide some guidance in this dilemma.^28,54

A workup for GI bleeding and gross hematuria uncovers previously undetected lesions in about one-third of cases involving warfarin

Witt et al²⁸ followed 442 patients who presented with gastrointestinal bleeding from any site during warfarin therapy for varied indications for up to 90 days after the index bleeding event. The risk of death was three times lower in patients who restarted warfarin than in those who did not, and their rate of thrombotic events was 10 times lower. The risk of recurrent gastrointestinal bleeding was statistically insignificant, and there were no fatal bleeding events. Anticoagulant therapy was generally resumed within 1 week of the bleeding event, at a median of 4 days.^28,55

Qureshi et al⁵⁴ performed a retrospective cohort study of 1,329 patients with  nonvalvular atrial fibrillation who had experienced a gastrointestinal hemorrhage while taking warfarin. They found that resuming warfarin after 7 days was not associated with a higher risk of recurrent gastrointestinal bleeding and that the rates of death and thromboembolism were lower than in patients who resumed warfarin after 30 days. On the other hand, the risk of recurrent gastrointestinal bleeding was significantly greater if therapy was resumed within the first week.

In view of these studies, we believe that most patients should resume anticoagulation after 4 to 7 days of interruption after gastrointestinal bleeding.⁵⁵

Timing after soft-tissue hemorrhage

The literature on resuming anticoagulation after soft-tissue hemorrhage is sparse. A retrospective study⁵² looked at this question in patients with spontaneous rectal sheath hematoma who had been receiving  antiplatelet drugs, intravenous heparin, vitamin K antagonists, or a combination of these, but not target-specific agents. More than half of the patients were on vitamin K antagonists at the time of hemorrhage. Analysis suggested that when benefits of resuming anticoagulation are believed to outweigh risks, it is reasonable to resume anticoagulation 4 days after the index event.⁵⁶

Timing after intracranial hemorrhage

Anticoagulation should not be considered within the first 24 hours after intracranial hemorrhage, as over 70% of patients develop some amount of hematoma expansion during this time.^34,57 The period thereafter poses a challenge, as the risk of hematoma expansion decreases while the risk of arterial and venous thromboembolism is ongoing and cumulative.⁵⁰

Perhaps surprisingly, national guidelines suggest starting prophylactic-dosed anticoagulation early in all intracranial hemorrhage patients, including those not previously on warfarin.^58,59 In a randomized trial, Boeer et al⁶⁰ concluded that starting low-dose subcutaneous heparin the day after an intracranial hemorrhage decreased the risk of thromboembolism without increasing the risk of rebleeding.⁶⁰ Dickmann et al⁶¹ similarly concluded that there was no increased risk of rebleeding with early prophylactic-dosed subcutaneous heparin.⁶¹ Optimal mechanical thromboprophylaxis, including graduated compression stockings and intermittent pneumatic compression stockings, is also encouraged.³⁴

We discourage using age alone as a reason to withhold anticoagulation after a hemorrhage

Expert opinion remains divided on when and if anticoagulants should be resumed.^34,62 The American Heart Association suggests that in nonvalvular atrial fibrillation, long-term anticoagulation should be avoided after spontaneous lobar hemorrhage; antiplatelet agents can be considered instead.⁵⁸ In nonlobar hemorrhage, the American Heart Association suggests that anticoagulation be considered, depending on strength of indication, 7 to 10 days after the onset.⁵⁸ The European Stroke Initiative suggests patients with strong indications for anticoagulation be restarted on warfarin 10 to 14 days after the event, depending on the risk of thromboembolism and recurrent intracranial hemorrhage.⁵⁹ Others suggest delaying resumption to 10 to 30 weeks after an index intracranial hemorrhage.⁶³

Overall, in the immediate acute period of intracranial hemorrhage, most patients will likely benefit from acute reversal of anticoagulation, followed by institution of prophylactic-dose anticoagulation after the first 24 hours. Going forward, patients who remain at higher risk of a recurrence of anticoagulant-related intracranial hemorrhage (such as those with lobar hemorrhage, suspected cerebral amyloid angiopathy, and other high-risk factors) than of thromboembolic events may be best managed without anticoagulants. Alternatively, patients with deep hemispheric intracranial hemorrhage, hypertension that can be well controlled, and a high risk of serious thromboembolism may experience net benefit from restarting anticoagulation.³⁴

We recommend considering restarting anticoagulation 7 days after the onset of intracranial hemorrhage in patients at high risk of thromboembolism and after at least 14 days for patients at lower risk (Table 2). Discussions with neurologic and neurosurgical consultants should also inform this timing decision.

WOULD A NEWER DRUG BE A BETTER CHOICE?

The emergence of target-specific oral anticoagulants, including factor Xa inhibitors such as rivaroxaban, apixaban, and edoxaban and the direct thrombin inhibitor dabigatran etexilate, presents further challenges in managing anticoagulation after hemorrhage. Table 4 summarizes the current FDA-approved indications.^64–67

These newer agents are attractive because, compared with warfarin, they have wider therapeutic windows, faster onset and offset of action, and fewer drug and food interactions.⁶⁸ A meta-analysis of data available to date suggests that the new drugs, compared with warfarin, show a favorable risk-benefit profile with reductions in stroke, intracranial hemorrhage, and mortality with similar overall major bleeding rates, except for a possible increase in gastrointestinal bleeding.⁶⁸

However, when managing anticoagulation after a bleeding event, the newer agents are challenging for two reasons: they may be associated with a higher incidence of gastrointestinal bleeding than warfarin, and they lack the typical reversal agents that can be used to manage an acute bleeding event.^68,69

In individual studies comparing warfarin with dabigatran,⁷⁰ rivaroxaban,⁷¹ apixaban,⁷² or edoxaban⁷³ for stroke prevention in patients with atrial fibrillation, there was no significant difference in the rate of major bleeding between dabigatran in its higher dose (150 mg twice a day) or rivaroxaban compared with warfarin.^70,71 The risk of major bleeding was actually lower with apixaban⁷² and edoxaban.⁷³

In regard to specific types of major bleeding, the rate of intracranial hemorrhage was significantly lower with dabigatran, rivaroxaban, apixaban, and edoxaban than with warfarin.^35,68–73 Some have proposed that since the brain is high in tissue factor, inhibition of tissue factor-factor VIIa complexes by vitamin K antagonists leaves the brain vulnerable to hemorrhage. Others suggest that the targeted mechanism of target-specific agents, as opposed to the multiple pathways in both the intrinsic and extrinsic coagulation cascade that vitamin K antagonists affect, may explain this difference.^35,74,75

However, some studies suggest that rivaroxaban and the higher doses of dabigatran and edoxaban are associated with higher rates of major gastrointestinal bleeding compared with warfarin.^69–71,76 But apixaban demonstrated no significant difference in gastrointestinal bleeding, and instead demonstrated rates of gastrointestinal bleeding comparable to that with aspirin for stroke prevention in atrial fibrillation.⁷²

The new oral anticoagulants lack antidotes or reversal agents such as phytonadione and fresh-frozen plasma that are available to manage warfarin-associated bleeding events. Other proposed reversal options for the new agents include activated charcoal (if the drugs were taken recently enough to remain in the gastrointestinal tract) and concentrated clotting factor product, though research is ongoing in regards to the most appropriate use in clinical practice.^37,69 Unlike rivaroxaban and apixaban, dabigatran has low plasma protein binding and is dialyzable, which provides another strategy in managing dabigatran-related bleeding.⁶⁹

We believe most patients should resume anticoagulation after 4 to 7 days of interruption after GI bleeding

Of note, the above bleeding risk calculations relate to the first anticoagulant-related bleeding event, though presumably the same risk comparison across agents may be applicable to rebleeding events. Given the data above, when anticoagulation is to be resumed after an intracranial hemorrhage, the risk of rebleeding, particularly in the form of recurrent intracranial hemorrhage, may be lower if a target-specific oral anticoagulant is used.⁷⁵ Similarly, when anticoagulation is to be resumed after a gastrointestinal bleeding event, reinitiation with warfarin or apixaban therapy may present the lowest risk of recurrent gastrointestinal rebleeding. In other sources of bleeding, such as retroperitoneal bleeding, we suggest consideration of transitioning to warfarin, given the availability of reversal agents in the event of recurrent bleeding.

Other important drug-specific factors that must be noted when selecting an agent with which to resume anticoagulation after a hemorrhage include the following:

• In patients with significant renal impairment, the choice of agent will be limited to a vitamin K antagonist.⁷⁷
• A meta-analysis of randomized clinical trials suggests that in the elderly (age 75 and older) target-specific oral anticoagulants did not cause excess bleeding and were associated with at least equal efficacy compared with vitamin K antagonists.⁷⁸
• Target-specific oral anticoagulants may be beneficial in patients who have challenges in achieving INR targets, as evidence suggests that switching to them is associated with a reduction in bleeding for patients who struggle to maintain an appropriately therapeutic INR.⁶⁸ On the other hand, if there is concern that a patient may occasionally miss doses of an anticoagulant, given the rapid onset and offset of action of target-specific agents compared with warfarin, a missed dose of a target-specific agent may result in faster dissolution of anticoagulant effect and increased risk of thrombotic events, and lapses in anticoagulation will not be identified by routine drug monitoring.^6–8,75 As such, it is vital to have a frank discussion with any patient who has difficulty maintaining therapeutic INRs on warfarin treatment to make sure that he or she is not missing doses.
• If there is no clear and compelling reason to select a particular agent, cost considerations should be taken into account. We have included estimated 30-day pricing for the various agents in Table 4. 

Intraneural ganglion cysts of peripheral nerves occurring within the epineural sheath are rare.^1-7 Case reports exist primarily within the neurosurgical literature, but very little in the orthopedic literature describes this condition. The peripheral nerve most commonly affected by an intraneural ganglion is the common peroneal nerve (CPN).^2,8,9 Such ganglia most often afflict middle-aged men with a history of micro- or macro-trauma and present with typical clinical manifestations of calf pain and progressive symptoms of ipsilateral foot drop and lower leg paresthesia.^2-5,10-12 The mechanism by which these ganglia form is not well understood and, as a result, treatment options are debated.⁶ Recent development of a “unified articular theory,” suggests that such intraneural ganglia of the CPN are fed by a small, recurrent articular branch of the CPN.^6,12,13 Cadaveric studies indicate that this branch originates from the deep peroneal nerve, just millimeters distal to the bifurcation of the CPN, and extends to the superior tibiofibular joint, providing direct access for cyst fluid to enter the CPN following the path of least resistance.^7,8,12,14 Therefore, according to the unified articular theory, the recommended treatment involves division of the articular branch, allowing the ganglion to be decompressed.⁶

We present a case of a 41-year-old man with an intraneural ganglion cyst of the CPN who was successfully treated, according to the recommendations of the unified articular theory. It is important for orthopedic surgeons to read about and recognize this condition, because knowledge of the operative technique outlined in our report allows it to be treated quite effectively. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 41-year-old man presented with a 2-month history of traumatic left lateral knee pain with numbness and weakness to the left foot and ankle. Initial examination showed a mild restriction of lumbosacral range of motion, with no complaints of lower back pain. Sciatic root stretch signs were negative. Strength testing of the lower extremities revealed 3+/5 strength of ankle dorsiflexion and great toe extension on the left side. There was a mild alteration in sensation to light touch on the lateral side of the left foot. Tenderness, without swelling, was present around the left fibular head. There was a positive Tinel sign over the peroneal nerve at the level of the fibular neck.

The patient was initially treated with anti-inflammatories and activity modification. An electromyogram (EMG)/nerve conduction study of the lower extremity showed a left peroneal nerve neurapraxia at the level of the fibular head. Noncontrast magnetic resonance imaging (MRI) of the left knee showed a “slightly prominent vein coursing posterior to the fibular head near the expected location of the common peroneal nerve,” according to the radiologist’s notes (Figure 1). The patient exhibited improvement with use of anti-inflammatories over several months. There was an increase in his ankle dorsiflexion strength to 4/5 and improvement in his pain and numbness.

Approximately 7 months after his initial presentation, the patient developed a marked worsening—increased numbness and weakness to ankle dorsiflexion—of his original symptoms. A repeat EMG/nerve conduction study of the lower extremity showed a persistent peroneal nerve neuropathy with a persistent denervation of the extensor hallucis longus, tibialis anterior, and extensor digitorum brevis muscles.

Because of continuing symptoms and increasing pain, the patient had surgery 8 months after his initial presentation. At that time, a markedly thickened peroneal nerve was identified. An incision in the epineural sheath released a clear gelatinous fluid consistent with a ganglion cyst. Through the epineural incision, the nerve was decompressed by manually “milking” the fluid from within the sheath. Approximately  30 mL of mucinous fluid was obtained and sent to pathology. No cells were identified.

Postoperatively, the patient noted a marked improvement in his pain. By 2 weeks postoperatively, the numbness in his foot had resolved. At 6 weeks after surgery, the strength of his tibialis anterior and extensor hallucis longus muscles had improved from 3+ to 4-, and he was free of pain.

At 2 months postoperatively, the patient redeveloped pain and numbness, and noted progressive weakness of his left foot and ankle. A repeat MRI of the left knee showed a dilated tubular structure corresponding to the course of the CPN. Comparison of this MRI with the initial MRI showed that the “prominent vein” was actually the dilated CPN.

He was taken to the operating room again 5 months after his first operation. At this time, the CPN was again noted to be markedly dilated (Figure 2). The nerve was explored and a recurrent branch to the proximal tibiofibular joint was identified and divided (Figures 3, 4). Through the divided branch, the CPN could be decompressed by manually “milking” the nerve in a proximal-to-distal direction, expressing clear gelatinous fluid consistent with a ganglion cyst (Figure 5). Pathology of the excised portion of the recurrent nerve was consistent with an intraneural ganglion cyst.

By 2 weeks postoperatively, the numbness of the patient’s left foot had completely resolved, as did his pain. By 3 months after surgery, his extensor hallucis longus strength was 5/5, and ankle dorsiflexion was 4-/5. At 6 months, his ankle dorsiflexion strength was 5/5, and he was completely asymptomatic. At 2 years postoperatively, he remained completely asymptomatic. A follow-up MRI of the left knee showed a ganglion cyst present at the proximal tibiofibular joint with resolution of the intraneural ganglion cyst within the CPN (Figure 6).

Discussion

Intraneural ganglia of peripheral nerves are relatively rare, most commonly occurring in the CPN.^6,8,9 A literature search reveals that this condition is only sparsely reported in orthopedic journals. This report, therefore, describes this rare, yet curable, condition. As noted, without appropriate intervention, the condition has a high likelihood of recurrence with only a brief interruption of symptoms.^6,8,9,12

The operative technique delineated in this report relies heavily on research demonstrating that peroneal intraneural ganglia develop from the superior tibiofibular joint and gain access to the CPN via the recurrent articular branch.^8,13 Research indicates that such ganglia preferentially proceed proximally along the deep portion of the CPN, within the epineurium.⁶ This hypothesis was corroborated in our case by the swollen appearance of the CPN proximal to its bifurcation.

Currently, there is no consensus on treatment of intraneural ganglion cysts of the CPN. However, evidence suggests that disconnection of the recurrent branch of the CPN may be important in successfully treating the condition.^6,9,14 This unified articular theory was initially proposed by Spinner and colleagues¹² in 2003 and recommends that surgical treatment focus on the articular branch as the source of cyst fluid.^6,9,12,14 This theory by Spinner and coauthors^12,14 was substantiated in our case: Once the articular branch was disconnected, cyst fluid was easily expressed via antegrade massage through the disconnected end. Pathologic analysis of a portion of the detached articular branch is also recommended to rule out other cystic lesions, such as cystic shwannomas.¹⁴

The history of the unified articular theory began in the mid-1990s, when Dr. Robert Spinner, board certified in both orthopedic and neurologic surgery, began researching causes of intraneural ganglion cysts. At the time, such ganglia were often treated by radical resection of the nerve and the cyst. Based on his review of literature, and his own cases, Spinner¹⁵ developed the theory that, just as with extraneural ganglia, these cysts are fed by fluid from the joint. According to Spinner,⁹ the sources of such connections were very small articular nerve branches that connect the nerve to the joint. His research led him to the original citation of such an intraneural ganglion of the ulnar nerve, first described by Dr. M. Beauchene, a French physician, in 1810.¹⁶ Spinner also discovered that Beauchene’s original dissection specimen had been preserved and was displayed in a medical museum in Paris. When Spinner went to France to view the specimen, he indeed found an intraneural ganglion of the ulnar nerve. On closer inspection, Spinner also discovered a small articular nerve branch containing a “hollow lumen” that would have been capable of allowing the passage of fluid into the nerve and leading to the development of a cyst.¹⁶

In our case, in the first operation, a simple incisional decompression of the CPN was performed. Unfortunately, the ganglion cyst quickly recurred, as did the patient’s symptoms. In the second surgical procedure, the articular branch connecting the peroneal nerve to the proximal tibiofibular joint was incised and disconnected from the nerve. This allowed the nerve to be decompressed and prevented a recurrence of the ganglion cyst within the nerve with complete resolution of the patient’s symptoms. This difference alone most likely accounts for the rapid recurrence of symptoms after the initial operation, since the fluid was simply drained, but the source was not detached, allowing the ganglion to recur.^6,12,14 This is similar in theory to excising the attachment of a ganglion cyst at the wrist from the underlying joint capsule rather than performing a needle aspiration or puncturing of the cyst.¹²

Regarding the imaging techniques used to identify intraneural ganglia, it is essential that the surgeon be aware of the unified articular theory and the likely presence of an articular branch. Such branches are extremely small and may be easily missed on imaging and intraoperatively.^17,18 MRI is the best method to image these cysts because of its superior ability to visualize soft-tissue lesions.^18,19 Intraneural ganglion cysts typically appear as homogenous, lobulated, well-circumscribed masses that are hyperintense on T2-weighted MRI.^3,19 Gadolinium may also offer diagnostic utility, because these masses do not enhance with its use on T1-weighted MRI.^3,17,19 By employing these techniques, one may easily view most of the ganglion cyst. To image the small articular branch, Spinner and colleagues¹⁷ recommend thin-section images with high–spatial resolution T2-imaging. They also advocate obtaining multiple image views and planes to increase the likelihood of successful imaging.¹⁷ 

The applications of the unified articular theory also extend beyond intraneural ganglia of the CPN. While the CPN is the most common location for intraneural ganglion occurrence,^6,17,20 cases have also been described of intraneural ganglion cysts of the tibial nerve at the proximal tibiofibular joint, as well as via the posterior tibial and medial plantar nerves at the subtalar joint within the tarsal tunnel.^11,18-23 Most cases involving the posterior tibial and medial plantar nerves were found in patients presenting with signs of tarsal tunnel syndrome.^22,23 Intraneural ganglia have also been found within the superficial peroneal nerve arising from the inferior tibiofibular joint.²⁰ In certain cases, these ganglia have also been noted to connect to the joint via a small articular branch.^19,22 In 1 case of an intraneural ganglion of the tibial nerve at the superior tibiofibular joint, initial conservative surgery led to early recurrence of symptoms.¹⁹ Just as in our case, the patient returned to the operating room and, after isolation and ligation of an articular branch, the patient experienced long-term resolution of both the symptoms and the cyst.¹⁹

Given the overwhelming evidence in support of the unified articular theory, we agree with the recommendation by Spinner and colleagues¹⁹ to search for an articular branch both via preoperative imaging and during the operation itself in all cases of intraneural ganglia. Assuming the mechanism of cyst formation is the same in most cases of intraneural ganglia, one could reasonably apply the same surgical techniques used in our case to the management of all intraneural ganglia, drastically reducing recurrence rates.

Conclusion

Based on research and corroborated by this case, the key to successful operative treatment of a common peroneal intraneural ganglion is division of the recurrent articular branch, which connects the proximal tibiofibular joint to the CPN.^6,9,11,12,14 Evidence has shown that disconnecting the articular branch and disrupting the source of the intraneural ganglion can resolve the condition and dramatically diminish the chance of recurrence.^6,8,12,14 This has become known as the unified articular theory.^6,12,14 Reports also suggest that, without disconnecting this articular branch, intraneural ganglion recurrence rates may be higher than 30%.^6,12,14,19 This case, therefore, supports the findings of previous authors^9-11,14 and provides an example of successful utilization of the treatment protocol delineated by Spinner and colleagues.^10,11

Intraneural ganglion cysts of peripheral nerves occurring within the epineural sheath are rare.^1-7 Case reports exist primarily within the neurosurgical literature, but very little in the orthopedic literature describes this condition. The peripheral nerve most commonly affected by an intraneural ganglion is the common peroneal nerve (CPN).^2,8,9 Such ganglia most often afflict middle-aged men with a history of micro- or macro-trauma and present with typical clinical manifestations of calf pain and progressive symptoms of ipsilateral foot drop and lower leg paresthesia.^2-5,10-12 The mechanism by which these ganglia form is not well understood and, as a result, treatment options are debated.⁶ Recent development of a “unified articular theory,” suggests that such intraneural ganglia of the CPN are fed by a small, recurrent articular branch of the CPN.^6,12,13 Cadaveric studies indicate that this branch originates from the deep peroneal nerve, just millimeters distal to the bifurcation of the CPN, and extends to the superior tibiofibular joint, providing direct access for cyst fluid to enter the CPN following the path of least resistance.^7,8,12,14 Therefore, according to the unified articular theory, the recommended treatment involves division of the articular branch, allowing the ganglion to be decompressed.⁶

We present a case of a 41-year-old man with an intraneural ganglion cyst of the CPN who was successfully treated, according to the recommendations of the unified articular theory. It is important for orthopedic surgeons to read about and recognize this condition, because knowledge of the operative technique outlined in our report allows it to be treated quite effectively. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 41-year-old man presented with a 2-month history of traumatic left lateral knee pain with numbness and weakness to the left foot and ankle. Initial examination showed a mild restriction of lumbosacral range of motion, with no complaints of lower back pain. Sciatic root stretch signs were negative. Strength testing of the lower extremities revealed 3+/5 strength of ankle dorsiflexion and great toe extension on the left side. There was a mild alteration in sensation to light touch on the lateral side of the left foot. Tenderness, without swelling, was present around the left fibular head. There was a positive Tinel sign over the peroneal nerve at the level of the fibular neck.

The patient was initially treated with anti-inflammatories and activity modification. An electromyogram (EMG)/nerve conduction study of the lower extremity showed a left peroneal nerve neurapraxia at the level of the fibular head. Noncontrast magnetic resonance imaging (MRI) of the left knee showed a “slightly prominent vein coursing posterior to the fibular head near the expected location of the common peroneal nerve,” according to the radiologist’s notes (Figure 1). The patient exhibited improvement with use of anti-inflammatories over several months. There was an increase in his ankle dorsiflexion strength to 4/5 and improvement in his pain and numbness.

Approximately 7 months after his initial presentation, the patient developed a marked worsening—increased numbness and weakness to ankle dorsiflexion—of his original symptoms. A repeat EMG/nerve conduction study of the lower extremity showed a persistent peroneal nerve neuropathy with a persistent denervation of the extensor hallucis longus, tibialis anterior, and extensor digitorum brevis muscles.

Because of continuing symptoms and increasing pain, the patient had surgery 8 months after his initial presentation. At that time, a markedly thickened peroneal nerve was identified. An incision in the epineural sheath released a clear gelatinous fluid consistent with a ganglion cyst. Through the epineural incision, the nerve was decompressed by manually “milking” the fluid from within the sheath. Approximately  30 mL of mucinous fluid was obtained and sent to pathology. No cells were identified.

Postoperatively, the patient noted a marked improvement in his pain. By 2 weeks postoperatively, the numbness in his foot had resolved. At 6 weeks after surgery, the strength of his tibialis anterior and extensor hallucis longus muscles had improved from 3+ to 4-, and he was free of pain.

At 2 months postoperatively, the patient redeveloped pain and numbness, and noted progressive weakness of his left foot and ankle. A repeat MRI of the left knee showed a dilated tubular structure corresponding to the course of the CPN. Comparison of this MRI with the initial MRI showed that the “prominent vein” was actually the dilated CPN.

He was taken to the operating room again 5 months after his first operation. At this time, the CPN was again noted to be markedly dilated (Figure 2). The nerve was explored and a recurrent branch to the proximal tibiofibular joint was identified and divided (Figures 3, 4). Through the divided branch, the CPN could be decompressed by manually “milking” the nerve in a proximal-to-distal direction, expressing clear gelatinous fluid consistent with a ganglion cyst (Figure 5). Pathology of the excised portion of the recurrent nerve was consistent with an intraneural ganglion cyst.

By 2 weeks postoperatively, the numbness of the patient’s left foot had completely resolved, as did his pain. By 3 months after surgery, his extensor hallucis longus strength was 5/5, and ankle dorsiflexion was 4-/5. At 6 months, his ankle dorsiflexion strength was 5/5, and he was completely asymptomatic. At 2 years postoperatively, he remained completely asymptomatic. A follow-up MRI of the left knee showed a ganglion cyst present at the proximal tibiofibular joint with resolution of the intraneural ganglion cyst within the CPN (Figure 6).

Discussion

Intraneural ganglia of peripheral nerves are relatively rare, most commonly occurring in the CPN.^6,8,9 A literature search reveals that this condition is only sparsely reported in orthopedic journals. This report, therefore, describes this rare, yet curable, condition. As noted, without appropriate intervention, the condition has a high likelihood of recurrence with only a brief interruption of symptoms.^6,8,9,12

The operative technique delineated in this report relies heavily on research demonstrating that peroneal intraneural ganglia develop from the superior tibiofibular joint and gain access to the CPN via the recurrent articular branch.^8,13 Research indicates that such ganglia preferentially proceed proximally along the deep portion of the CPN, within the epineurium.⁶ This hypothesis was corroborated in our case by the swollen appearance of the CPN proximal to its bifurcation.

Currently, there is no consensus on treatment of intraneural ganglion cysts of the CPN. However, evidence suggests that disconnection of the recurrent branch of the CPN may be important in successfully treating the condition.^6,9,14 This unified articular theory was initially proposed by Spinner and colleagues¹² in 2003 and recommends that surgical treatment focus on the articular branch as the source of cyst fluid.^6,9,12,14 This theory by Spinner and coauthors^12,14 was substantiated in our case: Once the articular branch was disconnected, cyst fluid was easily expressed via antegrade massage through the disconnected end. Pathologic analysis of a portion of the detached articular branch is also recommended to rule out other cystic lesions, such as cystic shwannomas.¹⁴

The history of the unified articular theory began in the mid-1990s, when Dr. Robert Spinner, board certified in both orthopedic and neurologic surgery, began researching causes of intraneural ganglion cysts. At the time, such ganglia were often treated by radical resection of the nerve and the cyst. Based on his review of literature, and his own cases, Spinner¹⁵ developed the theory that, just as with extraneural ganglia, these cysts are fed by fluid from the joint. According to Spinner,⁹ the sources of such connections were very small articular nerve branches that connect the nerve to the joint. His research led him to the original citation of such an intraneural ganglion of the ulnar nerve, first described by Dr. M. Beauchene, a French physician, in 1810.¹⁶ Spinner also discovered that Beauchene’s original dissection specimen had been preserved and was displayed in a medical museum in Paris. When Spinner went to France to view the specimen, he indeed found an intraneural ganglion of the ulnar nerve. On closer inspection, Spinner also discovered a small articular nerve branch containing a “hollow lumen” that would have been capable of allowing the passage of fluid into the nerve and leading to the development of a cyst.¹⁶

In our case, in the first operation, a simple incisional decompression of the CPN was performed. Unfortunately, the ganglion cyst quickly recurred, as did the patient’s symptoms. In the second surgical procedure, the articular branch connecting the peroneal nerve to the proximal tibiofibular joint was incised and disconnected from the nerve. This allowed the nerve to be decompressed and prevented a recurrence of the ganglion cyst within the nerve with complete resolution of the patient’s symptoms. This difference alone most likely accounts for the rapid recurrence of symptoms after the initial operation, since the fluid was simply drained, but the source was not detached, allowing the ganglion to recur.^6,12,14 This is similar in theory to excising the attachment of a ganglion cyst at the wrist from the underlying joint capsule rather than performing a needle aspiration or puncturing of the cyst.¹²

Regarding the imaging techniques used to identify intraneural ganglia, it is essential that the surgeon be aware of the unified articular theory and the likely presence of an articular branch. Such branches are extremely small and may be easily missed on imaging and intraoperatively.^17,18 MRI is the best method to image these cysts because of its superior ability to visualize soft-tissue lesions.^18,19 Intraneural ganglion cysts typically appear as homogenous, lobulated, well-circumscribed masses that are hyperintense on T2-weighted MRI.^3,19 Gadolinium may also offer diagnostic utility, because these masses do not enhance with its use on T1-weighted MRI.^3,17,19 By employing these techniques, one may easily view most of the ganglion cyst. To image the small articular branch, Spinner and colleagues¹⁷ recommend thin-section images with high–spatial resolution T2-imaging. They also advocate obtaining multiple image views and planes to increase the likelihood of successful imaging.¹⁷ 

The applications of the unified articular theory also extend beyond intraneural ganglia of the CPN. While the CPN is the most common location for intraneural ganglion occurrence,^6,17,20 cases have also been described of intraneural ganglion cysts of the tibial nerve at the proximal tibiofibular joint, as well as via the posterior tibial and medial plantar nerves at the subtalar joint within the tarsal tunnel.^11,18-23 Most cases involving the posterior tibial and medial plantar nerves were found in patients presenting with signs of tarsal tunnel syndrome.^22,23 Intraneural ganglia have also been found within the superficial peroneal nerve arising from the inferior tibiofibular joint.²⁰ In certain cases, these ganglia have also been noted to connect to the joint via a small articular branch.^19,22 In 1 case of an intraneural ganglion of the tibial nerve at the superior tibiofibular joint, initial conservative surgery led to early recurrence of symptoms.¹⁹ Just as in our case, the patient returned to the operating room and, after isolation and ligation of an articular branch, the patient experienced long-term resolution of both the symptoms and the cyst.¹⁹

Given the overwhelming evidence in support of the unified articular theory, we agree with the recommendation by Spinner and colleagues¹⁹ to search for an articular branch both via preoperative imaging and during the operation itself in all cases of intraneural ganglia. Assuming the mechanism of cyst formation is the same in most cases of intraneural ganglia, one could reasonably apply the same surgical techniques used in our case to the management of all intraneural ganglia, drastically reducing recurrence rates.

Conclusion

Based on research and corroborated by this case, the key to successful operative treatment of a common peroneal intraneural ganglion is division of the recurrent articular branch, which connects the proximal tibiofibular joint to the CPN.^6,9,11,12,14 Evidence has shown that disconnecting the articular branch and disrupting the source of the intraneural ganglion can resolve the condition and dramatically diminish the chance of recurrence.^6,8,12,14 This has become known as the unified articular theory.^6,12,14 Reports also suggest that, without disconnecting this articular branch, intraneural ganglion recurrence rates may be higher than 30%.^6,12,14,19 This case, therefore, supports the findings of previous authors^9-11,14 and provides an example of successful utilization of the treatment protocol delineated by Spinner and colleagues.^10,11

Intraneural ganglion cysts of peripheral nerves occurring within the epineural sheath are rare.^1-7 Case reports exist primarily within the neurosurgical literature, but very little in the orthopedic literature describes this condition. The peripheral nerve most commonly affected by an intraneural ganglion is the common peroneal nerve (CPN).^2,8,9 Such ganglia most often afflict middle-aged men with a history of micro- or macro-trauma and present with typical clinical manifestations of calf pain and progressive symptoms of ipsilateral foot drop and lower leg paresthesia.^2-5,10-12 The mechanism by which these ganglia form is not well understood and, as a result, treatment options are debated.⁶ Recent development of a “unified articular theory,” suggests that such intraneural ganglia of the CPN are fed by a small, recurrent articular branch of the CPN.^6,12,13 Cadaveric studies indicate that this branch originates from the deep peroneal nerve, just millimeters distal to the bifurcation of the CPN, and extends to the superior tibiofibular joint, providing direct access for cyst fluid to enter the CPN following the path of least resistance.^7,8,12,14 Therefore, according to the unified articular theory, the recommended treatment involves division of the articular branch, allowing the ganglion to be decompressed.⁶

We present a case of a 41-year-old man with an intraneural ganglion cyst of the CPN who was successfully treated, according to the recommendations of the unified articular theory. It is important for orthopedic surgeons to read about and recognize this condition, because knowledge of the operative technique outlined in our report allows it to be treated quite effectively. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 41-year-old man presented with a 2-month history of traumatic left lateral knee pain with numbness and weakness to the left foot and ankle. Initial examination showed a mild restriction of lumbosacral range of motion, with no complaints of lower back pain. Sciatic root stretch signs were negative. Strength testing of the lower extremities revealed 3+/5 strength of ankle dorsiflexion and great toe extension on the left side. There was a mild alteration in sensation to light touch on the lateral side of the left foot. Tenderness, without swelling, was present around the left fibular head. There was a positive Tinel sign over the peroneal nerve at the level of the fibular neck.

The patient was initially treated with anti-inflammatories and activity modification. An electromyogram (EMG)/nerve conduction study of the lower extremity showed a left peroneal nerve neurapraxia at the level of the fibular head. Noncontrast magnetic resonance imaging (MRI) of the left knee showed a “slightly prominent vein coursing posterior to the fibular head near the expected location of the common peroneal nerve,” according to the radiologist’s notes (Figure 1). The patient exhibited improvement with use of anti-inflammatories over several months. There was an increase in his ankle dorsiflexion strength to 4/5 and improvement in his pain and numbness.

Approximately 7 months after his initial presentation, the patient developed a marked worsening—increased numbness and weakness to ankle dorsiflexion—of his original symptoms. A repeat EMG/nerve conduction study of the lower extremity showed a persistent peroneal nerve neuropathy with a persistent denervation of the extensor hallucis longus, tibialis anterior, and extensor digitorum brevis muscles.

Because of continuing symptoms and increasing pain, the patient had surgery 8 months after his initial presentation. At that time, a markedly thickened peroneal nerve was identified. An incision in the epineural sheath released a clear gelatinous fluid consistent with a ganglion cyst. Through the epineural incision, the nerve was decompressed by manually “milking” the fluid from within the sheath. Approximately  30 mL of mucinous fluid was obtained and sent to pathology. No cells were identified.

Postoperatively, the patient noted a marked improvement in his pain. By 2 weeks postoperatively, the numbness in his foot had resolved. At 6 weeks after surgery, the strength of his tibialis anterior and extensor hallucis longus muscles had improved from 3+ to 4-, and he was free of pain.

At 2 months postoperatively, the patient redeveloped pain and numbness, and noted progressive weakness of his left foot and ankle. A repeat MRI of the left knee showed a dilated tubular structure corresponding to the course of the CPN. Comparison of this MRI with the initial MRI showed that the “prominent vein” was actually the dilated CPN.

He was taken to the operating room again 5 months after his first operation. At this time, the CPN was again noted to be markedly dilated (Figure 2). The nerve was explored and a recurrent branch to the proximal tibiofibular joint was identified and divided (Figures 3, 4). Through the divided branch, the CPN could be decompressed by manually “milking” the nerve in a proximal-to-distal direction, expressing clear gelatinous fluid consistent with a ganglion cyst (Figure 5). Pathology of the excised portion of the recurrent nerve was consistent with an intraneural ganglion cyst.

By 2 weeks postoperatively, the numbness of the patient’s left foot had completely resolved, as did his pain. By 3 months after surgery, his extensor hallucis longus strength was 5/5, and ankle dorsiflexion was 4-/5. At 6 months, his ankle dorsiflexion strength was 5/5, and he was completely asymptomatic. At 2 years postoperatively, he remained completely asymptomatic. A follow-up MRI of the left knee showed a ganglion cyst present at the proximal tibiofibular joint with resolution of the intraneural ganglion cyst within the CPN (Figure 6).

Discussion

Intraneural ganglia of peripheral nerves are relatively rare, most commonly occurring in the CPN.^6,8,9 A literature search reveals that this condition is only sparsely reported in orthopedic journals. This report, therefore, describes this rare, yet curable, condition. As noted, without appropriate intervention, the condition has a high likelihood of recurrence with only a brief interruption of symptoms.^6,8,9,12

The operative technique delineated in this report relies heavily on research demonstrating that peroneal intraneural ganglia develop from the superior tibiofibular joint and gain access to the CPN via the recurrent articular branch.^8,13 Research indicates that such ganglia preferentially proceed proximally along the deep portion of the CPN, within the epineurium.⁶ This hypothesis was corroborated in our case by the swollen appearance of the CPN proximal to its bifurcation.

Currently, there is no consensus on treatment of intraneural ganglion cysts of the CPN. However, evidence suggests that disconnection of the recurrent branch of the CPN may be important in successfully treating the condition.^6,9,14 This unified articular theory was initially proposed by Spinner and colleagues¹² in 2003 and recommends that surgical treatment focus on the articular branch as the source of cyst fluid.^6,9,12,14 This theory by Spinner and coauthors^12,14 was substantiated in our case: Once the articular branch was disconnected, cyst fluid was easily expressed via antegrade massage through the disconnected end. Pathologic analysis of a portion of the detached articular branch is also recommended to rule out other cystic lesions, such as cystic shwannomas.¹⁴

The history of the unified articular theory began in the mid-1990s, when Dr. Robert Spinner, board certified in both orthopedic and neurologic surgery, began researching causes of intraneural ganglion cysts. At the time, such ganglia were often treated by radical resection of the nerve and the cyst. Based on his review of literature, and his own cases, Spinner¹⁵ developed the theory that, just as with extraneural ganglia, these cysts are fed by fluid from the joint. According to Spinner,⁹ the sources of such connections were very small articular nerve branches that connect the nerve to the joint. His research led him to the original citation of such an intraneural ganglion of the ulnar nerve, first described by Dr. M. Beauchene, a French physician, in 1810.¹⁶ Spinner also discovered that Beauchene’s original dissection specimen had been preserved and was displayed in a medical museum in Paris. When Spinner went to France to view the specimen, he indeed found an intraneural ganglion of the ulnar nerve. On closer inspection, Spinner also discovered a small articular nerve branch containing a “hollow lumen” that would have been capable of allowing the passage of fluid into the nerve and leading to the development of a cyst.¹⁶

In our case, in the first operation, a simple incisional decompression of the CPN was performed. Unfortunately, the ganglion cyst quickly recurred, as did the patient’s symptoms. In the second surgical procedure, the articular branch connecting the peroneal nerve to the proximal tibiofibular joint was incised and disconnected from the nerve. This allowed the nerve to be decompressed and prevented a recurrence of the ganglion cyst within the nerve with complete resolution of the patient’s symptoms. This difference alone most likely accounts for the rapid recurrence of symptoms after the initial operation, since the fluid was simply drained, but the source was not detached, allowing the ganglion to recur.^6,12,14 This is similar in theory to excising the attachment of a ganglion cyst at the wrist from the underlying joint capsule rather than performing a needle aspiration or puncturing of the cyst.¹²

Regarding the imaging techniques used to identify intraneural ganglia, it is essential that the surgeon be aware of the unified articular theory and the likely presence of an articular branch. Such branches are extremely small and may be easily missed on imaging and intraoperatively.^17,18 MRI is the best method to image these cysts because of its superior ability to visualize soft-tissue lesions.^18,19 Intraneural ganglion cysts typically appear as homogenous, lobulated, well-circumscribed masses that are hyperintense on T2-weighted MRI.^3,19 Gadolinium may also offer diagnostic utility, because these masses do not enhance with its use on T1-weighted MRI.^3,17,19 By employing these techniques, one may easily view most of the ganglion cyst. To image the small articular branch, Spinner and colleagues¹⁷ recommend thin-section images with high–spatial resolution T2-imaging. They also advocate obtaining multiple image views and planes to increase the likelihood of successful imaging.¹⁷ 

The applications of the unified articular theory also extend beyond intraneural ganglia of the CPN. While the CPN is the most common location for intraneural ganglion occurrence,^6,17,20 cases have also been described of intraneural ganglion cysts of the tibial nerve at the proximal tibiofibular joint, as well as via the posterior tibial and medial plantar nerves at the subtalar joint within the tarsal tunnel.^11,18-23 Most cases involving the posterior tibial and medial plantar nerves were found in patients presenting with signs of tarsal tunnel syndrome.^22,23 Intraneural ganglia have also been found within the superficial peroneal nerve arising from the inferior tibiofibular joint.²⁰ In certain cases, these ganglia have also been noted to connect to the joint via a small articular branch.^19,22 In 1 case of an intraneural ganglion of the tibial nerve at the superior tibiofibular joint, initial conservative surgery led to early recurrence of symptoms.¹⁹ Just as in our case, the patient returned to the operating room and, after isolation and ligation of an articular branch, the patient experienced long-term resolution of both the symptoms and the cyst.¹⁹

Given the overwhelming evidence in support of the unified articular theory, we agree with the recommendation by Spinner and colleagues¹⁹ to search for an articular branch both via preoperative imaging and during the operation itself in all cases of intraneural ganglia. Assuming the mechanism of cyst formation is the same in most cases of intraneural ganglia, one could reasonably apply the same surgical techniques used in our case to the management of all intraneural ganglia, drastically reducing recurrence rates.

Conclusion

Based on research and corroborated by this case, the key to successful operative treatment of a common peroneal intraneural ganglion is division of the recurrent articular branch, which connects the proximal tibiofibular joint to the CPN.^6,9,11,12,14 Evidence has shown that disconnecting the articular branch and disrupting the source of the intraneural ganglion can resolve the condition and dramatically diminish the chance of recurrence.^6,8,12,14 This has become known as the unified articular theory.^6,12,14 Reports also suggest that, without disconnecting this articular branch, intraneural ganglion recurrence rates may be higher than 30%.^6,12,14,19 This case, therefore, supports the findings of previous authors^9-11,14 and provides an example of successful utilization of the treatment protocol delineated by Spinner and colleagues.^10,11

In this session, Drs. Michelle Mourad and Christopher Moriates took a systematic approach to answer quality questions that we commonly encounter in our hospitalist practice. They reviewed current evidence including meta-analyses and systematic reviews to arrive at an answer for various quality-related questions. These are summarized below:

1. What are the common features of interventions that have successfully reduced re-admissions? Effective interventions that enhance patient capacity to reliably access and engage in post-discharge care has been associated with success in decreasing re-admissions.

2. 

   Does patient engagement correlate with decreased resource use or readmissions? Patient activation is defined as knowledge, skills, confidence and inclination to assume responsibility for managing one’s own health. A higher patient activation score reduced the risk of 30-day hospital re-utilization.
3. Does patients’ report of their healthcare experience reflect quality of care? Patient satisfaction scores may be a reflection of their desires (for example, to get pain medications) regardless of clinical benefit. In these situations, quality should be based on achieving a mutual understanding of patient situation and treatment plan between the provider and patient.
4. Is there any relationship between quality of care and health outcomes? Positive associations were found between patient experience and safety/effectiveness. Including patient experience in quality improvement, therefore, may lead to improvements in safety and effectiveness. Reducing the trauma of hospitalization could improve patient satisfaction and outcomes. Efforts such as personalization, providing rest and nourishment, reducing stress disruption and surprises as well as providing a post discharge safety net are strategies to reduce the trauma of hospitalization, improve satisfaction and patient outcomes.
5. Is there anything we can do to make hand-offs safer? The I-PASS hand-off bundle for a systematic hand-off process was reviewed (Illness severity, Patient summary, Action list, Situation awareness, Synthesis by receiver) as a means of reducing medical errors. When used in conjunction with training, faculty development and a culture-change campaign, this was associated with improving patient safety without negatively affecting workflow.
6. How can hospitalists deflate medical bills? Patient expectations of the benefits and harms of clinical interventions influences physician decision making and contributes to overuse and increased healthcare costs. Harm of excessive testing was underestimated in such situations. Conversations with patients, colleagues and the public are crucial to decreasing low value care. Physicians should discuss potential benefits and risks to address patient expectations. In addition, they should seek opportunities to better understand healthcare costs.
7. How big of a problem is antibiotic overuse in hospitals and can we do better? In a national database review, more than half of all patients (55.7%) discharged from a hospital received antibiotics during their stay. There is a wide variation in antibiotic use across hospital wards. Reducing this exposure to broad spectrum antibiotics would lead to a 26% reduction in C. diff infections and reduce antibiotic resistance. To improve this over-utilization, stewardship programs should actively engage and educate clinicians, encourage clear antibiotic documentation in daily progress notes and use 72-hour antibiotic time-out during multidisciplinary rounds. TH

In this session, Drs. Michelle Mourad and Christopher Moriates took a systematic approach to answer quality questions that we commonly encounter in our hospitalist practice. They reviewed current evidence including meta-analyses and systematic reviews to arrive at an answer for various quality-related questions. These are summarized below:

1. What are the common features of interventions that have successfully reduced re-admissions? Effective interventions that enhance patient capacity to reliably access and engage in post-discharge care has been associated with success in decreasing re-admissions.

2. 

   Does patient engagement correlate with decreased resource use or readmissions? Patient activation is defined as knowledge, skills, confidence and inclination to assume responsibility for managing one’s own health. A higher patient activation score reduced the risk of 30-day hospital re-utilization.
3. Does patients’ report of their healthcare experience reflect quality of care? Patient satisfaction scores may be a reflection of their desires (for example, to get pain medications) regardless of clinical benefit. In these situations, quality should be based on achieving a mutual understanding of patient situation and treatment plan between the provider and patient.
4. Is there any relationship between quality of care and health outcomes? Positive associations were found between patient experience and safety/effectiveness. Including patient experience in quality improvement, therefore, may lead to improvements in safety and effectiveness. Reducing the trauma of hospitalization could improve patient satisfaction and outcomes. Efforts such as personalization, providing rest and nourishment, reducing stress disruption and surprises as well as providing a post discharge safety net are strategies to reduce the trauma of hospitalization, improve satisfaction and patient outcomes.
5. Is there anything we can do to make hand-offs safer? The I-PASS hand-off bundle for a systematic hand-off process was reviewed (Illness severity, Patient summary, Action list, Situation awareness, Synthesis by receiver) as a means of reducing medical errors. When used in conjunction with training, faculty development and a culture-change campaign, this was associated with improving patient safety without negatively affecting workflow.
6. How can hospitalists deflate medical bills? Patient expectations of the benefits and harms of clinical interventions influences physician decision making and contributes to overuse and increased healthcare costs. Harm of excessive testing was underestimated in such situations. Conversations with patients, colleagues and the public are crucial to decreasing low value care. Physicians should discuss potential benefits and risks to address patient expectations. In addition, they should seek opportunities to better understand healthcare costs.
7. How big of a problem is antibiotic overuse in hospitals and can we do better? In a national database review, more than half of all patients (55.7%) discharged from a hospital received antibiotics during their stay. There is a wide variation in antibiotic use across hospital wards. Reducing this exposure to broad spectrum antibiotics would lead to a 26% reduction in C. diff infections and reduce antibiotic resistance. To improve this over-utilization, stewardship programs should actively engage and educate clinicians, encourage clear antibiotic documentation in daily progress notes and use 72-hour antibiotic time-out during multidisciplinary rounds. TH

In this session, Drs. Michelle Mourad and Christopher Moriates took a systematic approach to answer quality questions that we commonly encounter in our hospitalist practice. They reviewed current evidence including meta-analyses and systematic reviews to arrive at an answer for various quality-related questions. These are summarized below:

1. What are the common features of interventions that have successfully reduced re-admissions? Effective interventions that enhance patient capacity to reliably access and engage in post-discharge care has been associated with success in decreasing re-admissions.

2. 

   Does patient engagement correlate with decreased resource use or readmissions? Patient activation is defined as knowledge, skills, confidence and inclination to assume responsibility for managing one’s own health. A higher patient activation score reduced the risk of 30-day hospital re-utilization.
3. Does patients’ report of their healthcare experience reflect quality of care? Patient satisfaction scores may be a reflection of their desires (for example, to get pain medications) regardless of clinical benefit. In these situations, quality should be based on achieving a mutual understanding of patient situation and treatment plan between the provider and patient.
4. Is there any relationship between quality of care and health outcomes? Positive associations were found between patient experience and safety/effectiveness. Including patient experience in quality improvement, therefore, may lead to improvements in safety and effectiveness. Reducing the trauma of hospitalization could improve patient satisfaction and outcomes. Efforts such as personalization, providing rest and nourishment, reducing stress disruption and surprises as well as providing a post discharge safety net are strategies to reduce the trauma of hospitalization, improve satisfaction and patient outcomes.
5. Is there anything we can do to make hand-offs safer? The I-PASS hand-off bundle for a systematic hand-off process was reviewed (Illness severity, Patient summary, Action list, Situation awareness, Synthesis by receiver) as a means of reducing medical errors. When used in conjunction with training, faculty development and a culture-change campaign, this was associated with improving patient safety without negatively affecting workflow.
6. How can hospitalists deflate medical bills? Patient expectations of the benefits and harms of clinical interventions influences physician decision making and contributes to overuse and increased healthcare costs. Harm of excessive testing was underestimated in such situations. Conversations with patients, colleagues and the public are crucial to decreasing low value care. Physicians should discuss potential benefits and risks to address patient expectations. In addition, they should seek opportunities to better understand healthcare costs.
7. How big of a problem is antibiotic overuse in hospitals and can we do better? In a national database review, more than half of all patients (55.7%) discharged from a hospital received antibiotics during their stay. There is a wide variation in antibiotic use across hospital wards. Reducing this exposure to broad spectrum antibiotics would lead to a 26% reduction in C. diff infections and reduce antibiotic resistance. To improve this over-utilization, stewardship programs should actively engage and educate clinicians, encourage clear antibiotic documentation in daily progress notes and use 72-hour antibiotic time-out during multidisciplinary rounds. TH

Osteoarthritis (OA) of the first carpometacarpal (CMC) joint is a common disabling condition that mostly affects women over 45 years of age.¹ Surgical intervention is usually indicated in advanced stage OA of the first CMC joint that has failed conservative treatment. Several surgical techniques have been described, including partial or total trapeziectomy, interposition arthroplasty with or without ligament reconstruction,^2,3 metacarpal osteotomy,⁴ hematoma and distraction arthroplasty,⁵ total joint arthroplasty, arthrodesis, and suspensionplasty.⁶ However, no single surgical procedure has proved to be superior.⁷

The Artelon implant (Artelon, Nashville, Tennessee) is a T-shaped spacer composed of a biocompatible and biodegradable polycaprolactone-based polyurethane urea polymer. The developers of the implant first presented its use in CMC OA in 2005.⁸ The device, an endoprosthetic replacement for the CMC joint, was designed to work through 2 modes of action: stabilization of the CMC joint by augmentation of the joint capsule and by formation of a new articular surface at the trapeziometacarpal interface. The interposed biomaterial has been described as preventing bony impingement and allowing time for replacement with a newly formed articular surface as it undergoes slow and controlled degradation.⁸

We present a patient with recurrent CMC pain and disability 4 years after arthroscopic hemitrapeziectomy and Artelon interposition and discuss the associated histologic findings. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 53-year-old man presented with painful disability of right thumb of several months’ duration. Clinical and radiographic evaluation supported the diagnosis of right thumb CMC joint Eaton stage III arthritis (Figures 1A, 1B). Surgical intervention was indicated after a failed course of conservative treatment, including splinting, nonsteroidal anti-inflammatory medications, activity modification, and corticosteroid injection. Preoperatively, the patient reported a visual analog scale (VAS) score of 8 with activity and 5 at rest, and a Disabilities of the Arm, Shoulder, and Hand (DASH) score of 72.5.

Arthroscopic débridement, hemitrapeziectomy, and interposition arthroplasty with the Artelon spacer were performed. Using standard thumb arthroscopy, 3 mm of the distal trapezium was excised and shaped parallel to scaphotrapezial joint. The wings of the standard-sized Artelon spacer were removed, and the central (articulating) portion was rolled into a tube and inserted through the 1R portal (directly radial to the abductor pollicis longus tendon) into the trapezial space. The Artelon spacer was unrolled within the joint to cover the remaining trapezium and was stabilized with the placement of a 0.045-inch Kirschner wire through the metacarpal, the spacer, and the remaining trapezium. The patient used a thumb spica splint for 4 weeks.

The postoperative radiographs showed a smooth and adequate hemitrapeziectomy with good alignment and implant position (Figures 2A, 2B). Four weeks after surgery, the Kirschner wire and cast were removed and physical therapy was initiated. The patient’s CMC pain gradually subsided. At the 3-month postoperative visit, the patient’s VAS score was 3 with activity and 1 at rest, with a DASH score of 28. His key pinch strength was 12 lb, compared with 20 lb on the contralateral side. At 6 months, the patient’s VAS score was 1 with activity and 0 at rest, with a DASH score of 12. His key pinch strength was 18 lb, compared with 22 lb on the contralateral side. At his 2-year postoperative visit, the patient was doing well with the exception of some mild residual pain when he opened tight jars. His VAS score was 1 with activity and 0 at rest, with a DASH score of 3. His key pinch strength was 20 lb, compared with 23 lb on the contralateral side. Radiographs showed good maintenance of the CMC space.

Four years postoperatively, the patient presented with worsening right CMC pain with decrease in pinch strength that interfered with his activities of daily living. His VAS score was 9 with activity and 6 at rest, with a DASH score of 70. On examination, pinch strength was 16 lb, compared with 22 lb on the contralateral side. Radiographs showed advancing arthritis with new osteophyte formation and irregular contour of distal trapezium (Figures 3A, 3B). The symptoms were refractory to conservative measures and continued to interfere with his activities of daily living. Revision surgical intervention was indicated and pursued in the form of an open CMC arthroplasty.

The intraoperative findings revealed degradation and disorganization of the Artelon implant within the central portion of the remaining distal trapezium. Rim osteophytes, especially along the ulnar aspect, were noted. Total trapeziectomy and débridement within the CMC space and suture-button suspensionplasty were performed.⁸ Slight degenerative changes of the distal scaphoid were also noted. The incision was irrigated, closed, and stabilized in a thumb spica splint (Figures 4A, 4B).

The harvested trapezium was immediately immersed in buffered formalin. The bone tissue was decalcified, dehydrated, embedded in paraffin, and sectioned in the coronal plane. The sections were stained with safranin O and trichrome, and light microscopic analysis was performed. Central erosion of distal trapezium without smooth resurfacing soft-tissue formation was noted grossly (Figure 5A) and microscopically (Figures 5B, 5C). The histologic morphology of the soft tissue over the distal trapezium was significantly different when compared with the smooth hyaline cartilage at the preserved trapezio-trapezoidal joint (Figures 6A-6F). Microscopic analysis also showed multinucleated giant cells within the soft tissue surrounding the degraded Artelon B (Figure 7).

Immunohistochemical analysis was performed to identify type I and type II collagen using the Histostain-Plus,3rd Gen IHC Detection Kit (Invitrogen Corporation, Camarillo, California) (Figures 8A-8F).⁹ The immunohistochemical stain was used to identify new hyaline cartilage formation that may have been induced by the Artelon as the resurfacing articulation. Hyaline cartilage contains mainly type II collagen, and collagen types VI, IX, X, XI, XII, and XIV all contribute to the mature matrix.¹⁰ Little type I collagen is found in hyaline cartilage. The results showed that the soft tissue over the distal trapezium with embedded Artelon fiber contained both type I and type II collagen. There was no visible hyaline cartilage formation induced by the Artelon. Both morphologic analysis and immunohistochemical staining revealed that the soft-tissue growth into the Artelon spacer on the distal trapezium consisted primarily of fibrocartilaginous tissue, which is composed mainly of type I collagen with some type II collagen.

Two weeks after total surgical excision of the Artelon implant, total trapeziectomy and suture-button suspensionplasty, the sutures were removed and physical therapy was initiated. Radiographs showed good alignment and position of thumb metacarpal with good maintenance of the implant and CMC space. Four months postoperatively, the patient reported that he was doing well without pain and without interference in his activities of daily living. On examination, the patient exhibited no pain with the CMC grind maneuver. Radial abduction of the right thumb was 85° and palmar abduction was 90° (compared with 100° and 90° of the left thumb), obtained by measuring the angle between thumb and index finger, respectively. Opposition was to the small finger metacarpophalangeal joint. Grip strength was 72 lb and pinch strength was 20 lb (compared with 70 lb and 24 lb, respectively, on the contralateral side). 

Discussion

The use of Artelon as an endoprosthetic spacer to treat osteoarthritis in the CMC joint of the thumb appears to stabilize and resurface the joint while avoiding total trapeziectomy.⁸ Nilsson and colleagues⁸ presented a prospective study concluding that the Artelon CMC spacer provided better pinch strength when compared with a traditional abductor pollicis longus suspensionplasty procedure. This study also suggested incorporation of the device in the surface of the adjacent bone with no signs of foreign-body reaction. The synthetic material was shown to be safe and biocompatible in vitro and in animal studies.^11-13

This case report describes the gross and histologic findings after continued pain led to explantation 4 years after arthroscopic partial trapeziectomy and insertion of the spacer. Intraoperative findings at this stage showed lack of incorporation of the Artelon material, central destruction of distal trapezium, and no evidence of smooth articular surface formation. Our histologic analysis showed only poorly organized fibrocartilage within the CMC space rather than a smooth articular surface. These histologic findings may correlate more with Jörheim and colleagues’¹⁴ matched cohort study, which showed that short-term outcomes after treatment with the Artelon implant were not clinically superior to those of tendon suspension-interposition arthroplasties. Multinucleated giant cells were also seen in our specimens. Choung and Tan¹⁵ presented a case report of foreign-body reaction to the Artelon spacer with histologic findings. The foreign body–type reactions associated with Artelon resulted in multinucleated giant cells in their specimens. Recently, several case reports have described similar foreign-body reactions.¹⁶ Nilsson and coauthors¹⁷ presented a randomized, controlled, multicenter study of 109 patients. They reported the Artelon CMC spacer did not result in superior results compared with tendon interposition arthroplasty. In a study by Gretzer and colleagues,¹⁸ the authors suggested that chronic inflammation may result from unstable Artelon fixation instead of the foreign-body reaction.

It is possible that the central erosion of the distal trapezium seen in our case may have resulted from chronic inflammation caused by foreign-body reaction and/or an unstably fixed spacer. The spacer was transfixed to the remaining trapezium in the CMC joint with a Kirschner wire followed by immobilization for 4 weeks. Poor soft-tissue integration of the Artelon spacer may have led to unintended motion and chronic inflammation, which may have also resulted in erosion between the Artelon spacer and the trapezium, leading to central destruction of the distal trapezium. Lastly, the byproducts formed by the degradation of the spacer may have resulted in erosion of the remaining trapezium.

Conclusion

The Artelon CMC spacer used in this patient provided comparable, but not superior, clinical results to other procedures. Histologically, the new articular surface in our patient was formed with rugged fibrocartilage instead of the expected smooth cartilaginous surface. The chronic inflammatory reaction may have resulted from foreign-body reaction, unstable implant fixation, or poor soft-tissue integration. This inflammatory reaction may have contributed to the patient’s recurrence of symptoms. These findings support recent clinical data that suggest the use of the Artelon spacer may not provide superior results to other surgical options for the treatment of CMC joint arthritis.

Osteoarthritis (OA) of the first carpometacarpal (CMC) joint is a common disabling condition that mostly affects women over 45 years of age.¹ Surgical intervention is usually indicated in advanced stage OA of the first CMC joint that has failed conservative treatment. Several surgical techniques have been described, including partial or total trapeziectomy, interposition arthroplasty with or without ligament reconstruction,^2,3 metacarpal osteotomy,⁴ hematoma and distraction arthroplasty,⁵ total joint arthroplasty, arthrodesis, and suspensionplasty.⁶ However, no single surgical procedure has proved to be superior.⁷

The Artelon implant (Artelon, Nashville, Tennessee) is a T-shaped spacer composed of a biocompatible and biodegradable polycaprolactone-based polyurethane urea polymer. The developers of the implant first presented its use in CMC OA in 2005.⁸ The device, an endoprosthetic replacement for the CMC joint, was designed to work through 2 modes of action: stabilization of the CMC joint by augmentation of the joint capsule and by formation of a new articular surface at the trapeziometacarpal interface. The interposed biomaterial has been described as preventing bony impingement and allowing time for replacement with a newly formed articular surface as it undergoes slow and controlled degradation.⁸

We present a patient with recurrent CMC pain and disability 4 years after arthroscopic hemitrapeziectomy and Artelon interposition and discuss the associated histologic findings. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 53-year-old man presented with painful disability of right thumb of several months’ duration. Clinical and radiographic evaluation supported the diagnosis of right thumb CMC joint Eaton stage III arthritis (Figures 1A, 1B). Surgical intervention was indicated after a failed course of conservative treatment, including splinting, nonsteroidal anti-inflammatory medications, activity modification, and corticosteroid injection. Preoperatively, the patient reported a visual analog scale (VAS) score of 8 with activity and 5 at rest, and a Disabilities of the Arm, Shoulder, and Hand (DASH) score of 72.5.

Arthroscopic débridement, hemitrapeziectomy, and interposition arthroplasty with the Artelon spacer were performed. Using standard thumb arthroscopy, 3 mm of the distal trapezium was excised and shaped parallel to scaphotrapezial joint. The wings of the standard-sized Artelon spacer were removed, and the central (articulating) portion was rolled into a tube and inserted through the 1R portal (directly radial to the abductor pollicis longus tendon) into the trapezial space. The Artelon spacer was unrolled within the joint to cover the remaining trapezium and was stabilized with the placement of a 0.045-inch Kirschner wire through the metacarpal, the spacer, and the remaining trapezium. The patient used a thumb spica splint for 4 weeks.

The postoperative radiographs showed a smooth and adequate hemitrapeziectomy with good alignment and implant position (Figures 2A, 2B). Four weeks after surgery, the Kirschner wire and cast were removed and physical therapy was initiated. The patient’s CMC pain gradually subsided. At the 3-month postoperative visit, the patient’s VAS score was 3 with activity and 1 at rest, with a DASH score of 28. His key pinch strength was 12 lb, compared with 20 lb on the contralateral side. At 6 months, the patient’s VAS score was 1 with activity and 0 at rest, with a DASH score of 12. His key pinch strength was 18 lb, compared with 22 lb on the contralateral side. At his 2-year postoperative visit, the patient was doing well with the exception of some mild residual pain when he opened tight jars. His VAS score was 1 with activity and 0 at rest, with a DASH score of 3. His key pinch strength was 20 lb, compared with 23 lb on the contralateral side. Radiographs showed good maintenance of the CMC space.

Four years postoperatively, the patient presented with worsening right CMC pain with decrease in pinch strength that interfered with his activities of daily living. His VAS score was 9 with activity and 6 at rest, with a DASH score of 70. On examination, pinch strength was 16 lb, compared with 22 lb on the contralateral side. Radiographs showed advancing arthritis with new osteophyte formation and irregular contour of distal trapezium (Figures 3A, 3B). The symptoms were refractory to conservative measures and continued to interfere with his activities of daily living. Revision surgical intervention was indicated and pursued in the form of an open CMC arthroplasty.

The intraoperative findings revealed degradation and disorganization of the Artelon implant within the central portion of the remaining distal trapezium. Rim osteophytes, especially along the ulnar aspect, were noted. Total trapeziectomy and débridement within the CMC space and suture-button suspensionplasty were performed.⁸ Slight degenerative changes of the distal scaphoid were also noted. The incision was irrigated, closed, and stabilized in a thumb spica splint (Figures 4A, 4B).

The harvested trapezium was immediately immersed in buffered formalin. The bone tissue was decalcified, dehydrated, embedded in paraffin, and sectioned in the coronal plane. The sections were stained with safranin O and trichrome, and light microscopic analysis was performed. Central erosion of distal trapezium without smooth resurfacing soft-tissue formation was noted grossly (Figure 5A) and microscopically (Figures 5B, 5C). The histologic morphology of the soft tissue over the distal trapezium was significantly different when compared with the smooth hyaline cartilage at the preserved trapezio-trapezoidal joint (Figures 6A-6F). Microscopic analysis also showed multinucleated giant cells within the soft tissue surrounding the degraded Artelon B (Figure 7).

Immunohistochemical analysis was performed to identify type I and type II collagen using the Histostain-Plus,3rd Gen IHC Detection Kit (Invitrogen Corporation, Camarillo, California) (Figures 8A-8F).⁹ The immunohistochemical stain was used to identify new hyaline cartilage formation that may have been induced by the Artelon as the resurfacing articulation. Hyaline cartilage contains mainly type II collagen, and collagen types VI, IX, X, XI, XII, and XIV all contribute to the mature matrix.¹⁰ Little type I collagen is found in hyaline cartilage. The results showed that the soft tissue over the distal trapezium with embedded Artelon fiber contained both type I and type II collagen. There was no visible hyaline cartilage formation induced by the Artelon. Both morphologic analysis and immunohistochemical staining revealed that the soft-tissue growth into the Artelon spacer on the distal trapezium consisted primarily of fibrocartilaginous tissue, which is composed mainly of type I collagen with some type II collagen.

Two weeks after total surgical excision of the Artelon implant, total trapeziectomy and suture-button suspensionplasty, the sutures were removed and physical therapy was initiated. Radiographs showed good alignment and position of thumb metacarpal with good maintenance of the implant and CMC space. Four months postoperatively, the patient reported that he was doing well without pain and without interference in his activities of daily living. On examination, the patient exhibited no pain with the CMC grind maneuver. Radial abduction of the right thumb was 85° and palmar abduction was 90° (compared with 100° and 90° of the left thumb), obtained by measuring the angle between thumb and index finger, respectively. Opposition was to the small finger metacarpophalangeal joint. Grip strength was 72 lb and pinch strength was 20 lb (compared with 70 lb and 24 lb, respectively, on the contralateral side). 

Discussion

The use of Artelon as an endoprosthetic spacer to treat osteoarthritis in the CMC joint of the thumb appears to stabilize and resurface the joint while avoiding total trapeziectomy.⁸ Nilsson and colleagues⁸ presented a prospective study concluding that the Artelon CMC spacer provided better pinch strength when compared with a traditional abductor pollicis longus suspensionplasty procedure. This study also suggested incorporation of the device in the surface of the adjacent bone with no signs of foreign-body reaction. The synthetic material was shown to be safe and biocompatible in vitro and in animal studies.^11-13

This case report describes the gross and histologic findings after continued pain led to explantation 4 years after arthroscopic partial trapeziectomy and insertion of the spacer. Intraoperative findings at this stage showed lack of incorporation of the Artelon material, central destruction of distal trapezium, and no evidence of smooth articular surface formation. Our histologic analysis showed only poorly organized fibrocartilage within the CMC space rather than a smooth articular surface. These histologic findings may correlate more with Jörheim and colleagues’¹⁴ matched cohort study, which showed that short-term outcomes after treatment with the Artelon implant were not clinically superior to those of tendon suspension-interposition arthroplasties. Multinucleated giant cells were also seen in our specimens. Choung and Tan¹⁵ presented a case report of foreign-body reaction to the Artelon spacer with histologic findings. The foreign body–type reactions associated with Artelon resulted in multinucleated giant cells in their specimens. Recently, several case reports have described similar foreign-body reactions.¹⁶ Nilsson and coauthors¹⁷ presented a randomized, controlled, multicenter study of 109 patients. They reported the Artelon CMC spacer did not result in superior results compared with tendon interposition arthroplasty. In a study by Gretzer and colleagues,¹⁸ the authors suggested that chronic inflammation may result from unstable Artelon fixation instead of the foreign-body reaction.

It is possible that the central erosion of the distal trapezium seen in our case may have resulted from chronic inflammation caused by foreign-body reaction and/or an unstably fixed spacer. The spacer was transfixed to the remaining trapezium in the CMC joint with a Kirschner wire followed by immobilization for 4 weeks. Poor soft-tissue integration of the Artelon spacer may have led to unintended motion and chronic inflammation, which may have also resulted in erosion between the Artelon spacer and the trapezium, leading to central destruction of the distal trapezium. Lastly, the byproducts formed by the degradation of the spacer may have resulted in erosion of the remaining trapezium.

Conclusion

The Artelon CMC spacer used in this patient provided comparable, but not superior, clinical results to other procedures. Histologically, the new articular surface in our patient was formed with rugged fibrocartilage instead of the expected smooth cartilaginous surface. The chronic inflammatory reaction may have resulted from foreign-body reaction, unstable implant fixation, or poor soft-tissue integration. This inflammatory reaction may have contributed to the patient’s recurrence of symptoms. These findings support recent clinical data that suggest the use of the Artelon spacer may not provide superior results to other surgical options for the treatment of CMC joint arthritis.

Osteoarthritis (OA) of the first carpometacarpal (CMC) joint is a common disabling condition that mostly affects women over 45 years of age.¹ Surgical intervention is usually indicated in advanced stage OA of the first CMC joint that has failed conservative treatment. Several surgical techniques have been described, including partial or total trapeziectomy, interposition arthroplasty with or without ligament reconstruction,^2,3 metacarpal osteotomy,⁴ hematoma and distraction arthroplasty,⁵ total joint arthroplasty, arthrodesis, and suspensionplasty.⁶ However, no single surgical procedure has proved to be superior.⁷

The Artelon implant (Artelon, Nashville, Tennessee) is a T-shaped spacer composed of a biocompatible and biodegradable polycaprolactone-based polyurethane urea polymer. The developers of the implant first presented its use in CMC OA in 2005.⁸ The device, an endoprosthetic replacement for the CMC joint, was designed to work through 2 modes of action: stabilization of the CMC joint by augmentation of the joint capsule and by formation of a new articular surface at the trapeziometacarpal interface. The interposed biomaterial has been described as preventing bony impingement and allowing time for replacement with a newly formed articular surface as it undergoes slow and controlled degradation.⁸

We present a patient with recurrent CMC pain and disability 4 years after arthroscopic hemitrapeziectomy and Artelon interposition and discuss the associated histologic findings. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 53-year-old man presented with painful disability of right thumb of several months’ duration. Clinical and radiographic evaluation supported the diagnosis of right thumb CMC joint Eaton stage III arthritis (Figures 1A, 1B). Surgical intervention was indicated after a failed course of conservative treatment, including splinting, nonsteroidal anti-inflammatory medications, activity modification, and corticosteroid injection. Preoperatively, the patient reported a visual analog scale (VAS) score of 8 with activity and 5 at rest, and a Disabilities of the Arm, Shoulder, and Hand (DASH) score of 72.5.

Arthroscopic débridement, hemitrapeziectomy, and interposition arthroplasty with the Artelon spacer were performed. Using standard thumb arthroscopy, 3 mm of the distal trapezium was excised and shaped parallel to scaphotrapezial joint. The wings of the standard-sized Artelon spacer were removed, and the central (articulating) portion was rolled into a tube and inserted through the 1R portal (directly radial to the abductor pollicis longus tendon) into the trapezial space. The Artelon spacer was unrolled within the joint to cover the remaining trapezium and was stabilized with the placement of a 0.045-inch Kirschner wire through the metacarpal, the spacer, and the remaining trapezium. The patient used a thumb spica splint for 4 weeks.

The postoperative radiographs showed a smooth and adequate hemitrapeziectomy with good alignment and implant position (Figures 2A, 2B). Four weeks after surgery, the Kirschner wire and cast were removed and physical therapy was initiated. The patient’s CMC pain gradually subsided. At the 3-month postoperative visit, the patient’s VAS score was 3 with activity and 1 at rest, with a DASH score of 28. His key pinch strength was 12 lb, compared with 20 lb on the contralateral side. At 6 months, the patient’s VAS score was 1 with activity and 0 at rest, with a DASH score of 12. His key pinch strength was 18 lb, compared with 22 lb on the contralateral side. At his 2-year postoperative visit, the patient was doing well with the exception of some mild residual pain when he opened tight jars. His VAS score was 1 with activity and 0 at rest, with a DASH score of 3. His key pinch strength was 20 lb, compared with 23 lb on the contralateral side. Radiographs showed good maintenance of the CMC space.

Four years postoperatively, the patient presented with worsening right CMC pain with decrease in pinch strength that interfered with his activities of daily living. His VAS score was 9 with activity and 6 at rest, with a DASH score of 70. On examination, pinch strength was 16 lb, compared with 22 lb on the contralateral side. Radiographs showed advancing arthritis with new osteophyte formation and irregular contour of distal trapezium (Figures 3A, 3B). The symptoms were refractory to conservative measures and continued to interfere with his activities of daily living. Revision surgical intervention was indicated and pursued in the form of an open CMC arthroplasty.

The intraoperative findings revealed degradation and disorganization of the Artelon implant within the central portion of the remaining distal trapezium. Rim osteophytes, especially along the ulnar aspect, were noted. Total trapeziectomy and débridement within the CMC space and suture-button suspensionplasty were performed.⁸ Slight degenerative changes of the distal scaphoid were also noted. The incision was irrigated, closed, and stabilized in a thumb spica splint (Figures 4A, 4B).

The harvested trapezium was immediately immersed in buffered formalin. The bone tissue was decalcified, dehydrated, embedded in paraffin, and sectioned in the coronal plane. The sections were stained with safranin O and trichrome, and light microscopic analysis was performed. Central erosion of distal trapezium without smooth resurfacing soft-tissue formation was noted grossly (Figure 5A) and microscopically (Figures 5B, 5C). The histologic morphology of the soft tissue over the distal trapezium was significantly different when compared with the smooth hyaline cartilage at the preserved trapezio-trapezoidal joint (Figures 6A-6F). Microscopic analysis also showed multinucleated giant cells within the soft tissue surrounding the degraded Artelon B (Figure 7).

Immunohistochemical analysis was performed to identify type I and type II collagen using the Histostain-Plus,3rd Gen IHC Detection Kit (Invitrogen Corporation, Camarillo, California) (Figures 8A-8F).⁹ The immunohistochemical stain was used to identify new hyaline cartilage formation that may have been induced by the Artelon as the resurfacing articulation. Hyaline cartilage contains mainly type II collagen, and collagen types VI, IX, X, XI, XII, and XIV all contribute to the mature matrix.¹⁰ Little type I collagen is found in hyaline cartilage. The results showed that the soft tissue over the distal trapezium with embedded Artelon fiber contained both type I and type II collagen. There was no visible hyaline cartilage formation induced by the Artelon. Both morphologic analysis and immunohistochemical staining revealed that the soft-tissue growth into the Artelon spacer on the distal trapezium consisted primarily of fibrocartilaginous tissue, which is composed mainly of type I collagen with some type II collagen.

Two weeks after total surgical excision of the Artelon implant, total trapeziectomy and suture-button suspensionplasty, the sutures were removed and physical therapy was initiated. Radiographs showed good alignment and position of thumb metacarpal with good maintenance of the implant and CMC space. Four months postoperatively, the patient reported that he was doing well without pain and without interference in his activities of daily living. On examination, the patient exhibited no pain with the CMC grind maneuver. Radial abduction of the right thumb was 85° and palmar abduction was 90° (compared with 100° and 90° of the left thumb), obtained by measuring the angle between thumb and index finger, respectively. Opposition was to the small finger metacarpophalangeal joint. Grip strength was 72 lb and pinch strength was 20 lb (compared with 70 lb and 24 lb, respectively, on the contralateral side). 

Discussion

The use of Artelon as an endoprosthetic spacer to treat osteoarthritis in the CMC joint of the thumb appears to stabilize and resurface the joint while avoiding total trapeziectomy.⁸ Nilsson and colleagues⁸ presented a prospective study concluding that the Artelon CMC spacer provided better pinch strength when compared with a traditional abductor pollicis longus suspensionplasty procedure. This study also suggested incorporation of the device in the surface of the adjacent bone with no signs of foreign-body reaction. The synthetic material was shown to be safe and biocompatible in vitro and in animal studies.^11-13

This case report describes the gross and histologic findings after continued pain led to explantation 4 years after arthroscopic partial trapeziectomy and insertion of the spacer. Intraoperative findings at this stage showed lack of incorporation of the Artelon material, central destruction of distal trapezium, and no evidence of smooth articular surface formation. Our histologic analysis showed only poorly organized fibrocartilage within the CMC space rather than a smooth articular surface. These histologic findings may correlate more with Jörheim and colleagues’¹⁴ matched cohort study, which showed that short-term outcomes after treatment with the Artelon implant were not clinically superior to those of tendon suspension-interposition arthroplasties. Multinucleated giant cells were also seen in our specimens. Choung and Tan¹⁵ presented a case report of foreign-body reaction to the Artelon spacer with histologic findings. The foreign body–type reactions associated with Artelon resulted in multinucleated giant cells in their specimens. Recently, several case reports have described similar foreign-body reactions.¹⁶ Nilsson and coauthors¹⁷ presented a randomized, controlled, multicenter study of 109 patients. They reported the Artelon CMC spacer did not result in superior results compared with tendon interposition arthroplasty. In a study by Gretzer and colleagues,¹⁸ the authors suggested that chronic inflammation may result from unstable Artelon fixation instead of the foreign-body reaction.

It is possible that the central erosion of the distal trapezium seen in our case may have resulted from chronic inflammation caused by foreign-body reaction and/or an unstably fixed spacer. The spacer was transfixed to the remaining trapezium in the CMC joint with a Kirschner wire followed by immobilization for 4 weeks. Poor soft-tissue integration of the Artelon spacer may have led to unintended motion and chronic inflammation, which may have also resulted in erosion between the Artelon spacer and the trapezium, leading to central destruction of the distal trapezium. Lastly, the byproducts formed by the degradation of the spacer may have resulted in erosion of the remaining trapezium.

Conclusion

The Artelon CMC spacer used in this patient provided comparable, but not superior, clinical results to other procedures. Histologically, the new articular surface in our patient was formed with rugged fibrocartilage instead of the expected smooth cartilaginous surface. The chronic inflammatory reaction may have resulted from foreign-body reaction, unstable implant fixation, or poor soft-tissue integration. This inflammatory reaction may have contributed to the patient’s recurrence of symptoms. These findings support recent clinical data that suggest the use of the Artelon spacer may not provide superior results to other surgical options for the treatment of CMC joint arthritis.

Symptomatic synovial cyst formation is a rare, late occurrence after total knee arthroplasty (TKA); these cysts are generally discovered by chance. If they enlarge, they can result in significant pain and disability. A few case reports have described the development of very large cysts that required revision knee surgery. In this patient, polyethylene wear disease after TKA resulted in a massive synovial cyst that extended into the posterior compartment of the leg, as well as a progressive peripheral neuropathy. Revision of a loose patella component and worn polyethylene liner with complete synovectomy, plus decompression of the cyst via needle aspiration, resulted in an excellent short-term outcome.

To the author’s knowledge, this is the first case report of peripheral neuropathy of the tibial nerve secondary to a massive Baker cyst after total knee replacement. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

The patient was a 65-year-old woman with a complex medical history and multiple left knee surgeries, including a high tibial osteotomy and subsequent cemented TKA performed in the mid-1990s. She presented to the orthopedic department at a university hospital with complaints of knee pain 13 years after TKA. Observation was recommended; however, she was lost to follow-up.

The patient presented to her primary care physician (PCP) 16 years after TKA with a very large, painful mass in the back of her left leg. An ultrasound showed a large Baker cyst, and the patient was sent to interventional radiology. A few months later, she had an ultrasound-guided aspiration into the left calf, which produced 300 mL of thick synovial fluid. A cell count was not performed, but bacterial cultures were negative. Immediately after the aspiration, the pain was relieved.

Approximately 3 months after the aspiration, she presented again to her PCP with re-accumulation of fluid in the back of her left leg and severe leg pain. She was referred to a different orthopedic surgeon who determined that the risk of surgery was too great given her complex medical history.

The woman’s PCP referred the woman to our office 6 months after the aspiration. On presentation, her pain was localized to the posterior left leg. She reported the pain level as a constant 9 out of 10 on the visual analog scale, despite ingesting high doses of narcotics, including oxycontin and morphine. Her physical examination was remarkable for an ill-defined large calf mass. The posterior compartment of her left leg was firm and severely tender, similar to the characteristic findings seen in acute compartment syndrome.

Radiographs showed evidence of asymmetric polyethylene wear on the medial side of the knee (Figures 1A, 1B). Serum labs were ordered to evaluate for infection. C-reactive protein was mildly elevated at 5.5 mg/L (normal range, 0-5 mg/L); however, the erythrocyte sedimentation rate was normal at 12 mm/h (normal range, 0-20 mm/h). Magnetic resonance imaging of the left lower extremity with intravenous contrast showed the presence of a very large Baker cyst contained within the posterior compartment of the knee and a smaller surrounding cyst adjacent to the popliteal neurovascular bundle (Figure 2).

The Baker cyst was re-aspirated in the office. The automated synovial fluid cell count could not be performed because of high fluid viscosity. However, a manual review of the fluid specimen under light microscopy revealed proteinaceous, viscous tan-colored fluid containing no neutrophils and a few macrophages. Fluid cytology was also sent for review under polarizing light microscopy as described by Peterson and colleagues.¹ Scattered fragments of polarizable foreign material were consistent with polyethylene debris (Figure 3). 

The patient was counseled about the risks and benefits of surgery and was offered revision TKA with polyethylene liner exchange and synovectomy, only after complete cessation of smoking. She underwent serum nicotine monitoring to ensure tobacco cessation; however, she also reported the onset of a progressive sensory deficit over her left foot during this period. Although her medical history was remarkable for spinal stenosis, she noted a progressive decline in sensory function and new-onset paresthesia of her left foot.

An urgent consult to neurology was requested for nerve conduction studies. According to the electrodiagnostic study, the patient had a moderately severe left tibial neuropathy, likely at the popliteal fossa or distal to it. The nerve conduction study showed a chronic tibial nerve peripheral compressive mononeuropathy, and she was immediately scheduled for revision knee surgery with decompression of her Baker cyst to prevent further neurologic deficit.

During surgery, the knee joint exhibited hypertrophic synovitis with a characteristic pale-yellowish discoloration secondary to significant polyethylene wear disease (Figure 4). The polyethylene liner was severely worn with pitting, cracking, and delamination (Figure 5). While the patellar component was grossly loose, the tibial and femoral components were stable. After a complete synovectomy, the loose patellar component and tibial polyethylene liner were replaced. Osteolytic areas within the tibia underwent curettage and allograft impaction grafting. Lastly, decompression of the ruptured Baker cyst was performed via a 16-gauge needle placed in the posterior compartment of the left leg. The calf was gently squeezed with a “milking” maneuver, which yielded approximately 200 mL of thick, mucoid yellowish-brown synovial fluid resembling tapioca pudding (Figure 6).

Postoperatively, all intraoperative cultures were negative, and the patient was followed closely at 1 week, 2 weeks, 6 weeks, and 3 months after the surgery. At her latest follow-up, the posterior leg compartment remained decompressed and her progressive sensory deficit had nearly resolved. Moreover, the left leg and posterior knee pain completely resolved.

Discussion

A leading cause of TKA failure is attributed to aseptic loosening from polyethylene wear disease.² Implanted high-molecular-weight polyethylene (HMWPE) liners are known to undergo a variety of mechanical wear patterns within the knee. Observed patterns include pitting, scratching, burnishing, scratching, and delamination, which can all liberate numerous fine polyethylene particles.³ This wear debris induces macrophage phagocytosis that triggers an inflammatory reaction within the knee joint and can lead to synovitis, repeat effusions and, ultimately, to aseptic loosening.

Prior to 1996, polyethylene used in total knee replacement underwent a sterilization process in air. This oxygen-rich environment led to the development of free radical formation within the HMWPE. Ultimately, this had a detrimental effect on the polyethylene, leading to the formation of increased wear debris.⁴

Subsequently, orthopedic companies have changed their sterilization and manufacturing methods. Polyethylene components now undergo a variety of processes to eliminate or reduce oxidation, free-radical formation, and mechanical wear debris. Now, sterilization typically takes place in an inert atmospheric environment. Modern HMWPE implants often undergo higher irradiation to induce mechanical cross-linking, followed by either a re-annealing or remelting step. In other cases, manufacturers “dope” their polyethylene with vitamin E to quench free radicals within the material. While these steps have reduced the number of in vitro wear particles, the problem of wear debris, subsequent osteolysis, and aseptic loosening has not been eliminated.^1-5 

Polyethylene wear debris within the synovial fluid or tissue of failed TKAs can be identified with scanning electron microscopy or by light microscopy utilizing polarized light.¹ In this particular case, wear debris was confirmed within the synovial tissue and in the fluid of the Baker cyst by microscopic analysis.

Formation of a popliteal or Baker cyst as a result of polyethylene wear disease is an infrequent but known complication of TKA. Reports have demonstrated variable success in cyst eradication when revision surgery is performed on knees with synovial cysts. Most of these reports indicate that cyst formation tends to occur as a late complication (7 or more years) after TKA.^6-12

Treatment options may include skillful observation with close follow-up or revision surgery. Polyethylene exchange with synovectomy when feasible, as well as component revision with or without excision of the synovial cyst, are surgical options.

Niki and colleagues¹³ described a gigantic popliteal synovial cyst caused by wear particles after TKA. In this report, the surgeon performed a synovectomy and polyethylene liner exchange with retention of prosthetic components. At 12-month follow-up, the patient was reported to be doing well.

Mavrogenis and coauthors¹⁴ reported a wear debris–induced pseudotumor in the popliteal fossa and calf after TKA. In this case, in addition to the synovectomy, the surgeon removed all prosthetic components and used a semi-constrained implant to revise the knee. At 30-month follow-up, the patient reported having a painless knee.

While case reports have indicated that revision TKA for large, painful synovial cysts is a reasonable treatment option in carefully selected patients, there is a paucity of literature on this subject. Moreover, the present case appears to be the first literature report of a tibial nerve compressive neuropathy secondary to a synovial cyst after TKA.

Conclusion

In this report, polyethylene wear disease after TKA resulted in a massive synovial cyst extending into the posterior compartment of the leg. A progressive peripheral neuropathy confirmed by electromyography was also discovered. The patient underwent revision of a loose patellar component and worn polyethylene liner with complete synovectomy plus decompression of the cyst via needle aspiration. This resulted in an excellent short-term outcome with resolution of pain and significant improvement of the peripheral neuropathy 3 months after surgery.

Symptomatic synovial cyst formation is a rare, late occurrence after total knee arthroplasty (TKA); these cysts are generally discovered by chance. If they enlarge, they can result in significant pain and disability. A few case reports have described the development of very large cysts that required revision knee surgery. In this patient, polyethylene wear disease after TKA resulted in a massive synovial cyst that extended into the posterior compartment of the leg, as well as a progressive peripheral neuropathy. Revision of a loose patella component and worn polyethylene liner with complete synovectomy, plus decompression of the cyst via needle aspiration, resulted in an excellent short-term outcome.

To the author’s knowledge, this is the first case report of peripheral neuropathy of the tibial nerve secondary to a massive Baker cyst after total knee replacement. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

The patient was a 65-year-old woman with a complex medical history and multiple left knee surgeries, including a high tibial osteotomy and subsequent cemented TKA performed in the mid-1990s. She presented to the orthopedic department at a university hospital with complaints of knee pain 13 years after TKA. Observation was recommended; however, she was lost to follow-up.

The patient presented to her primary care physician (PCP) 16 years after TKA with a very large, painful mass in the back of her left leg. An ultrasound showed a large Baker cyst, and the patient was sent to interventional radiology. A few months later, she had an ultrasound-guided aspiration into the left calf, which produced 300 mL of thick synovial fluid. A cell count was not performed, but bacterial cultures were negative. Immediately after the aspiration, the pain was relieved.

Approximately 3 months after the aspiration, she presented again to her PCP with re-accumulation of fluid in the back of her left leg and severe leg pain. She was referred to a different orthopedic surgeon who determined that the risk of surgery was too great given her complex medical history.

The woman’s PCP referred the woman to our office 6 months after the aspiration. On presentation, her pain was localized to the posterior left leg. She reported the pain level as a constant 9 out of 10 on the visual analog scale, despite ingesting high doses of narcotics, including oxycontin and morphine. Her physical examination was remarkable for an ill-defined large calf mass. The posterior compartment of her left leg was firm and severely tender, similar to the characteristic findings seen in acute compartment syndrome.

Radiographs showed evidence of asymmetric polyethylene wear on the medial side of the knee (Figures 1A, 1B). Serum labs were ordered to evaluate for infection. C-reactive protein was mildly elevated at 5.5 mg/L (normal range, 0-5 mg/L); however, the erythrocyte sedimentation rate was normal at 12 mm/h (normal range, 0-20 mm/h). Magnetic resonance imaging of the left lower extremity with intravenous contrast showed the presence of a very large Baker cyst contained within the posterior compartment of the knee and a smaller surrounding cyst adjacent to the popliteal neurovascular bundle (Figure 2).

The Baker cyst was re-aspirated in the office. The automated synovial fluid cell count could not be performed because of high fluid viscosity. However, a manual review of the fluid specimen under light microscopy revealed proteinaceous, viscous tan-colored fluid containing no neutrophils and a few macrophages. Fluid cytology was also sent for review under polarizing light microscopy as described by Peterson and colleagues.¹ Scattered fragments of polarizable foreign material were consistent with polyethylene debris (Figure 3). 

The patient was counseled about the risks and benefits of surgery and was offered revision TKA with polyethylene liner exchange and synovectomy, only after complete cessation of smoking. She underwent serum nicotine monitoring to ensure tobacco cessation; however, she also reported the onset of a progressive sensory deficit over her left foot during this period. Although her medical history was remarkable for spinal stenosis, she noted a progressive decline in sensory function and new-onset paresthesia of her left foot.

An urgent consult to neurology was requested for nerve conduction studies. According to the electrodiagnostic study, the patient had a moderately severe left tibial neuropathy, likely at the popliteal fossa or distal to it. The nerve conduction study showed a chronic tibial nerve peripheral compressive mononeuropathy, and she was immediately scheduled for revision knee surgery with decompression of her Baker cyst to prevent further neurologic deficit.

During surgery, the knee joint exhibited hypertrophic synovitis with a characteristic pale-yellowish discoloration secondary to significant polyethylene wear disease (Figure 4). The polyethylene liner was severely worn with pitting, cracking, and delamination (Figure 5). While the patellar component was grossly loose, the tibial and femoral components were stable. After a complete synovectomy, the loose patellar component and tibial polyethylene liner were replaced. Osteolytic areas within the tibia underwent curettage and allograft impaction grafting. Lastly, decompression of the ruptured Baker cyst was performed via a 16-gauge needle placed in the posterior compartment of the left leg. The calf was gently squeezed with a “milking” maneuver, which yielded approximately 200 mL of thick, mucoid yellowish-brown synovial fluid resembling tapioca pudding (Figure 6).

Postoperatively, all intraoperative cultures were negative, and the patient was followed closely at 1 week, 2 weeks, 6 weeks, and 3 months after the surgery. At her latest follow-up, the posterior leg compartment remained decompressed and her progressive sensory deficit had nearly resolved. Moreover, the left leg and posterior knee pain completely resolved.

Discussion

A leading cause of TKA failure is attributed to aseptic loosening from polyethylene wear disease.² Implanted high-molecular-weight polyethylene (HMWPE) liners are known to undergo a variety of mechanical wear patterns within the knee. Observed patterns include pitting, scratching, burnishing, scratching, and delamination, which can all liberate numerous fine polyethylene particles.³ This wear debris induces macrophage phagocytosis that triggers an inflammatory reaction within the knee joint and can lead to synovitis, repeat effusions and, ultimately, to aseptic loosening.

Prior to 1996, polyethylene used in total knee replacement underwent a sterilization process in air. This oxygen-rich environment led to the development of free radical formation within the HMWPE. Ultimately, this had a detrimental effect on the polyethylene, leading to the formation of increased wear debris.⁴

Subsequently, orthopedic companies have changed their sterilization and manufacturing methods. Polyethylene components now undergo a variety of processes to eliminate or reduce oxidation, free-radical formation, and mechanical wear debris. Now, sterilization typically takes place in an inert atmospheric environment. Modern HMWPE implants often undergo higher irradiation to induce mechanical cross-linking, followed by either a re-annealing or remelting step. In other cases, manufacturers “dope” their polyethylene with vitamin E to quench free radicals within the material. While these steps have reduced the number of in vitro wear particles, the problem of wear debris, subsequent osteolysis, and aseptic loosening has not been eliminated.^1-5 

Polyethylene wear debris within the synovial fluid or tissue of failed TKAs can be identified with scanning electron microscopy or by light microscopy utilizing polarized light.¹ In this particular case, wear debris was confirmed within the synovial tissue and in the fluid of the Baker cyst by microscopic analysis.

Formation of a popliteal or Baker cyst as a result of polyethylene wear disease is an infrequent but known complication of TKA. Reports have demonstrated variable success in cyst eradication when revision surgery is performed on knees with synovial cysts. Most of these reports indicate that cyst formation tends to occur as a late complication (7 or more years) after TKA.^6-12

Treatment options may include skillful observation with close follow-up or revision surgery. Polyethylene exchange with synovectomy when feasible, as well as component revision with or without excision of the synovial cyst, are surgical options.

Niki and colleagues¹³ described a gigantic popliteal synovial cyst caused by wear particles after TKA. In this report, the surgeon performed a synovectomy and polyethylene liner exchange with retention of prosthetic components. At 12-month follow-up, the patient was reported to be doing well.

Mavrogenis and coauthors¹⁴ reported a wear debris–induced pseudotumor in the popliteal fossa and calf after TKA. In this case, in addition to the synovectomy, the surgeon removed all prosthetic components and used a semi-constrained implant to revise the knee. At 30-month follow-up, the patient reported having a painless knee.

While case reports have indicated that revision TKA for large, painful synovial cysts is a reasonable treatment option in carefully selected patients, there is a paucity of literature on this subject. Moreover, the present case appears to be the first literature report of a tibial nerve compressive neuropathy secondary to a synovial cyst after TKA.

Conclusion

In this report, polyethylene wear disease after TKA resulted in a massive synovial cyst extending into the posterior compartment of the leg. A progressive peripheral neuropathy confirmed by electromyography was also discovered. The patient underwent revision of a loose patellar component and worn polyethylene liner with complete synovectomy plus decompression of the cyst via needle aspiration. This resulted in an excellent short-term outcome with resolution of pain and significant improvement of the peripheral neuropathy 3 months after surgery.

Symptomatic synovial cyst formation is a rare, late occurrence after total knee arthroplasty (TKA); these cysts are generally discovered by chance. If they enlarge, they can result in significant pain and disability. A few case reports have described the development of very large cysts that required revision knee surgery. In this patient, polyethylene wear disease after TKA resulted in a massive synovial cyst that extended into the posterior compartment of the leg, as well as a progressive peripheral neuropathy. Revision of a loose patella component and worn polyethylene liner with complete synovectomy, plus decompression of the cyst via needle aspiration, resulted in an excellent short-term outcome.

To the author’s knowledge, this is the first case report of peripheral neuropathy of the tibial nerve secondary to a massive Baker cyst after total knee replacement. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

The patient was a 65-year-old woman with a complex medical history and multiple left knee surgeries, including a high tibial osteotomy and subsequent cemented TKA performed in the mid-1990s. She presented to the orthopedic department at a university hospital with complaints of knee pain 13 years after TKA. Observation was recommended; however, she was lost to follow-up.

The patient presented to her primary care physician (PCP) 16 years after TKA with a very large, painful mass in the back of her left leg. An ultrasound showed a large Baker cyst, and the patient was sent to interventional radiology. A few months later, she had an ultrasound-guided aspiration into the left calf, which produced 300 mL of thick synovial fluid. A cell count was not performed, but bacterial cultures were negative. Immediately after the aspiration, the pain was relieved.

Approximately 3 months after the aspiration, she presented again to her PCP with re-accumulation of fluid in the back of her left leg and severe leg pain. She was referred to a different orthopedic surgeon who determined that the risk of surgery was too great given her complex medical history.

The woman’s PCP referred the woman to our office 6 months after the aspiration. On presentation, her pain was localized to the posterior left leg. She reported the pain level as a constant 9 out of 10 on the visual analog scale, despite ingesting high doses of narcotics, including oxycontin and morphine. Her physical examination was remarkable for an ill-defined large calf mass. The posterior compartment of her left leg was firm and severely tender, similar to the characteristic findings seen in acute compartment syndrome.

Radiographs showed evidence of asymmetric polyethylene wear on the medial side of the knee (Figures 1A, 1B). Serum labs were ordered to evaluate for infection. C-reactive protein was mildly elevated at 5.5 mg/L (normal range, 0-5 mg/L); however, the erythrocyte sedimentation rate was normal at 12 mm/h (normal range, 0-20 mm/h). Magnetic resonance imaging of the left lower extremity with intravenous contrast showed the presence of a very large Baker cyst contained within the posterior compartment of the knee and a smaller surrounding cyst adjacent to the popliteal neurovascular bundle (Figure 2).

The Baker cyst was re-aspirated in the office. The automated synovial fluid cell count could not be performed because of high fluid viscosity. However, a manual review of the fluid specimen under light microscopy revealed proteinaceous, viscous tan-colored fluid containing no neutrophils and a few macrophages. Fluid cytology was also sent for review under polarizing light microscopy as described by Peterson and colleagues.¹ Scattered fragments of polarizable foreign material were consistent with polyethylene debris (Figure 3). 

The patient was counseled about the risks and benefits of surgery and was offered revision TKA with polyethylene liner exchange and synovectomy, only after complete cessation of smoking. She underwent serum nicotine monitoring to ensure tobacco cessation; however, she also reported the onset of a progressive sensory deficit over her left foot during this period. Although her medical history was remarkable for spinal stenosis, she noted a progressive decline in sensory function and new-onset paresthesia of her left foot.

An urgent consult to neurology was requested for nerve conduction studies. According to the electrodiagnostic study, the patient had a moderately severe left tibial neuropathy, likely at the popliteal fossa or distal to it. The nerve conduction study showed a chronic tibial nerve peripheral compressive mononeuropathy, and she was immediately scheduled for revision knee surgery with decompression of her Baker cyst to prevent further neurologic deficit.

During surgery, the knee joint exhibited hypertrophic synovitis with a characteristic pale-yellowish discoloration secondary to significant polyethylene wear disease (Figure 4). The polyethylene liner was severely worn with pitting, cracking, and delamination (Figure 5). While the patellar component was grossly loose, the tibial and femoral components were stable. After a complete synovectomy, the loose patellar component and tibial polyethylene liner were replaced. Osteolytic areas within the tibia underwent curettage and allograft impaction grafting. Lastly, decompression of the ruptured Baker cyst was performed via a 16-gauge needle placed in the posterior compartment of the left leg. The calf was gently squeezed with a “milking” maneuver, which yielded approximately 200 mL of thick, mucoid yellowish-brown synovial fluid resembling tapioca pudding (Figure 6).

Postoperatively, all intraoperative cultures were negative, and the patient was followed closely at 1 week, 2 weeks, 6 weeks, and 3 months after the surgery. At her latest follow-up, the posterior leg compartment remained decompressed and her progressive sensory deficit had nearly resolved. Moreover, the left leg and posterior knee pain completely resolved.

Discussion

A leading cause of TKA failure is attributed to aseptic loosening from polyethylene wear disease.² Implanted high-molecular-weight polyethylene (HMWPE) liners are known to undergo a variety of mechanical wear patterns within the knee. Observed patterns include pitting, scratching, burnishing, scratching, and delamination, which can all liberate numerous fine polyethylene particles.³ This wear debris induces macrophage phagocytosis that triggers an inflammatory reaction within the knee joint and can lead to synovitis, repeat effusions and, ultimately, to aseptic loosening.

Prior to 1996, polyethylene used in total knee replacement underwent a sterilization process in air. This oxygen-rich environment led to the development of free radical formation within the HMWPE. Ultimately, this had a detrimental effect on the polyethylene, leading to the formation of increased wear debris.⁴

Subsequently, orthopedic companies have changed their sterilization and manufacturing methods. Polyethylene components now undergo a variety of processes to eliminate or reduce oxidation, free-radical formation, and mechanical wear debris. Now, sterilization typically takes place in an inert atmospheric environment. Modern HMWPE implants often undergo higher irradiation to induce mechanical cross-linking, followed by either a re-annealing or remelting step. In other cases, manufacturers “dope” their polyethylene with vitamin E to quench free radicals within the material. While these steps have reduced the number of in vitro wear particles, the problem of wear debris, subsequent osteolysis, and aseptic loosening has not been eliminated.^1-5 

Polyethylene wear debris within the synovial fluid or tissue of failed TKAs can be identified with scanning electron microscopy or by light microscopy utilizing polarized light.¹ In this particular case, wear debris was confirmed within the synovial tissue and in the fluid of the Baker cyst by microscopic analysis.

Formation of a popliteal or Baker cyst as a result of polyethylene wear disease is an infrequent but known complication of TKA. Reports have demonstrated variable success in cyst eradication when revision surgery is performed on knees with synovial cysts. Most of these reports indicate that cyst formation tends to occur as a late complication (7 or more years) after TKA.^6-12

Treatment options may include skillful observation with close follow-up or revision surgery. Polyethylene exchange with synovectomy when feasible, as well as component revision with or without excision of the synovial cyst, are surgical options.

Niki and colleagues¹³ described a gigantic popliteal synovial cyst caused by wear particles after TKA. In this report, the surgeon performed a synovectomy and polyethylene liner exchange with retention of prosthetic components. At 12-month follow-up, the patient was reported to be doing well.

Mavrogenis and coauthors¹⁴ reported a wear debris–induced pseudotumor in the popliteal fossa and calf after TKA. In this case, in addition to the synovectomy, the surgeon removed all prosthetic components and used a semi-constrained implant to revise the knee. At 30-month follow-up, the patient reported having a painless knee.

While case reports have indicated that revision TKA for large, painful synovial cysts is a reasonable treatment option in carefully selected patients, there is a paucity of literature on this subject. Moreover, the present case appears to be the first literature report of a tibial nerve compressive neuropathy secondary to a synovial cyst after TKA.

Conclusion

In this report, polyethylene wear disease after TKA resulted in a massive synovial cyst extending into the posterior compartment of the leg. A progressive peripheral neuropathy confirmed by electromyography was also discovered. The patient underwent revision of a loose patellar component and worn polyethylene liner with complete synovectomy plus decompression of the cyst via needle aspiration. This resulted in an excellent short-term outcome with resolution of pain and significant improvement of the peripheral neuropathy 3 months after surgery.

Day Three highlights from HM15, the Society of Hospital Medicine’s (SHM) annual meeting in National Harbor, Md., just outside Washington, D.C.

Day Three highlights from HM15, the Society of Hospital Medicine’s (SHM) annual meeting in National Harbor, Md., just outside Washington, D.C.

Day Three highlights from HM15, the Society of Hospital Medicine’s (SHM) annual meeting in National Harbor, Md., just outside Washington, D.C.

Osteoarthritis is the most common joint disorder, resulting in significant morbidity and disability. The worldwide prevalence of osteoarthritis was estimated at more than 151 million people, according to data published in 2004.¹ In the United States, almost 27 million adults age 25 years and older suffer from clinically apparent disease.² The spine is one of the most commonly affected joints of arthritis, and idiopathic low back pain is the most frequent complaint in the adult population.³ In adults with low back pain, evidence of lumbar intervertebral disc degeneration is often found on radiography.⁴ In 1 study, evidence of disc degeneration was found in 90% of adults age 50 to 59 years.⁵

Degenerative spinal disease most commonly affects the lumbar spine due to its high degree of mobility and weight-loading.^6,7 Clinical^8,9 and experimental studies¹⁰ have suggested that the degenerative changes in the lumbar spine begin in the intervertebral discs. Degenerative disc disease (DDD) results from a continuum of dehydration, degradation, and remodeling of the intervertebral discs and neighboring vertebrae to accommodate the changes in physical loading.^11-13 This results in disc-space narrowing, disc bulging and herniation, vertebral rim osteophyte formation, and endplate sclerosis.^7,14 Symptomatic neural compression may occur, often manifested by localized lower back and extremity pain, as well as sensory loss and weakness of the lower extremities.^15-17 Changes in posture and gait may result because of altered sensation, and the consequent abnormal force transmission may predispose joints to accelerated wear and arthrosis.^15,18

Numerous studies have delineated the association between lumbar spinal disorders and lower extremity arthrosis. Of note, research has demonstrated that hip and/or knee pathology and gait alteration may promote low back pain and lumbar disc degeneration.^19-21 Although spinal abnormalities, such as scoliosis, may predispose an individual to accelerated hip degeneration,²⁰ no studies have investigated the relationship between lumbar DDD and ankle osteoarthritis.

Ankle arthritis differs from hip and knee arthritis demographically, occurring approximately 9 times less frequently.²¹ The ankle joint is subjected to more weight-bearing force per square centimeter and is more commonly injured than any other joint in the body.²¹ Trauma and/or abnormal ankle mechanics are the most common causes of degenerative ankle arthritis.²² Other potential causes include inflammatory arthropathies, neuropathic arthropathy, infection, and tumor. The purpose of this study was to determine if a relationship exists between ankle arthrosis and lumbar disc degeneration, and to delineate if one may promote the onset or progression of the other.

Materials and Methods

We randomly chose 710 cadaveric specimens from the Hamann-Todd Osteological Collection in Cleveland, Ohio. The Hamann-Todd Collection contains skeletal remains from more than 3000 individuals who died in Cleveland, Ohio between 1893 and 1938. The cohort for this study included 583 male and 127 female cadavers, ranging in age from 17 to 105 years at the time of death. Table 1 shows the breakdown of these specimens according to age group; of the 710 specimens, 306 were of African American ancestry, and 404 were Caucasian.

Lumbar DDD was graded at each lumbar spinal level by a single examiner using the Eubanks modification²³ of the Kettler and Wilke classification of vertebral endplate osteophytosis²⁴:

Grade 0: normal vertebral endplates;

Grade 1: mild arthrosis, with evidence of osteophytic reaction involving up to 50% of the vertebral endplates;

Grade 2: moderate arthrosis, with evidence of osteophytic reaction involving 50% to 100% of the vertebral endplates;

Grade 3: severe arthrosis, with evidence of osteophytic reaction involving 100% of the vertebral endplates. Osteophytes are hypertrophic and bridging the joint space (Figure 1);

Grade 4: complete ankylosis. 

Tibiotalar joint osteoarthritis was evaluated by a single examiner using a modification of the Kellgren-Lawrence classification⁴ for knee osteoarthritis:

Grade 0: no discernable wear/osteophytes;

Grade 1: 1-mm osteophyte(s) and/or <25% surface wear;

Grade 2: 1- to 2-mm osteophyte(s) and/or 25% to 50% joint surface;

Grade 3: 2- to 3-mm osteophyte(s) and/or >50% joint surface (Figure 2);

Grade 4: multiple large osteophytes and/or definite bony end deformity.

Statistical analysis was performed on the compiled data using Stata software (StataCorp, College Station, Texas). Linear and logistic regression analyses correcting for confounding factors of age, sex, race, and height were performed using a standard P-value cutoff (P < .05) and 95% confidence interval to determine statistical significance.

Results         

Patients were considered to have osteoarthritis of the tibiotalar joint if either of the extremities measured grade 1 or higher. Of the 710 specimens selected, 14 specimens did not have adequate bone available for bilateral tibiotalar joint measurement, either from extensive bone degradation or amputation. Of the remaining 696 specimens, 586 had some degree of tibiotalar osteoarthritis present (Table 2). Regression analysis showed a significant positive association between right- and left-ankle osteoarthritis (coefficient: 0.491, P < .01). Tibiotalar joint arthritis was classified as severe if either extremity had arthrosis of grade 3 or higher. Of the 586 specimens that had tibiotalar joint arthritis, only 16% (97 specimens) had severe tibiotalar joint arthritis.

Data regarding lumbar disc degeneration were available for 516 of the 710 specimens selected, 443 of which showed some disc degeneration. Disc degeneration was most prevalent and significant at the L4-L5 and L3-L4 intervertebral levels (Figures 3, 4). Of these 516 specimens, 30 had degeneration at 1 level, 47 specimens had degeneration at 2 levels, 29 specimens had degeneration at 3 levels, 52 had degeneration at 4 levels, and 285 specimens had degeneration at all 5 lumbar levels. The majority of specimens were found to have some degree of degeneration at all 5 lumbar spinal levels (Figure 5). Severe lumbar DDD was defined as grade 3 or higher osteoarthritis present in at least 1 of the 5 lumbar levels. Of the 516 specimens that showed some degree of disc degeneration, 152 were classified as severe. When stratified by number of spinal levels, only 30% of specimens were found to have evidence of severe arthrosis, the majority of which was located at only 1 lumbar segment (Figure 6).

Linear regression analysis of the data showed a statistically significant positive association between lumbar disc degeneration and tibiotalar osteoarthritis (coefficient: 0.844, P < .01), even when correcting for confounding factors, such as age, sex, and race (coefficient: 0.331, P < .01).

Additional analysis of the data demonstrated that tibiotalar joint arthritis remained significantly associated with lumbar DDD across each lumbar level: L1-L2 (coefficient: 0.269, P < .01), L2-L3 (coefficient: 0.283, P < .01), L3-L4 (coefficient: 0.299, P < .01), L4-L5 (coefficient: 0.240, P < .02), L5-S1 (coefficient: 0.167, P < .05).

The presence of 3 or more levels of lumbar DDD significantly increased the possibility of developing severe tibiotalar joint arthritis. Lumbar DDD that encompassed 3 levels showed the highest odds for development of severe tibiotalar joint arthritis with an odds ratio (OR) of 20.542 (Table 3).

When subjects were compared by decade, the mean grade of tibiotalar joint arthritis was significantly higher than lumbar DDD in specimens who died in their 20s and 30s. This difference was insignificant in the fourth decade, and thereafter the mean value of lumbar DDD surpassed that of tibiotalar joint arthritis (Figure 7).

In contrast, severe lumbar DDD was more prevalent than severe tibiotalar joint arthritis in individuals age 20 years or older (Figure 8). There were no specimens under age 20 years with severe lumbar DDD or severe tibiotalar joint arthritis.

Logistic regression showed that individuals with severe lumbar disc degeneration had significantly higher odds of developing severe ankle arthritis (OR: 1.93, P < .05). Similarly, individuals with severe tibiotalar joint arthritis were just as likely to develop severe lumbar DDD with an OR of 1.97 (P < .05).

Discussion

Multiple joint involvement in osteoarthritis is well established with a wide range of evidence linking lower extremity joint pathology and lumbar spinal disease. In 1983, Offierski and MacNab²⁰ were the first to describe hip-spine syndrome. In the next year, a study by Sponseller and colleagues²⁵ of pediatric patients after hip arthrodesis further substantiated the association between spine and extremity disease, and demonstrated a continued cause and effect relationship after surgery.

Lumbar spinal degeneration has also been correlated with knee osteoarthritis. Tsuji and colleagues²⁶ reported that degenerative changes in spinal alignment result in increased thigh muscle tension and knee flexion. Furthermore, in their radiographic analysis of 682 individuals, Horvath and colleagues²⁷ also showed that individuals with spinal degeneration had a higher prevalence of knee and hip osteoarthritis.

One might hypothesize from this evidence that lumbar spinal degeneration and ankle arthritis would also be interrelated, given their interconnected role in lower extremity force transmission. Surprisingly, the literature correlating lumbar degeneration and lower extremity osteoarthritis has overlooked this association and has focused solely on the hip and knee. To our knowledge, this study is the first to identify a statistically significant association between tibiotalar joint osteoarthritis and lumbar disc degeneration.

The literature supported analysis of our data. Miller and colleagues²⁸ evaluated disc degeneration in 600 autopsy specimens using the Nachemson²⁹ grading system. This system categorizes disc degeneration into 4 grades based on macroscopic appearance. Miller and colleagues²⁸ reported evidence of degenerative changes as early as the second decade of life, primarily involving the L3–L4 and L4–L5 levels. Of note, the Nachemson²⁹ classification system includes only evidence of marginal osteophytes in grade 4 disease, which was not identified by Miller and colleagues²⁸ until the fourth decade. These results were similar to those in our study, in which the L3-L4 and L4-L5 intervertebral levels were most commonly affected. However, in our study, significant degenerative changes were found in the third decade of life. 

In addition, the percentage of specimens with severe disc degeneration increased with each decade (Figure 8). A substantial amount of histologic evidence demonstrates the progression of disc degeneration with age. With increased age, there is a gradual decrease in the osmotic swelling of intervertebral discs³⁰ and a 2-fold decrease in disc hydration between adolescence and the eighth decade.³¹ Furthermore, the nucleus pulposus undergoes progressive fibrosis,^32,33 with a 5-fold decrease in the fixed-charge density of nucleus glycosaminoglycans,³⁴ and a 2-fold increase in intervertebral disc creep while under compression after age 30 years.³⁵

While analyzing our findings, we had difficulty in determining which pathologic condition debuts and, subsequently, affects the other. According to our results, the mean grade of tibiotalar joint arthritis was higher than that of DDD in specimens through the third and fourth decades of life (Figure 7). After the age of 50 years, the mean grade of DDD surpasses that of tibiotalar arthritis. This may be initially interpreted that development of tibiotalar joint arthritis precedes lumbar disc degeneration. Ankle osteoarthritis is relatively rare, and given that the vast majority of ankle osteoarthritis is secondary to trauma,²² we would expect to see a higher incidence of ankle osteoarthritis in a younger, more active cohort. In addition, given our finding that ankle arthritis is related to lumbar disc degeneration, one could speculate that tibiotalar arthritis at a young age predisposes an individual to developing lumbar degeneration later in life.

However, this conclusion is inherently flawed; closer examination of the data revealed that the mean grade of tibiotalar arthritis and DDD in the third and fourth decades is relatively low, between grade 0 and grade 1 (Figure 7). Therefore, it is difficult to arrive at a conclusion when comparing such small values. Second, we must remember that we are comparing an average value of disc degeneration across all lumbar levels. When a specimen has only 1 disc that is severely degenerated, this value is averaged across all 5 lumbar levels and, thus, the overall mean grade of arthrosis is significantly diminished.

In fact, data from previous studies concur with the second argument. Upper-level lumbar disc degeneration is relatively rare and the vast majority of patients with disc degeneration present with significant disease in only 1 or 2 discs.^36,37 Analysis of the specimens in this study revealed bony evidence of disc degeneration present at all 5 lumbar levels in over half of the specimens examined (57%). However, the majority of specimens in this cohort exhibit only low-grade degeneration. When specimens were analyzed for severe arthrosis (grade 3 and higher), nearly half of the specimens were found to have severe disease involving only 1 intervertebral disc (Figure 6). Data from Miller and colleagues²⁸ and the present study show that the upper lumbar levels were relatively spared; the L3-L4 and L4-L5 lumbar levels showed the highest prevalence and severity of degenerative change.

To address this issue, we evaluated the percentage of specimens per decade with severe arthrosis (grade 3 and higher) of at least 1 lumbar intervertebral disc and 1 tibiotalar joint. Severe lumbar disc degeneration was found to be more prevalent than severe ankle arthritis in individuals age 20 years or older (Figure 8). Therefore, we postulate that significant degenerative changes in the lumbar spine precede the development of severe ankle arthritis.

One can further speculate that sequelae from lumbar disc degeneration may lead to the development of tibiotalar arthritis, given our finding that severe lumbar degeneration predisposes an individual to the development of ankle arthritis. Because significant lumbar disc degeneration has long been known to result in both spinal nerve and cord compression, we hypothesize that this resultant neurocompression promotes altered gait and translation of atypical forces to the ankle and foot, thus predisposing to the onset and/or progression of osteoarthritis. In support of this hypothesis, Morag and colleagues¹⁵ demonstrated that neurologic compression produced an altered posture and gait because of lost motor function and afferent proprioceptive sensation. This form of neurologic compromise may exert atypical forces upon the foot and ankle, predisposing the joint to accelerated wear and primary arthrosis.

In addition, DDD involving 3 or more lumbar intervertebral levels was found to significantly increase the likelihood of the subject having severe tibiotalar joint arthritis. Provided that lumbar disc degeneration typically involves significant degeneration at 1 level, we assume that significant arthrosis at 3 or more levels correlates to an overall more severe DDD with a higher corresponding likelihood of neural compression. However, compression of peripheral lower extremity nerves has been shown to result in neuropathic arthropathy akin to the diabetic Charcot foot.³⁸ This could be a possible mechanism of accelerated ankle arthritis, but this study did not examine soft-tissue disease nor take into account other medical comorbidities of each specimen, including genetic predispositions towards osteoarthritis.

It should be noted that the aforementioned causative relationship between lumbar disc degeneration and tibiotalar arthritis is speculative and cannot be demonstrated definitively by this investigation. We acknowledge limitations of this study and the need for further research of the possible causative mechanism(s) of accelerated ankle arthrosis secondary to lumbar spinal disease. Ideally, the questions posed by our report would be answered via a large prospective cohort study that utilized both serial imaging and autopsy analysis. Unfortunately, this form of study is logistically and financially difficult to perform.

This was a retrospective cadaveric study in which determination of arthrosis severity was based solely on bony evidence. Therefore, the role of soft-tissue disease in the pathogenesis of arthrosis of the lumbar spine and tibiotalar joint could not be assessed, nor could definitive associations to clinically symptomatic disease. We made the assumption that progression of bone degeneration in both the lumbar spine and tibiotalar joint corresponded equally to the associated soft-tissue changes. Given this assumption, we cannot definitively conclude that degeneration of the lumbar spine precedes that of the ankle, because the absence of magnetic resonance imaging or fresh autopsy specimens in our study misses the early degenerative changes in the discs that precede the bony alteration measured in our study. Furthermore, readers should note that since this study compared only bone morphology, no emphasis was placed on clinical manifestation of lumbar disc degeneration or tibiotalar joint arthritis. As mentioned earlier, radiologic evidence of disc degeneration was found in 90% of adults age 50 to 59 years, according to a study by Hult⁵; however, it is important to note that not all individuals studied were symptomatic clinically. Unfortunately, medical records were not available for the bony specimens, and clinical correlations could not be assessed during this investigation.

Furthermore, no special attention was given to other pathologic conditions observed during specimen measurement. The presence of diseases, such as osteoporosis, spondylolysis, or previous traumatic injury, may have had implications in the resultant joint degeneration. Finally, the evaluation of arthrosis was performed subjectively without measuring reliability. However, the present analysis includes a large sample, each joint type was reviewed by a single examiner, and used a classification system that was modeled on a validated grading system. Ideally, multiple individuals should have been used for each type of measurement, with subsequent analysis of intraobserver and interobserver reliability.

Conclusion

Based on our study of a large population of adult skeletal specimens, we ascertained that lumbar intervertebral disc degeneration and tibiotalar osteoarthritis are associated. The prevalence of severe lumbar disc degeneration was higher than that of tibiotalar joint arthritis in individuals age 20 years or older. This may suggest that gait changes from disc degeneration or neural compression in the lumbar spine may play a role in the development of ankle osteoarthritis. Additionally, subjects with severe disc degeneration were twice as likely to develop significant tibiotalar osteoarthritis. This must be considered in the differential when treating patients with degenerative changes of the lumbar spine and leg pain.

Osteoarthritis is the most common joint disorder, resulting in significant morbidity and disability. The worldwide prevalence of osteoarthritis was estimated at more than 151 million people, according to data published in 2004.¹ In the United States, almost 27 million adults age 25 years and older suffer from clinically apparent disease.² The spine is one of the most commonly affected joints of arthritis, and idiopathic low back pain is the most frequent complaint in the adult population.³ In adults with low back pain, evidence of lumbar intervertebral disc degeneration is often found on radiography.⁴ In 1 study, evidence of disc degeneration was found in 90% of adults age 50 to 59 years.⁵

Degenerative spinal disease most commonly affects the lumbar spine due to its high degree of mobility and weight-loading.^6,7 Clinical^8,9 and experimental studies¹⁰ have suggested that the degenerative changes in the lumbar spine begin in the intervertebral discs. Degenerative disc disease (DDD) results from a continuum of dehydration, degradation, and remodeling of the intervertebral discs and neighboring vertebrae to accommodate the changes in physical loading.^11-13 This results in disc-space narrowing, disc bulging and herniation, vertebral rim osteophyte formation, and endplate sclerosis.^7,14 Symptomatic neural compression may occur, often manifested by localized lower back and extremity pain, as well as sensory loss and weakness of the lower extremities.^15-17 Changes in posture and gait may result because of altered sensation, and the consequent abnormal force transmission may predispose joints to accelerated wear and arthrosis.^15,18

Numerous studies have delineated the association between lumbar spinal disorders and lower extremity arthrosis. Of note, research has demonstrated that hip and/or knee pathology and gait alteration may promote low back pain and lumbar disc degeneration.^19-21 Although spinal abnormalities, such as scoliosis, may predispose an individual to accelerated hip degeneration,²⁰ no studies have investigated the relationship between lumbar DDD and ankle osteoarthritis.

Ankle arthritis differs from hip and knee arthritis demographically, occurring approximately 9 times less frequently.²¹ The ankle joint is subjected to more weight-bearing force per square centimeter and is more commonly injured than any other joint in the body.²¹ Trauma and/or abnormal ankle mechanics are the most common causes of degenerative ankle arthritis.²² Other potential causes include inflammatory arthropathies, neuropathic arthropathy, infection, and tumor. The purpose of this study was to determine if a relationship exists between ankle arthrosis and lumbar disc degeneration, and to delineate if one may promote the onset or progression of the other.

Materials and Methods

We randomly chose 710 cadaveric specimens from the Hamann-Todd Osteological Collection in Cleveland, Ohio. The Hamann-Todd Collection contains skeletal remains from more than 3000 individuals who died in Cleveland, Ohio between 1893 and 1938. The cohort for this study included 583 male and 127 female cadavers, ranging in age from 17 to 105 years at the time of death. Table 1 shows the breakdown of these specimens according to age group; of the 710 specimens, 306 were of African American ancestry, and 404 were Caucasian.

Lumbar DDD was graded at each lumbar spinal level by a single examiner using the Eubanks modification²³ of the Kettler and Wilke classification of vertebral endplate osteophytosis²⁴:

Grade 0: normal vertebral endplates;

Grade 1: mild arthrosis, with evidence of osteophytic reaction involving up to 50% of the vertebral endplates;

Grade 2: moderate arthrosis, with evidence of osteophytic reaction involving 50% to 100% of the vertebral endplates;

Grade 3: severe arthrosis, with evidence of osteophytic reaction involving 100% of the vertebral endplates. Osteophytes are hypertrophic and bridging the joint space (Figure 1);

Grade 4: complete ankylosis. 

Tibiotalar joint osteoarthritis was evaluated by a single examiner using a modification of the Kellgren-Lawrence classification⁴ for knee osteoarthritis:

Grade 0: no discernable wear/osteophytes;

Grade 1: 1-mm osteophyte(s) and/or <25% surface wear;

Grade 2: 1- to 2-mm osteophyte(s) and/or 25% to 50% joint surface;

Grade 3: 2- to 3-mm osteophyte(s) and/or >50% joint surface (Figure 2);

Grade 4: multiple large osteophytes and/or definite bony end deformity.

Statistical analysis was performed on the compiled data using Stata software (StataCorp, College Station, Texas). Linear and logistic regression analyses correcting for confounding factors of age, sex, race, and height were performed using a standard P-value cutoff (P < .05) and 95% confidence interval to determine statistical significance.

Results         

Patients were considered to have osteoarthritis of the tibiotalar joint if either of the extremities measured grade 1 or higher. Of the 710 specimens selected, 14 specimens did not have adequate bone available for bilateral tibiotalar joint measurement, either from extensive bone degradation or amputation. Of the remaining 696 specimens, 586 had some degree of tibiotalar osteoarthritis present (Table 2). Regression analysis showed a significant positive association between right- and left-ankle osteoarthritis (coefficient: 0.491, P < .01). Tibiotalar joint arthritis was classified as severe if either extremity had arthrosis of grade 3 or higher. Of the 586 specimens that had tibiotalar joint arthritis, only 16% (97 specimens) had severe tibiotalar joint arthritis.

Data regarding lumbar disc degeneration were available for 516 of the 710 specimens selected, 443 of which showed some disc degeneration. Disc degeneration was most prevalent and significant at the L4-L5 and L3-L4 intervertebral levels (Figures 3, 4). Of these 516 specimens, 30 had degeneration at 1 level, 47 specimens had degeneration at 2 levels, 29 specimens had degeneration at 3 levels, 52 had degeneration at 4 levels, and 285 specimens had degeneration at all 5 lumbar levels. The majority of specimens were found to have some degree of degeneration at all 5 lumbar spinal levels (Figure 5). Severe lumbar DDD was defined as grade 3 or higher osteoarthritis present in at least 1 of the 5 lumbar levels. Of the 516 specimens that showed some degree of disc degeneration, 152 were classified as severe. When stratified by number of spinal levels, only 30% of specimens were found to have evidence of severe arthrosis, the majority of which was located at only 1 lumbar segment (Figure 6).

Linear regression analysis of the data showed a statistically significant positive association between lumbar disc degeneration and tibiotalar osteoarthritis (coefficient: 0.844, P < .01), even when correcting for confounding factors, such as age, sex, and race (coefficient: 0.331, P < .01).

Additional analysis of the data demonstrated that tibiotalar joint arthritis remained significantly associated with lumbar DDD across each lumbar level: L1-L2 (coefficient: 0.269, P < .01), L2-L3 (coefficient: 0.283, P < .01), L3-L4 (coefficient: 0.299, P < .01), L4-L5 (coefficient: 0.240, P < .02), L5-S1 (coefficient: 0.167, P < .05).

The presence of 3 or more levels of lumbar DDD significantly increased the possibility of developing severe tibiotalar joint arthritis. Lumbar DDD that encompassed 3 levels showed the highest odds for development of severe tibiotalar joint arthritis with an odds ratio (OR) of 20.542 (Table 3).

When subjects were compared by decade, the mean grade of tibiotalar joint arthritis was significantly higher than lumbar DDD in specimens who died in their 20s and 30s. This difference was insignificant in the fourth decade, and thereafter the mean value of lumbar DDD surpassed that of tibiotalar joint arthritis (Figure 7).

In contrast, severe lumbar DDD was more prevalent than severe tibiotalar joint arthritis in individuals age 20 years or older (Figure 8). There were no specimens under age 20 years with severe lumbar DDD or severe tibiotalar joint arthritis.

Logistic regression showed that individuals with severe lumbar disc degeneration had significantly higher odds of developing severe ankle arthritis (OR: 1.93, P < .05). Similarly, individuals with severe tibiotalar joint arthritis were just as likely to develop severe lumbar DDD with an OR of 1.97 (P < .05).

Discussion

Multiple joint involvement in osteoarthritis is well established with a wide range of evidence linking lower extremity joint pathology and lumbar spinal disease. In 1983, Offierski and MacNab²⁰ were the first to describe hip-spine syndrome. In the next year, a study by Sponseller and colleagues²⁵ of pediatric patients after hip arthrodesis further substantiated the association between spine and extremity disease, and demonstrated a continued cause and effect relationship after surgery.

Lumbar spinal degeneration has also been correlated with knee osteoarthritis. Tsuji and colleagues²⁶ reported that degenerative changes in spinal alignment result in increased thigh muscle tension and knee flexion. Furthermore, in their radiographic analysis of 682 individuals, Horvath and colleagues²⁷ also showed that individuals with spinal degeneration had a higher prevalence of knee and hip osteoarthritis.

One might hypothesize from this evidence that lumbar spinal degeneration and ankle arthritis would also be interrelated, given their interconnected role in lower extremity force transmission. Surprisingly, the literature correlating lumbar degeneration and lower extremity osteoarthritis has overlooked this association and has focused solely on the hip and knee. To our knowledge, this study is the first to identify a statistically significant association between tibiotalar joint osteoarthritis and lumbar disc degeneration.

The literature supported analysis of our data. Miller and colleagues²⁸ evaluated disc degeneration in 600 autopsy specimens using the Nachemson²⁹ grading system. This system categorizes disc degeneration into 4 grades based on macroscopic appearance. Miller and colleagues²⁸ reported evidence of degenerative changes as early as the second decade of life, primarily involving the L3–L4 and L4–L5 levels. Of note, the Nachemson²⁹ classification system includes only evidence of marginal osteophytes in grade 4 disease, which was not identified by Miller and colleagues²⁸ until the fourth decade. These results were similar to those in our study, in which the L3-L4 and L4-L5 intervertebral levels were most commonly affected. However, in our study, significant degenerative changes were found in the third decade of life. 

In addition, the percentage of specimens with severe disc degeneration increased with each decade (Figure 8). A substantial amount of histologic evidence demonstrates the progression of disc degeneration with age. With increased age, there is a gradual decrease in the osmotic swelling of intervertebral discs³⁰ and a 2-fold decrease in disc hydration between adolescence and the eighth decade.³¹ Furthermore, the nucleus pulposus undergoes progressive fibrosis,^32,33 with a 5-fold decrease in the fixed-charge density of nucleus glycosaminoglycans,³⁴ and a 2-fold increase in intervertebral disc creep while under compression after age 30 years.³⁵

While analyzing our findings, we had difficulty in determining which pathologic condition debuts and, subsequently, affects the other. According to our results, the mean grade of tibiotalar joint arthritis was higher than that of DDD in specimens through the third and fourth decades of life (Figure 7). After the age of 50 years, the mean grade of DDD surpasses that of tibiotalar arthritis. This may be initially interpreted that development of tibiotalar joint arthritis precedes lumbar disc degeneration. Ankle osteoarthritis is relatively rare, and given that the vast majority of ankle osteoarthritis is secondary to trauma,²² we would expect to see a higher incidence of ankle osteoarthritis in a younger, more active cohort. In addition, given our finding that ankle arthritis is related to lumbar disc degeneration, one could speculate that tibiotalar arthritis at a young age predisposes an individual to developing lumbar degeneration later in life.

However, this conclusion is inherently flawed; closer examination of the data revealed that the mean grade of tibiotalar arthritis and DDD in the third and fourth decades is relatively low, between grade 0 and grade 1 (Figure 7). Therefore, it is difficult to arrive at a conclusion when comparing such small values. Second, we must remember that we are comparing an average value of disc degeneration across all lumbar levels. When a specimen has only 1 disc that is severely degenerated, this value is averaged across all 5 lumbar levels and, thus, the overall mean grade of arthrosis is significantly diminished.

In fact, data from previous studies concur with the second argument. Upper-level lumbar disc degeneration is relatively rare and the vast majority of patients with disc degeneration present with significant disease in only 1 or 2 discs.^36,37 Analysis of the specimens in this study revealed bony evidence of disc degeneration present at all 5 lumbar levels in over half of the specimens examined (57%). However, the majority of specimens in this cohort exhibit only low-grade degeneration. When specimens were analyzed for severe arthrosis (grade 3 and higher), nearly half of the specimens were found to have severe disease involving only 1 intervertebral disc (Figure 6). Data from Miller and colleagues²⁸ and the present study show that the upper lumbar levels were relatively spared; the L3-L4 and L4-L5 lumbar levels showed the highest prevalence and severity of degenerative change.

To address this issue, we evaluated the percentage of specimens per decade with severe arthrosis (grade 3 and higher) of at least 1 lumbar intervertebral disc and 1 tibiotalar joint. Severe lumbar disc degeneration was found to be more prevalent than severe ankle arthritis in individuals age 20 years or older (Figure 8). Therefore, we postulate that significant degenerative changes in the lumbar spine precede the development of severe ankle arthritis.

One can further speculate that sequelae from lumbar disc degeneration may lead to the development of tibiotalar arthritis, given our finding that severe lumbar degeneration predisposes an individual to the development of ankle arthritis. Because significant lumbar disc degeneration has long been known to result in both spinal nerve and cord compression, we hypothesize that this resultant neurocompression promotes altered gait and translation of atypical forces to the ankle and foot, thus predisposing to the onset and/or progression of osteoarthritis. In support of this hypothesis, Morag and colleagues¹⁵ demonstrated that neurologic compression produced an altered posture and gait because of lost motor function and afferent proprioceptive sensation. This form of neurologic compromise may exert atypical forces upon the foot and ankle, predisposing the joint to accelerated wear and primary arthrosis.

In addition, DDD involving 3 or more lumbar intervertebral levels was found to significantly increase the likelihood of the subject having severe tibiotalar joint arthritis. Provided that lumbar disc degeneration typically involves significant degeneration at 1 level, we assume that significant arthrosis at 3 or more levels correlates to an overall more severe DDD with a higher corresponding likelihood of neural compression. However, compression of peripheral lower extremity nerves has been shown to result in neuropathic arthropathy akin to the diabetic Charcot foot.³⁸ This could be a possible mechanism of accelerated ankle arthritis, but this study did not examine soft-tissue disease nor take into account other medical comorbidities of each specimen, including genetic predispositions towards osteoarthritis.

It should be noted that the aforementioned causative relationship between lumbar disc degeneration and tibiotalar arthritis is speculative and cannot be demonstrated definitively by this investigation. We acknowledge limitations of this study and the need for further research of the possible causative mechanism(s) of accelerated ankle arthrosis secondary to lumbar spinal disease. Ideally, the questions posed by our report would be answered via a large prospective cohort study that utilized both serial imaging and autopsy analysis. Unfortunately, this form of study is logistically and financially difficult to perform.

This was a retrospective cadaveric study in which determination of arthrosis severity was based solely on bony evidence. Therefore, the role of soft-tissue disease in the pathogenesis of arthrosis of the lumbar spine and tibiotalar joint could not be assessed, nor could definitive associations to clinically symptomatic disease. We made the assumption that progression of bone degeneration in both the lumbar spine and tibiotalar joint corresponded equally to the associated soft-tissue changes. Given this assumption, we cannot definitively conclude that degeneration of the lumbar spine precedes that of the ankle, because the absence of magnetic resonance imaging or fresh autopsy specimens in our study misses the early degenerative changes in the discs that precede the bony alteration measured in our study. Furthermore, readers should note that since this study compared only bone morphology, no emphasis was placed on clinical manifestation of lumbar disc degeneration or tibiotalar joint arthritis. As mentioned earlier, radiologic evidence of disc degeneration was found in 90% of adults age 50 to 59 years, according to a study by Hult⁵; however, it is important to note that not all individuals studied were symptomatic clinically. Unfortunately, medical records were not available for the bony specimens, and clinical correlations could not be assessed during this investigation.

Furthermore, no special attention was given to other pathologic conditions observed during specimen measurement. The presence of diseases, such as osteoporosis, spondylolysis, or previous traumatic injury, may have had implications in the resultant joint degeneration. Finally, the evaluation of arthrosis was performed subjectively without measuring reliability. However, the present analysis includes a large sample, each joint type was reviewed by a single examiner, and used a classification system that was modeled on a validated grading system. Ideally, multiple individuals should have been used for each type of measurement, with subsequent analysis of intraobserver and interobserver reliability.

Conclusion

Based on our study of a large population of adult skeletal specimens, we ascertained that lumbar intervertebral disc degeneration and tibiotalar osteoarthritis are associated. The prevalence of severe lumbar disc degeneration was higher than that of tibiotalar joint arthritis in individuals age 20 years or older. This may suggest that gait changes from disc degeneration or neural compression in the lumbar spine may play a role in the development of ankle osteoarthritis. Additionally, subjects with severe disc degeneration were twice as likely to develop significant tibiotalar osteoarthritis. This must be considered in the differential when treating patients with degenerative changes of the lumbar spine and leg pain.

Osteoarthritis is the most common joint disorder, resulting in significant morbidity and disability. The worldwide prevalence of osteoarthritis was estimated at more than 151 million people, according to data published in 2004.¹ In the United States, almost 27 million adults age 25 years and older suffer from clinically apparent disease.² The spine is one of the most commonly affected joints of arthritis, and idiopathic low back pain is the most frequent complaint in the adult population.³ In adults with low back pain, evidence of lumbar intervertebral disc degeneration is often found on radiography.⁴ In 1 study, evidence of disc degeneration was found in 90% of adults age 50 to 59 years.⁵

Degenerative spinal disease most commonly affects the lumbar spine due to its high degree of mobility and weight-loading.^6,7 Clinical^8,9 and experimental studies¹⁰ have suggested that the degenerative changes in the lumbar spine begin in the intervertebral discs. Degenerative disc disease (DDD) results from a continuum of dehydration, degradation, and remodeling of the intervertebral discs and neighboring vertebrae to accommodate the changes in physical loading.^11-13 This results in disc-space narrowing, disc bulging and herniation, vertebral rim osteophyte formation, and endplate sclerosis.^7,14 Symptomatic neural compression may occur, often manifested by localized lower back and extremity pain, as well as sensory loss and weakness of the lower extremities.^15-17 Changes in posture and gait may result because of altered sensation, and the consequent abnormal force transmission may predispose joints to accelerated wear and arthrosis.^15,18

Numerous studies have delineated the association between lumbar spinal disorders and lower extremity arthrosis. Of note, research has demonstrated that hip and/or knee pathology and gait alteration may promote low back pain and lumbar disc degeneration.^19-21 Although spinal abnormalities, such as scoliosis, may predispose an individual to accelerated hip degeneration,²⁰ no studies have investigated the relationship between lumbar DDD and ankle osteoarthritis.

Ankle arthritis differs from hip and knee arthritis demographically, occurring approximately 9 times less frequently.²¹ The ankle joint is subjected to more weight-bearing force per square centimeter and is more commonly injured than any other joint in the body.²¹ Trauma and/or abnormal ankle mechanics are the most common causes of degenerative ankle arthritis.²² Other potential causes include inflammatory arthropathies, neuropathic arthropathy, infection, and tumor. The purpose of this study was to determine if a relationship exists between ankle arthrosis and lumbar disc degeneration, and to delineate if one may promote the onset or progression of the other.

Materials and Methods

We randomly chose 710 cadaveric specimens from the Hamann-Todd Osteological Collection in Cleveland, Ohio. The Hamann-Todd Collection contains skeletal remains from more than 3000 individuals who died in Cleveland, Ohio between 1893 and 1938. The cohort for this study included 583 male and 127 female cadavers, ranging in age from 17 to 105 years at the time of death. Table 1 shows the breakdown of these specimens according to age group; of the 710 specimens, 306 were of African American ancestry, and 404 were Caucasian.

Lumbar DDD was graded at each lumbar spinal level by a single examiner using the Eubanks modification²³ of the Kettler and Wilke classification of vertebral endplate osteophytosis²⁴:

Grade 0: normal vertebral endplates;

Grade 1: mild arthrosis, with evidence of osteophytic reaction involving up to 50% of the vertebral endplates;

Grade 2: moderate arthrosis, with evidence of osteophytic reaction involving 50% to 100% of the vertebral endplates;

Grade 3: severe arthrosis, with evidence of osteophytic reaction involving 100% of the vertebral endplates. Osteophytes are hypertrophic and bridging the joint space (Figure 1);

Grade 4: complete ankylosis. 

Tibiotalar joint osteoarthritis was evaluated by a single examiner using a modification of the Kellgren-Lawrence classification⁴ for knee osteoarthritis:

Grade 0: no discernable wear/osteophytes;

Grade 1: 1-mm osteophyte(s) and/or <25% surface wear;

Grade 2: 1- to 2-mm osteophyte(s) and/or 25% to 50% joint surface;

Grade 3: 2- to 3-mm osteophyte(s) and/or >50% joint surface (Figure 2);

Grade 4: multiple large osteophytes and/or definite bony end deformity.

Statistical analysis was performed on the compiled data using Stata software (StataCorp, College Station, Texas). Linear and logistic regression analyses correcting for confounding factors of age, sex, race, and height were performed using a standard P-value cutoff (P < .05) and 95% confidence interval to determine statistical significance.

Results         

Patients were considered to have osteoarthritis of the tibiotalar joint if either of the extremities measured grade 1 or higher. Of the 710 specimens selected, 14 specimens did not have adequate bone available for bilateral tibiotalar joint measurement, either from extensive bone degradation or amputation. Of the remaining 696 specimens, 586 had some degree of tibiotalar osteoarthritis present (Table 2). Regression analysis showed a significant positive association between right- and left-ankle osteoarthritis (coefficient: 0.491, P < .01). Tibiotalar joint arthritis was classified as severe if either extremity had arthrosis of grade 3 or higher. Of the 586 specimens that had tibiotalar joint arthritis, only 16% (97 specimens) had severe tibiotalar joint arthritis.

Data regarding lumbar disc degeneration were available for 516 of the 710 specimens selected, 443 of which showed some disc degeneration. Disc degeneration was most prevalent and significant at the L4-L5 and L3-L4 intervertebral levels (Figures 3, 4). Of these 516 specimens, 30 had degeneration at 1 level, 47 specimens had degeneration at 2 levels, 29 specimens had degeneration at 3 levels, 52 had degeneration at 4 levels, and 285 specimens had degeneration at all 5 lumbar levels. The majority of specimens were found to have some degree of degeneration at all 5 lumbar spinal levels (Figure 5). Severe lumbar DDD was defined as grade 3 or higher osteoarthritis present in at least 1 of the 5 lumbar levels. Of the 516 specimens that showed some degree of disc degeneration, 152 were classified as severe. When stratified by number of spinal levels, only 30% of specimens were found to have evidence of severe arthrosis, the majority of which was located at only 1 lumbar segment (Figure 6).

Linear regression analysis of the data showed a statistically significant positive association between lumbar disc degeneration and tibiotalar osteoarthritis (coefficient: 0.844, P < .01), even when correcting for confounding factors, such as age, sex, and race (coefficient: 0.331, P < .01).

Additional analysis of the data demonstrated that tibiotalar joint arthritis remained significantly associated with lumbar DDD across each lumbar level: L1-L2 (coefficient: 0.269, P < .01), L2-L3 (coefficient: 0.283, P < .01), L3-L4 (coefficient: 0.299, P < .01), L4-L5 (coefficient: 0.240, P < .02), L5-S1 (coefficient: 0.167, P < .05).

The presence of 3 or more levels of lumbar DDD significantly increased the possibility of developing severe tibiotalar joint arthritis. Lumbar DDD that encompassed 3 levels showed the highest odds for development of severe tibiotalar joint arthritis with an odds ratio (OR) of 20.542 (Table 3).

When subjects were compared by decade, the mean grade of tibiotalar joint arthritis was significantly higher than lumbar DDD in specimens who died in their 20s and 30s. This difference was insignificant in the fourth decade, and thereafter the mean value of lumbar DDD surpassed that of tibiotalar joint arthritis (Figure 7).

In contrast, severe lumbar DDD was more prevalent than severe tibiotalar joint arthritis in individuals age 20 years or older (Figure 8). There were no specimens under age 20 years with severe lumbar DDD or severe tibiotalar joint arthritis.

Logistic regression showed that individuals with severe lumbar disc degeneration had significantly higher odds of developing severe ankle arthritis (OR: 1.93, P < .05). Similarly, individuals with severe tibiotalar joint arthritis were just as likely to develop severe lumbar DDD with an OR of 1.97 (P < .05).

Discussion

Multiple joint involvement in osteoarthritis is well established with a wide range of evidence linking lower extremity joint pathology and lumbar spinal disease. In 1983, Offierski and MacNab²⁰ were the first to describe hip-spine syndrome. In the next year, a study by Sponseller and colleagues²⁵ of pediatric patients after hip arthrodesis further substantiated the association between spine and extremity disease, and demonstrated a continued cause and effect relationship after surgery.

Lumbar spinal degeneration has also been correlated with knee osteoarthritis. Tsuji and colleagues²⁶ reported that degenerative changes in spinal alignment result in increased thigh muscle tension and knee flexion. Furthermore, in their radiographic analysis of 682 individuals, Horvath and colleagues²⁷ also showed that individuals with spinal degeneration had a higher prevalence of knee and hip osteoarthritis.

One might hypothesize from this evidence that lumbar spinal degeneration and ankle arthritis would also be interrelated, given their interconnected role in lower extremity force transmission. Surprisingly, the literature correlating lumbar degeneration and lower extremity osteoarthritis has overlooked this association and has focused solely on the hip and knee. To our knowledge, this study is the first to identify a statistically significant association between tibiotalar joint osteoarthritis and lumbar disc degeneration.

The literature supported analysis of our data. Miller and colleagues²⁸ evaluated disc degeneration in 600 autopsy specimens using the Nachemson²⁹ grading system. This system categorizes disc degeneration into 4 grades based on macroscopic appearance. Miller and colleagues²⁸ reported evidence of degenerative changes as early as the second decade of life, primarily involving the L3–L4 and L4–L5 levels. Of note, the Nachemson²⁹ classification system includes only evidence of marginal osteophytes in grade 4 disease, which was not identified by Miller and colleagues²⁸ until the fourth decade. These results were similar to those in our study, in which the L3-L4 and L4-L5 intervertebral levels were most commonly affected. However, in our study, significant degenerative changes were found in the third decade of life. 

In addition, the percentage of specimens with severe disc degeneration increased with each decade (Figure 8). A substantial amount of histologic evidence demonstrates the progression of disc degeneration with age. With increased age, there is a gradual decrease in the osmotic swelling of intervertebral discs³⁰ and a 2-fold decrease in disc hydration between adolescence and the eighth decade.³¹ Furthermore, the nucleus pulposus undergoes progressive fibrosis,^32,33 with a 5-fold decrease in the fixed-charge density of nucleus glycosaminoglycans,³⁴ and a 2-fold increase in intervertebral disc creep while under compression after age 30 years.³⁵

While analyzing our findings, we had difficulty in determining which pathologic condition debuts and, subsequently, affects the other. According to our results, the mean grade of tibiotalar joint arthritis was higher than that of DDD in specimens through the third and fourth decades of life (Figure 7). After the age of 50 years, the mean grade of DDD surpasses that of tibiotalar arthritis. This may be initially interpreted that development of tibiotalar joint arthritis precedes lumbar disc degeneration. Ankle osteoarthritis is relatively rare, and given that the vast majority of ankle osteoarthritis is secondary to trauma,²² we would expect to see a higher incidence of ankle osteoarthritis in a younger, more active cohort. In addition, given our finding that ankle arthritis is related to lumbar disc degeneration, one could speculate that tibiotalar arthritis at a young age predisposes an individual to developing lumbar degeneration later in life.

However, this conclusion is inherently flawed; closer examination of the data revealed that the mean grade of tibiotalar arthritis and DDD in the third and fourth decades is relatively low, between grade 0 and grade 1 (Figure 7). Therefore, it is difficult to arrive at a conclusion when comparing such small values. Second, we must remember that we are comparing an average value of disc degeneration across all lumbar levels. When a specimen has only 1 disc that is severely degenerated, this value is averaged across all 5 lumbar levels and, thus, the overall mean grade of arthrosis is significantly diminished.

In fact, data from previous studies concur with the second argument. Upper-level lumbar disc degeneration is relatively rare and the vast majority of patients with disc degeneration present with significant disease in only 1 or 2 discs.^36,37 Analysis of the specimens in this study revealed bony evidence of disc degeneration present at all 5 lumbar levels in over half of the specimens examined (57%). However, the majority of specimens in this cohort exhibit only low-grade degeneration. When specimens were analyzed for severe arthrosis (grade 3 and higher), nearly half of the specimens were found to have severe disease involving only 1 intervertebral disc (Figure 6). Data from Miller and colleagues²⁸ and the present study show that the upper lumbar levels were relatively spared; the L3-L4 and L4-L5 lumbar levels showed the highest prevalence and severity of degenerative change.

To address this issue, we evaluated the percentage of specimens per decade with severe arthrosis (grade 3 and higher) of at least 1 lumbar intervertebral disc and 1 tibiotalar joint. Severe lumbar disc degeneration was found to be more prevalent than severe ankle arthritis in individuals age 20 years or older (Figure 8). Therefore, we postulate that significant degenerative changes in the lumbar spine precede the development of severe ankle arthritis.

One can further speculate that sequelae from lumbar disc degeneration may lead to the development of tibiotalar arthritis, given our finding that severe lumbar degeneration predisposes an individual to the development of ankle arthritis. Because significant lumbar disc degeneration has long been known to result in both spinal nerve and cord compression, we hypothesize that this resultant neurocompression promotes altered gait and translation of atypical forces to the ankle and foot, thus predisposing to the onset and/or progression of osteoarthritis. In support of this hypothesis, Morag and colleagues¹⁵ demonstrated that neurologic compression produced an altered posture and gait because of lost motor function and afferent proprioceptive sensation. This form of neurologic compromise may exert atypical forces upon the foot and ankle, predisposing the joint to accelerated wear and primary arthrosis.

In addition, DDD involving 3 or more lumbar intervertebral levels was found to significantly increase the likelihood of the subject having severe tibiotalar joint arthritis. Provided that lumbar disc degeneration typically involves significant degeneration at 1 level, we assume that significant arthrosis at 3 or more levels correlates to an overall more severe DDD with a higher corresponding likelihood of neural compression. However, compression of peripheral lower extremity nerves has been shown to result in neuropathic arthropathy akin to the diabetic Charcot foot.³⁸ This could be a possible mechanism of accelerated ankle arthritis, but this study did not examine soft-tissue disease nor take into account other medical comorbidities of each specimen, including genetic predispositions towards osteoarthritis.

It should be noted that the aforementioned causative relationship between lumbar disc degeneration and tibiotalar arthritis is speculative and cannot be demonstrated definitively by this investigation. We acknowledge limitations of this study and the need for further research of the possible causative mechanism(s) of accelerated ankle arthrosis secondary to lumbar spinal disease. Ideally, the questions posed by our report would be answered via a large prospective cohort study that utilized both serial imaging and autopsy analysis. Unfortunately, this form of study is logistically and financially difficult to perform.

This was a retrospective cadaveric study in which determination of arthrosis severity was based solely on bony evidence. Therefore, the role of soft-tissue disease in the pathogenesis of arthrosis of the lumbar spine and tibiotalar joint could not be assessed, nor could definitive associations to clinically symptomatic disease. We made the assumption that progression of bone degeneration in both the lumbar spine and tibiotalar joint corresponded equally to the associated soft-tissue changes. Given this assumption, we cannot definitively conclude that degeneration of the lumbar spine precedes that of the ankle, because the absence of magnetic resonance imaging or fresh autopsy specimens in our study misses the early degenerative changes in the discs that precede the bony alteration measured in our study. Furthermore, readers should note that since this study compared only bone morphology, no emphasis was placed on clinical manifestation of lumbar disc degeneration or tibiotalar joint arthritis. As mentioned earlier, radiologic evidence of disc degeneration was found in 90% of adults age 50 to 59 years, according to a study by Hult⁵; however, it is important to note that not all individuals studied were symptomatic clinically. Unfortunately, medical records were not available for the bony specimens, and clinical correlations could not be assessed during this investigation.

Furthermore, no special attention was given to other pathologic conditions observed during specimen measurement. The presence of diseases, such as osteoporosis, spondylolysis, or previous traumatic injury, may have had implications in the resultant joint degeneration. Finally, the evaluation of arthrosis was performed subjectively without measuring reliability. However, the present analysis includes a large sample, each joint type was reviewed by a single examiner, and used a classification system that was modeled on a validated grading system. Ideally, multiple individuals should have been used for each type of measurement, with subsequent analysis of intraobserver and interobserver reliability.

Conclusion

Based on our study of a large population of adult skeletal specimens, we ascertained that lumbar intervertebral disc degeneration and tibiotalar osteoarthritis are associated. The prevalence of severe lumbar disc degeneration was higher than that of tibiotalar joint arthritis in individuals age 20 years or older. This may suggest that gait changes from disc degeneration or neural compression in the lumbar spine may play a role in the development of ankle osteoarthritis. Additionally, subjects with severe disc degeneration were twice as likely to develop significant tibiotalar osteoarthritis. This must be considered in the differential when treating patients with degenerative changes of the lumbar spine and leg pain.

Subcutaneous rupture of the tibialis anterior (TA) tendon has been reported predominantly in case reports and small case series because of the relative rarity of the injury. Unlike traumatic lacerations or open injuries to the tendon, subcutaneous injuries often go unnoticed by patients because of compensation by surrounding dorsiflexors of the foot and toes—namely, the extensor hallucis longus (EHL) and the extensor digitorum longus (EDL).¹ This can delay presentation to an orthopedic surgeon and lead to difficulties in treatment, such as allograft or autograft being required if primary repair is no longer possible. Case reports and series have described treatment methods as well as anecdotal evidence of outcomes after operative repair or conservative treatment, but there have been no comprehensive systematic reviews of outcomes after various types of treatment. Authors have come to conclusions about expected outcomes based on patient age, time to treatment, treatment used, and other variables, but no reviews have examined these variables across multiple studies. Given the low level of the evidence presented in most of these reports, it is difficult to perform a meta-analysis of the data.

Instead, we systematically reviewed 87 cases from all pertinent studies and examined commonly reported data, such as patient age, time to treatment, treatment used, and outcome. Using the PICO (population, intervention, comparison, outcome) model for systematic reviews, we looked at patients who had closed, spontaneous, complete rupture of the TA tendon and underwent operative repair or conservative treatment of the injury. Outcomes surveyed included successful operative repair or conservative treatment, as measured by objective systems, such as MMSS (Manual Muscle Strength Scale) score, AOFAS (American Orthopaedic Foot and Ankle Society) hindfoot score, and FAOS (Foot and Ankle Outcome Score) testing, or by subjective description of posttreatment outcome.

We intend this review to serve as a guide for surgeons who find themselves treating a ruptured TA tendon, a relatively rare injury. They will be able to select the operative technique or conservative treatment that best matches the patient’s needs, based on comparison with previous case studies.

Materials and Methods

The cases reviewed for this study were found through a comprehensive PubMed search and an independent review of references cited in similar articles. Articles included were published between 1975 and 2012, inclusive. The latest search was performed on March 22, 2013. The search criteria were tibialis anterior [Title/Abstract] OR anterior tibial [Title/Abstract] AND rupture [Title/Abstract]) AND surgery. Only English-language articles, or articles already translated into English, were included. Eligible studies described cases of closed tendon rupture. No traumatic lacerations or open ruptures were included. If a study described both open and subcutaneous ruptures, only the subcutaneous cases were included. Further, partial ruptures were not included. In addition, ruptures caused directly by a known comorbid condition—for example, a rupture caused by a gouty tophaceous deposit at the site of rupture²—were not included. Data were extracted from publications independently and analyzed in a Microsoft Excel workbook (Microsoft, Redmond, Washington). Variables examined included patient age and sex, side involved, time to treatment, mechanism of injury, defect size, predisposing comorbidities, surgery or conservative treatment, type of operative repair (if applicable), graft used (if applicable), pretreatment function (by independent scoring system, if applicable), and posttreatment function. These variables were not necessarily reported in all the studies.

A potential bias exists in our PubMed search. As the query was specific for studies that included operative repair of a ruptured TA tendon, case studies that involved only conservative treatment were excluded. However, the primary goal of this review was to compare operative possibilities and the patient characteristics and outcomes associated with these surgeries.

Results

Figure 1 shows the criteria used to select eligible papers for review. Twenty-three papers matched the criteria.^3-25 Data were independently extracted from these papers, as described in the Methods section. Again, not all variables were reported by all authors. Sammarco and colleagues²¹ reported time to treatment as a mean for 2 groups: 8 cases defined as “early” treatment (mean time to treatment, 0.625 months) and 11 defined as “late” treatment (mean time to treatment, 10.7 months). These mean times were therefore used independently for each case in calculating mean time to treatment for this systematic review.

Table 1 lists the demographics. There were 40 male and 25 female patients, and 22 cases in which sex was not specified. Mean age was 63.9 years (surgery group), 72.4 years (conservative treatment group), and 65.8 years (overall). Of the 87 patients, 72 underwent surgery, and 15 were treated with conservative measures.

Table 2 lists the operative techniques identified. Of the 72 surgeries, 23 were primary repairs, 12 were primary repairs of the anatomical insertion, and 18 involved use of autograft.

Time to treatment was available for 54 of the 87 cases (Table 3). Primary repair was most often performed in cases in which the injury was less than 3 months old, and autograft was most often used in cases in which the injury occurred more than 3 months before presentation.

Posttreatment outcome scores were available for 59 cases. Only 3 authors reported preoperative scores.^5,21,24 None of the authors who used conservative treatment measures reported pretreatment scores. Scores used included the MMSS score (26 cases), the AOFAS hindfoot score (16 cases),²⁶ the FAOS (17 cases),²⁷ and the Tinetti gait and balance score (3 cases; the author also used the MMSS score).²⁸Table 4 lists the mean posttreatment scores for patients who underwent surgery and patients treated conservatively. AOFAS, MMSS, and Tinetti scores and FAOS were used by authors presenting operative treatment outcomes. Only posttreatment FAOS was available for both surgery (84.4/100) and conservative treatment (69.4/100).

Discussion

Closed rupture of the TA tendon is a relatively rare entity occurring mostly in older patients without any history of acute, traumatic injury. Some patients, however, recall a particular moment of rupture, often accompanied immediately by pain and swelling, which eventually resolve. Later sequelae include footdrop with associated steppage gait and a palpable mass on the dorsal aspect of the ankle.^3,21 Chronic TA tendon rupture can also lead to clawing of the toes as the other foot extensors (EHL, EDL) overcompensate. Cohen and Gordon¹ described the case of a patient who ruptured a TA tendon 25 years earlier and then, in the absence of operative repair, developed hypertrophy of the EHL and the EDL. This extensor substitution led to hammer toes and plantar prominence of the metatarsal heads, ultimately leading to moderate pain and a neuroma. Although this particular outcome is likely rare, the more common sequelae of footdrop, flatfoot, Achilles tendon contracture, and compromised gait are reason enough to consider operative repair for any ruptured TA tendon.

Most previous studies of TA tendon rupture were case reports and case studies. In the largest series, Sammarco and colleagues²¹ described 19 cases of closed rupture. These included 3 traumatic cases, 1 by blunt trauma to the tendon and 2 of open laceration, all treated surgically with various methods. Unfortunately, these 3 traumatic cases were not separated in the authors’ analysis and therefore had to be included in this systematic review. Including them here did not compromise our goals in this review, which included examining typical patient demographics and the most common methods of operative repair.

Conservative measures remain a treatment possibility for some patients. We found that patients treated with conservative measures historically have been older (mean age, 72.4 years) than patients treated surgically (mean age, 63.9 years). However, advanced age itself is not a contraindication for operative repair of a TA tendon rupture, and authors have described positive outcomes for active, elderly (>70 years) patients who wanted to maintain their activity level and therefore opted for operative repair.^{7,8,10,13,16,24} Ouzounian and Anderson¹⁸ described functional limitations (eg, persistent footdrop, slapfoot gait, limitations in walking) after conservative treatment with an ankle-foot orthosis. Operative repair offers the chance for better functional outcome for patients who are surgical candidates and lead even a mildly active lifestyle.

Of operative repair methods, primary repair is used most often. This technique, however, must be allowed by the gap between the 2 ruptured ends after débridement of any necrotic tissue. If the distal stump is not viable, primary repair of the proximal stump to the native anatomical insertion is feasible. Figure 2, reprinted from a case report by Rajagopalan and colleagues,¹⁹ shows a ligament–osseous reattachment of the proximal stump using suture anchors to the medial cuneiform. Both primary repair and repair to the anatomical insertion can be augmented with Achilles tendon lengthening if needed to achieve balance between flexor and extensor functions of the ankle.

If the gap between the 2 stumps cannot be covered by the native tendon, then autograft, another surgical technique with positive outcomes, can be used. The most popular autograft sites historically have been the EDL, Achilles, and plantaris tendons. In addition, Goehring and Liakos⁹ described 3 cases of good results with semitendinosus autograft. Sapkas and colleagues²² used a free-sliding TA graft harvested from the healthy tissue of the proximal tendon stump. Their technique is depicted in Figure 3. Sliding tendon lengthening, well described by Trout and colleagues²⁴ in a case study, is feasible for use of the native tendon when there is a gap to bridge between the 2 stumps of ruptured tendon. EHL or EDL transfer with or without Achilles lengthening is another option, albeit historically less often used.^6,7 This technique is depicted in Figure 4, reprinted from a case series by Ellington and colleagues,⁷ who used EHL transfer with and without Achilles tendon lengthening in 9 cases.

Last, less popular techniques have included repair to sites other than the medial cuneiform, including the neck of the talus and the navicular bone.^10,13 An Achilles tendon allograft was used in a case described by Aderinto and Gross³ to repair a ruptured tendon found incidentally on preoperative examination for a scheduled knee arthroplasty. The patient had a postoperative MMSS score of 4/5.

Overall, primary repair is clearly preferred, but successful outcomes can be achieved by other means. As Table 3 shows, primary repair is more often used for ruptures less than 3 months old, and autograft for older ruptures. Although which operative technique to use can be decided after necrotic tissue is débrided, surgeons should try to ascertain age of injury ahead of time so that, going into surgery, they will have a better idea of the feasibility of primary repair.

Posttreatment ankle scores were not widely available. As Table 4 indicates, only FAOS was used for the conservative treatment cases. However, raw mean FAOS and raw mean AOFAS hindfoot, MMSS, and Tinetti scores showed that good outcomes and high scores can be achieved with surgery. Further, the mean FAOS reported by Gwynne-Jones and colleagues¹⁰ and Markarian and colleagues¹³ showed a clinically significant difference between surgery and conservative treatment. DiDomenico and colleagues,⁵ Sammarco and colleagues,²¹ and Trout and colleagues²⁴ were the only authors who reported pretreatment and posttreatment scores.

We intend this systematic review of the literature on closed TA rupture to serve as a guide for surgeons who find themselves treating this relatively rare injury, which often presents with only a chief complaint of the foot catching while walking. Overall, the literature shows that operative repair provides very good outcomes for many patients. Patients who are surgical candidates and amenable to surgery can be counseled that operative repair leads to fewer sequelae, such as persistent footdrop and flatfooted gait, with a strong likelihood of return to baseline activity status. Patients who are not surgical candidates or are strongly against surgery can be offered conservative treatment with an ankle-foot orthosis or physical therapy, but they should also be counseled that persistent gait abnormalities and weakness in dorsiflexion are likely outcomes. Surgeons must also consider age of injury (time from probable rupture to presentation), estimating a particular moment of rupture if unknown by the patient. They can then gauge the feasibility of primary repair and, during surgery, decide which technique (primary repair, tendon transfer, autograft, or other technique) will produce the best results. They can also use scores such as the FAOS and the AOFAS hindfoot, MMSS, and Tinetti scores to compare preoperative and postoperative function, though subjective reports of return to previous activity can also serve as markers of successful repair.

This review highlights the need for further study regarding the treatment of TA ruptures. Larger, randomized studies with validated scoring systems for preoperative and postoperative function would offer more insight onto the best treatment options for these complex injuries.

Subcutaneous rupture of the tibialis anterior (TA) tendon has been reported predominantly in case reports and small case series because of the relative rarity of the injury. Unlike traumatic lacerations or open injuries to the tendon, subcutaneous injuries often go unnoticed by patients because of compensation by surrounding dorsiflexors of the foot and toes—namely, the extensor hallucis longus (EHL) and the extensor digitorum longus (EDL).¹ This can delay presentation to an orthopedic surgeon and lead to difficulties in treatment, such as allograft or autograft being required if primary repair is no longer possible. Case reports and series have described treatment methods as well as anecdotal evidence of outcomes after operative repair or conservative treatment, but there have been no comprehensive systematic reviews of outcomes after various types of treatment. Authors have come to conclusions about expected outcomes based on patient age, time to treatment, treatment used, and other variables, but no reviews have examined these variables across multiple studies. Given the low level of the evidence presented in most of these reports, it is difficult to perform a meta-analysis of the data.

Instead, we systematically reviewed 87 cases from all pertinent studies and examined commonly reported data, such as patient age, time to treatment, treatment used, and outcome. Using the PICO (population, intervention, comparison, outcome) model for systematic reviews, we looked at patients who had closed, spontaneous, complete rupture of the TA tendon and underwent operative repair or conservative treatment of the injury. Outcomes surveyed included successful operative repair or conservative treatment, as measured by objective systems, such as MMSS (Manual Muscle Strength Scale) score, AOFAS (American Orthopaedic Foot and Ankle Society) hindfoot score, and FAOS (Foot and Ankle Outcome Score) testing, or by subjective description of posttreatment outcome.

We intend this review to serve as a guide for surgeons who find themselves treating a ruptured TA tendon, a relatively rare injury. They will be able to select the operative technique or conservative treatment that best matches the patient’s needs, based on comparison with previous case studies.

Materials and Methods

The cases reviewed for this study were found through a comprehensive PubMed search and an independent review of references cited in similar articles. Articles included were published between 1975 and 2012, inclusive. The latest search was performed on March 22, 2013. The search criteria were tibialis anterior [Title/Abstract] OR anterior tibial [Title/Abstract] AND rupture [Title/Abstract]) AND surgery. Only English-language articles, or articles already translated into English, were included. Eligible studies described cases of closed tendon rupture. No traumatic lacerations or open ruptures were included. If a study described both open and subcutaneous ruptures, only the subcutaneous cases were included. Further, partial ruptures were not included. In addition, ruptures caused directly by a known comorbid condition—for example, a rupture caused by a gouty tophaceous deposit at the site of rupture²—were not included. Data were extracted from publications independently and analyzed in a Microsoft Excel workbook (Microsoft, Redmond, Washington). Variables examined included patient age and sex, side involved, time to treatment, mechanism of injury, defect size, predisposing comorbidities, surgery or conservative treatment, type of operative repair (if applicable), graft used (if applicable), pretreatment function (by independent scoring system, if applicable), and posttreatment function. These variables were not necessarily reported in all the studies.

A potential bias exists in our PubMed search. As the query was specific for studies that included operative repair of a ruptured TA tendon, case studies that involved only conservative treatment were excluded. However, the primary goal of this review was to compare operative possibilities and the patient characteristics and outcomes associated with these surgeries.

Results

Figure 1 shows the criteria used to select eligible papers for review. Twenty-three papers matched the criteria.^3-25 Data were independently extracted from these papers, as described in the Methods section. Again, not all variables were reported by all authors. Sammarco and colleagues²¹ reported time to treatment as a mean for 2 groups: 8 cases defined as “early” treatment (mean time to treatment, 0.625 months) and 11 defined as “late” treatment (mean time to treatment, 10.7 months). These mean times were therefore used independently for each case in calculating mean time to treatment for this systematic review.

Table 1 lists the demographics. There were 40 male and 25 female patients, and 22 cases in which sex was not specified. Mean age was 63.9 years (surgery group), 72.4 years (conservative treatment group), and 65.8 years (overall). Of the 87 patients, 72 underwent surgery, and 15 were treated with conservative measures.

Table 2 lists the operative techniques identified. Of the 72 surgeries, 23 were primary repairs, 12 were primary repairs of the anatomical insertion, and 18 involved use of autograft.

Time to treatment was available for 54 of the 87 cases (Table 3). Primary repair was most often performed in cases in which the injury was less than 3 months old, and autograft was most often used in cases in which the injury occurred more than 3 months before presentation.

Posttreatment outcome scores were available for 59 cases. Only 3 authors reported preoperative scores.^5,21,24 None of the authors who used conservative treatment measures reported pretreatment scores. Scores used included the MMSS score (26 cases), the AOFAS hindfoot score (16 cases),²⁶ the FAOS (17 cases),²⁷ and the Tinetti gait and balance score (3 cases; the author also used the MMSS score).²⁸Table 4 lists the mean posttreatment scores for patients who underwent surgery and patients treated conservatively. AOFAS, MMSS, and Tinetti scores and FAOS were used by authors presenting operative treatment outcomes. Only posttreatment FAOS was available for both surgery (84.4/100) and conservative treatment (69.4/100).

Discussion

Closed rupture of the TA tendon is a relatively rare entity occurring mostly in older patients without any history of acute, traumatic injury. Some patients, however, recall a particular moment of rupture, often accompanied immediately by pain and swelling, which eventually resolve. Later sequelae include footdrop with associated steppage gait and a palpable mass on the dorsal aspect of the ankle.^3,21 Chronic TA tendon rupture can also lead to clawing of the toes as the other foot extensors (EHL, EDL) overcompensate. Cohen and Gordon¹ described the case of a patient who ruptured a TA tendon 25 years earlier and then, in the absence of operative repair, developed hypertrophy of the EHL and the EDL. This extensor substitution led to hammer toes and plantar prominence of the metatarsal heads, ultimately leading to moderate pain and a neuroma. Although this particular outcome is likely rare, the more common sequelae of footdrop, flatfoot, Achilles tendon contracture, and compromised gait are reason enough to consider operative repair for any ruptured TA tendon.

Most previous studies of TA tendon rupture were case reports and case studies. In the largest series, Sammarco and colleagues²¹ described 19 cases of closed rupture. These included 3 traumatic cases, 1 by blunt trauma to the tendon and 2 of open laceration, all treated surgically with various methods. Unfortunately, these 3 traumatic cases were not separated in the authors’ analysis and therefore had to be included in this systematic review. Including them here did not compromise our goals in this review, which included examining typical patient demographics and the most common methods of operative repair.

Conservative measures remain a treatment possibility for some patients. We found that patients treated with conservative measures historically have been older (mean age, 72.4 years) than patients treated surgically (mean age, 63.9 years). However, advanced age itself is not a contraindication for operative repair of a TA tendon rupture, and authors have described positive outcomes for active, elderly (>70 years) patients who wanted to maintain their activity level and therefore opted for operative repair.^{7,8,10,13,16,24} Ouzounian and Anderson¹⁸ described functional limitations (eg, persistent footdrop, slapfoot gait, limitations in walking) after conservative treatment with an ankle-foot orthosis. Operative repair offers the chance for better functional outcome for patients who are surgical candidates and lead even a mildly active lifestyle.

Of operative repair methods, primary repair is used most often. This technique, however, must be allowed by the gap between the 2 ruptured ends after débridement of any necrotic tissue. If the distal stump is not viable, primary repair of the proximal stump to the native anatomical insertion is feasible. Figure 2, reprinted from a case report by Rajagopalan and colleagues,¹⁹ shows a ligament–osseous reattachment of the proximal stump using suture anchors to the medial cuneiform. Both primary repair and repair to the anatomical insertion can be augmented with Achilles tendon lengthening if needed to achieve balance between flexor and extensor functions of the ankle.

If the gap between the 2 stumps cannot be covered by the native tendon, then autograft, another surgical technique with positive outcomes, can be used. The most popular autograft sites historically have been the EDL, Achilles, and plantaris tendons. In addition, Goehring and Liakos⁹ described 3 cases of good results with semitendinosus autograft. Sapkas and colleagues²² used a free-sliding TA graft harvested from the healthy tissue of the proximal tendon stump. Their technique is depicted in Figure 3. Sliding tendon lengthening, well described by Trout and colleagues²⁴ in a case study, is feasible for use of the native tendon when there is a gap to bridge between the 2 stumps of ruptured tendon. EHL or EDL transfer with or without Achilles lengthening is another option, albeit historically less often used.^6,7 This technique is depicted in Figure 4, reprinted from a case series by Ellington and colleagues,⁷ who used EHL transfer with and without Achilles tendon lengthening in 9 cases.

Last, less popular techniques have included repair to sites other than the medial cuneiform, including the neck of the talus and the navicular bone.^10,13 An Achilles tendon allograft was used in a case described by Aderinto and Gross³ to repair a ruptured tendon found incidentally on preoperative examination for a scheduled knee arthroplasty. The patient had a postoperative MMSS score of 4/5.

Overall, primary repair is clearly preferred, but successful outcomes can be achieved by other means. As Table 3 shows, primary repair is more often used for ruptures less than 3 months old, and autograft for older ruptures. Although which operative technique to use can be decided after necrotic tissue is débrided, surgeons should try to ascertain age of injury ahead of time so that, going into surgery, they will have a better idea of the feasibility of primary repair.

Posttreatment ankle scores were not widely available. As Table 4 indicates, only FAOS was used for the conservative treatment cases. However, raw mean FAOS and raw mean AOFAS hindfoot, MMSS, and Tinetti scores showed that good outcomes and high scores can be achieved with surgery. Further, the mean FAOS reported by Gwynne-Jones and colleagues¹⁰ and Markarian and colleagues¹³ showed a clinically significant difference between surgery and conservative treatment. DiDomenico and colleagues,⁵ Sammarco and colleagues,²¹ and Trout and colleagues²⁴ were the only authors who reported pretreatment and posttreatment scores.

We intend this systematic review of the literature on closed TA rupture to serve as a guide for surgeons who find themselves treating this relatively rare injury, which often presents with only a chief complaint of the foot catching while walking. Overall, the literature shows that operative repair provides very good outcomes for many patients. Patients who are surgical candidates and amenable to surgery can be counseled that operative repair leads to fewer sequelae, such as persistent footdrop and flatfooted gait, with a strong likelihood of return to baseline activity status. Patients who are not surgical candidates or are strongly against surgery can be offered conservative treatment with an ankle-foot orthosis or physical therapy, but they should also be counseled that persistent gait abnormalities and weakness in dorsiflexion are likely outcomes. Surgeons must also consider age of injury (time from probable rupture to presentation), estimating a particular moment of rupture if unknown by the patient. They can then gauge the feasibility of primary repair and, during surgery, decide which technique (primary repair, tendon transfer, autograft, or other technique) will produce the best results. They can also use scores such as the FAOS and the AOFAS hindfoot, MMSS, and Tinetti scores to compare preoperative and postoperative function, though subjective reports of return to previous activity can also serve as markers of successful repair.

This review highlights the need for further study regarding the treatment of TA ruptures. Larger, randomized studies with validated scoring systems for preoperative and postoperative function would offer more insight onto the best treatment options for these complex injuries.

Subcutaneous rupture of the tibialis anterior (TA) tendon has been reported predominantly in case reports and small case series because of the relative rarity of the injury. Unlike traumatic lacerations or open injuries to the tendon, subcutaneous injuries often go unnoticed by patients because of compensation by surrounding dorsiflexors of the foot and toes—namely, the extensor hallucis longus (EHL) and the extensor digitorum longus (EDL).¹ This can delay presentation to an orthopedic surgeon and lead to difficulties in treatment, such as allograft or autograft being required if primary repair is no longer possible. Case reports and series have described treatment methods as well as anecdotal evidence of outcomes after operative repair or conservative treatment, but there have been no comprehensive systematic reviews of outcomes after various types of treatment. Authors have come to conclusions about expected outcomes based on patient age, time to treatment, treatment used, and other variables, but no reviews have examined these variables across multiple studies. Given the low level of the evidence presented in most of these reports, it is difficult to perform a meta-analysis of the data.

Instead, we systematically reviewed 87 cases from all pertinent studies and examined commonly reported data, such as patient age, time to treatment, treatment used, and outcome. Using the PICO (population, intervention, comparison, outcome) model for systematic reviews, we looked at patients who had closed, spontaneous, complete rupture of the TA tendon and underwent operative repair or conservative treatment of the injury. Outcomes surveyed included successful operative repair or conservative treatment, as measured by objective systems, such as MMSS (Manual Muscle Strength Scale) score, AOFAS (American Orthopaedic Foot and Ankle Society) hindfoot score, and FAOS (Foot and Ankle Outcome Score) testing, or by subjective description of posttreatment outcome.

We intend this review to serve as a guide for surgeons who find themselves treating a ruptured TA tendon, a relatively rare injury. They will be able to select the operative technique or conservative treatment that best matches the patient’s needs, based on comparison with previous case studies.

Materials and Methods

The cases reviewed for this study were found through a comprehensive PubMed search and an independent review of references cited in similar articles. Articles included were published between 1975 and 2012, inclusive. The latest search was performed on March 22, 2013. The search criteria were tibialis anterior [Title/Abstract] OR anterior tibial [Title/Abstract] AND rupture [Title/Abstract]) AND surgery. Only English-language articles, or articles already translated into English, were included. Eligible studies described cases of closed tendon rupture. No traumatic lacerations or open ruptures were included. If a study described both open and subcutaneous ruptures, only the subcutaneous cases were included. Further, partial ruptures were not included. In addition, ruptures caused directly by a known comorbid condition—for example, a rupture caused by a gouty tophaceous deposit at the site of rupture²—were not included. Data were extracted from publications independently and analyzed in a Microsoft Excel workbook (Microsoft, Redmond, Washington). Variables examined included patient age and sex, side involved, time to treatment, mechanism of injury, defect size, predisposing comorbidities, surgery or conservative treatment, type of operative repair (if applicable), graft used (if applicable), pretreatment function (by independent scoring system, if applicable), and posttreatment function. These variables were not necessarily reported in all the studies.

A potential bias exists in our PubMed search. As the query was specific for studies that included operative repair of a ruptured TA tendon, case studies that involved only conservative treatment were excluded. However, the primary goal of this review was to compare operative possibilities and the patient characteristics and outcomes associated with these surgeries.

Results

Figure 1 shows the criteria used to select eligible papers for review. Twenty-three papers matched the criteria.^3-25 Data were independently extracted from these papers, as described in the Methods section. Again, not all variables were reported by all authors. Sammarco and colleagues²¹ reported time to treatment as a mean for 2 groups: 8 cases defined as “early” treatment (mean time to treatment, 0.625 months) and 11 defined as “late” treatment (mean time to treatment, 10.7 months). These mean times were therefore used independently for each case in calculating mean time to treatment for this systematic review.

Table 1 lists the demographics. There were 40 male and 25 female patients, and 22 cases in which sex was not specified. Mean age was 63.9 years (surgery group), 72.4 years (conservative treatment group), and 65.8 years (overall). Of the 87 patients, 72 underwent surgery, and 15 were treated with conservative measures.

Table 2 lists the operative techniques identified. Of the 72 surgeries, 23 were primary repairs, 12 were primary repairs of the anatomical insertion, and 18 involved use of autograft.

Time to treatment was available for 54 of the 87 cases (Table 3). Primary repair was most often performed in cases in which the injury was less than 3 months old, and autograft was most often used in cases in which the injury occurred more than 3 months before presentation.

Posttreatment outcome scores were available for 59 cases. Only 3 authors reported preoperative scores.^5,21,24 None of the authors who used conservative treatment measures reported pretreatment scores. Scores used included the MMSS score (26 cases), the AOFAS hindfoot score (16 cases),²⁶ the FAOS (17 cases),²⁷ and the Tinetti gait and balance score (3 cases; the author also used the MMSS score).²⁸Table 4 lists the mean posttreatment scores for patients who underwent surgery and patients treated conservatively. AOFAS, MMSS, and Tinetti scores and FAOS were used by authors presenting operative treatment outcomes. Only posttreatment FAOS was available for both surgery (84.4/100) and conservative treatment (69.4/100).

Discussion

Closed rupture of the TA tendon is a relatively rare entity occurring mostly in older patients without any history of acute, traumatic injury. Some patients, however, recall a particular moment of rupture, often accompanied immediately by pain and swelling, which eventually resolve. Later sequelae include footdrop with associated steppage gait and a palpable mass on the dorsal aspect of the ankle.^3,21 Chronic TA tendon rupture can also lead to clawing of the toes as the other foot extensors (EHL, EDL) overcompensate. Cohen and Gordon¹ described the case of a patient who ruptured a TA tendon 25 years earlier and then, in the absence of operative repair, developed hypertrophy of the EHL and the EDL. This extensor substitution led to hammer toes and plantar prominence of the metatarsal heads, ultimately leading to moderate pain and a neuroma. Although this particular outcome is likely rare, the more common sequelae of footdrop, flatfoot, Achilles tendon contracture, and compromised gait are reason enough to consider operative repair for any ruptured TA tendon.

Most previous studies of TA tendon rupture were case reports and case studies. In the largest series, Sammarco and colleagues²¹ described 19 cases of closed rupture. These included 3 traumatic cases, 1 by blunt trauma to the tendon and 2 of open laceration, all treated surgically with various methods. Unfortunately, these 3 traumatic cases were not separated in the authors’ analysis and therefore had to be included in this systematic review. Including them here did not compromise our goals in this review, which included examining typical patient demographics and the most common methods of operative repair.

Conservative measures remain a treatment possibility for some patients. We found that patients treated with conservative measures historically have been older (mean age, 72.4 years) than patients treated surgically (mean age, 63.9 years). However, advanced age itself is not a contraindication for operative repair of a TA tendon rupture, and authors have described positive outcomes for active, elderly (>70 years) patients who wanted to maintain their activity level and therefore opted for operative repair.^{7,8,10,13,16,24} Ouzounian and Anderson¹⁸ described functional limitations (eg, persistent footdrop, slapfoot gait, limitations in walking) after conservative treatment with an ankle-foot orthosis. Operative repair offers the chance for better functional outcome for patients who are surgical candidates and lead even a mildly active lifestyle.

Of operative repair methods, primary repair is used most often. This technique, however, must be allowed by the gap between the 2 ruptured ends after débridement of any necrotic tissue. If the distal stump is not viable, primary repair of the proximal stump to the native anatomical insertion is feasible. Figure 2, reprinted from a case report by Rajagopalan and colleagues,¹⁹ shows a ligament–osseous reattachment of the proximal stump using suture anchors to the medial cuneiform. Both primary repair and repair to the anatomical insertion can be augmented with Achilles tendon lengthening if needed to achieve balance between flexor and extensor functions of the ankle.

If the gap between the 2 stumps cannot be covered by the native tendon, then autograft, another surgical technique with positive outcomes, can be used. The most popular autograft sites historically have been the EDL, Achilles, and plantaris tendons. In addition, Goehring and Liakos⁹ described 3 cases of good results with semitendinosus autograft. Sapkas and colleagues²² used a free-sliding TA graft harvested from the healthy tissue of the proximal tendon stump. Their technique is depicted in Figure 3. Sliding tendon lengthening, well described by Trout and colleagues²⁴ in a case study, is feasible for use of the native tendon when there is a gap to bridge between the 2 stumps of ruptured tendon. EHL or EDL transfer with or without Achilles lengthening is another option, albeit historically less often used.^6,7 This technique is depicted in Figure 4, reprinted from a case series by Ellington and colleagues,⁷ who used EHL transfer with and without Achilles tendon lengthening in 9 cases.

Last, less popular techniques have included repair to sites other than the medial cuneiform, including the neck of the talus and the navicular bone.^10,13 An Achilles tendon allograft was used in a case described by Aderinto and Gross³ to repair a ruptured tendon found incidentally on preoperative examination for a scheduled knee arthroplasty. The patient had a postoperative MMSS score of 4/5.

Overall, primary repair is clearly preferred, but successful outcomes can be achieved by other means. As Table 3 shows, primary repair is more often used for ruptures less than 3 months old, and autograft for older ruptures. Although which operative technique to use can be decided after necrotic tissue is débrided, surgeons should try to ascertain age of injury ahead of time so that, going into surgery, they will have a better idea of the feasibility of primary repair.

Posttreatment ankle scores were not widely available. As Table 4 indicates, only FAOS was used for the conservative treatment cases. However, raw mean FAOS and raw mean AOFAS hindfoot, MMSS, and Tinetti scores showed that good outcomes and high scores can be achieved with surgery. Further, the mean FAOS reported by Gwynne-Jones and colleagues¹⁰ and Markarian and colleagues¹³ showed a clinically significant difference between surgery and conservative treatment. DiDomenico and colleagues,⁵ Sammarco and colleagues,²¹ and Trout and colleagues²⁴ were the only authors who reported pretreatment and posttreatment scores.

We intend this systematic review of the literature on closed TA rupture to serve as a guide for surgeons who find themselves treating this relatively rare injury, which often presents with only a chief complaint of the foot catching while walking. Overall, the literature shows that operative repair provides very good outcomes for many patients. Patients who are surgical candidates and amenable to surgery can be counseled that operative repair leads to fewer sequelae, such as persistent footdrop and flatfooted gait, with a strong likelihood of return to baseline activity status. Patients who are not surgical candidates or are strongly against surgery can be offered conservative treatment with an ankle-foot orthosis or physical therapy, but they should also be counseled that persistent gait abnormalities and weakness in dorsiflexion are likely outcomes. Surgeons must also consider age of injury (time from probable rupture to presentation), estimating a particular moment of rupture if unknown by the patient. They can then gauge the feasibility of primary repair and, during surgery, decide which technique (primary repair, tendon transfer, autograft, or other technique) will produce the best results. They can also use scores such as the FAOS and the AOFAS hindfoot, MMSS, and Tinetti scores to compare preoperative and postoperative function, though subjective reports of return to previous activity can also serve as markers of successful repair.

This review highlights the need for further study regarding the treatment of TA ruptures. Larger, randomized studies with validated scoring systems for preoperative and postoperative function would offer more insight onto the best treatment options for these complex injuries.

Among nongeriatric atrial fibrillation patients without structural heart disease, those on dronedarone had a greater risk of atrial fibrillation, cardiovascular, and all-cause hospitalizations, compared with patients on amiodarone, sotalol, and class Ic drugs, a study published in Circulation showed. Amiodarone had the lowest risk of atrial fibrillation and cardiovascular hospitalizations, but not overall hospitalizations.

Nancy M. Allen LaPointe, Pharm. D., of the Duke University Medical Center, Durham, N.C., and her associates identified 8,562 atrial fibrillation patients on antiarrhythmic drugs (with a median age of 56 years) from the MarketScan database between 2006 and 2010, and found that the risk of hospitalization for atrial fibrillation was greater with dronedarone than class Ic drugs (hazard ratio, 1.59; 95% confidence interval, 1.13-2.24), amiodarone (HR, 2.63; 1.77-3.89), and sotalol (HR, 1.72; CI, 1.17-2.54), but was lower with amiodarone versus class Ic (HR, 0.68; CI, 0.57-0.80) drugs and sotalol (HR, 0.63; CI, 0.53-0.75).

“There are many potential reasons for these differences in hospitalization rates, including differences in side effects and efficacy of each drug in this patient population. … Additional studies are needed to confirm our findings and focus on potential explanations for differences in hospitalization rates for different AADs [antiarrhythmic drugs],” the investigators wrote.

Read the full article here: Circ. Cardiovasc. Qual. Outcomes 2015 (doi:10.1161/circoutcomes.114.001499).

Among nongeriatric atrial fibrillation patients without structural heart disease, those on dronedarone had a greater risk of atrial fibrillation, cardiovascular, and all-cause hospitalizations, compared with patients on amiodarone, sotalol, and class Ic drugs, a study published in Circulation showed. Amiodarone had the lowest risk of atrial fibrillation and cardiovascular hospitalizations, but not overall hospitalizations.

Nancy M. Allen LaPointe, Pharm. D., of the Duke University Medical Center, Durham, N.C., and her associates identified 8,562 atrial fibrillation patients on antiarrhythmic drugs (with a median age of 56 years) from the MarketScan database between 2006 and 2010, and found that the risk of hospitalization for atrial fibrillation was greater with dronedarone than class Ic drugs (hazard ratio, 1.59; 95% confidence interval, 1.13-2.24), amiodarone (HR, 2.63; 1.77-3.89), and sotalol (HR, 1.72; CI, 1.17-2.54), but was lower with amiodarone versus class Ic (HR, 0.68; CI, 0.57-0.80) drugs and sotalol (HR, 0.63; CI, 0.53-0.75).

“There are many potential reasons for these differences in hospitalization rates, including differences in side effects and efficacy of each drug in this patient population. … Additional studies are needed to confirm our findings and focus on potential explanations for differences in hospitalization rates for different AADs [antiarrhythmic drugs],” the investigators wrote.

Read the full article here: Circ. Cardiovasc. Qual. Outcomes 2015 (doi:10.1161/circoutcomes.114.001499).

Among nongeriatric atrial fibrillation patients without structural heart disease, those on dronedarone had a greater risk of atrial fibrillation, cardiovascular, and all-cause hospitalizations, compared with patients on amiodarone, sotalol, and class Ic drugs, a study published in Circulation showed. Amiodarone had the lowest risk of atrial fibrillation and cardiovascular hospitalizations, but not overall hospitalizations.

Nancy M. Allen LaPointe, Pharm. D., of the Duke University Medical Center, Durham, N.C., and her associates identified 8,562 atrial fibrillation patients on antiarrhythmic drugs (with a median age of 56 years) from the MarketScan database between 2006 and 2010, and found that the risk of hospitalization for atrial fibrillation was greater with dronedarone than class Ic drugs (hazard ratio, 1.59; 95% confidence interval, 1.13-2.24), amiodarone (HR, 2.63; 1.77-3.89), and sotalol (HR, 1.72; CI, 1.17-2.54), but was lower with amiodarone versus class Ic (HR, 0.68; CI, 0.57-0.80) drugs and sotalol (HR, 0.63; CI, 0.53-0.75).

“There are many potential reasons for these differences in hospitalization rates, including differences in side effects and efficacy of each drug in this patient population. … Additional studies are needed to confirm our findings and focus on potential explanations for differences in hospitalization rates for different AADs [antiarrhythmic drugs],” the investigators wrote.

Read the full article here: Circ. Cardiovasc. Qual. Outcomes 2015 (doi:10.1161/circoutcomes.114.001499).