Orthopedics

Scapular dislocation, which is also termed locked scapula or scapulothoracic dislocation, is an unusual condition that can be described as extrathoracic or intrathoracic dislocation, depending on the penetration of scapula into the thoracic cavity.

There have been 3 reported cases of intrathoracic scapular dislocations in the literature,^1-3all associated with a preexisting condition (eg, sternoclavicular separation, prior rib fracture, thoracotomy for a lung transplant procedure, or surgical resection of superior ribs during breast or pulmonary tumor excisions). Three published cases of intrathoracic scapular impaction involve comminuted scapular fractures with intrathoracic impaction of the inferior fragment through intercostal space.^4-6

Here we report an intrathoracic scapular dislocation that was not associated with fracture of the scapula or predisposing factors. To our knowledge, this is the first case of pure intrathoracic dislocation. The possibility of intrathoracic scapular dislocation should be considered as part of the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 29-year-old woman presented to the emergency department after a motor vehicle accident. She had tenderness over the left shoulder and left elbow with decreased range of motion; however, motor and sensory examination of the wrist and fingers were normal. No distal neurovascular deficit was noted.

Physical examination revealed pain on pelvic compression. We observed an asymmetrical appearance between shoulders; the left shoulder was superior when compared with the right side (Figure 1). Palpation of the scapula aggravated the pain. The inferior angle of the left scapula was not palpable, and the medial border was palpated through the intercostal space between the third and fourth ribs.

Initial radiographs showed additional left olecranon and bilateral ramus pubis fractures. A chest radiograph showed nondisplaced fractures of the second and third ribs without any obvious hemothorax or pneumothorax. No other pathology involving the chest, such as resection of the ribs or congenital anomaly, was observed. The patient reported no history of thoracic trauma or lung surgery. There were no fractures of the scapula, humerus, or clavicles. Thoracic computed tomography was performed, and 3-dimensional (3D) reconstruction showed that the inferior angle of scapula penetrated into the thoracic cavity through the third intercostal space (Figure 2).

Given the intrathoracic scapular dislocation diagnosis, closed reduction under sedation was planned. The patient was placed in the supine position, and reduction was performed by applying pressure on the shoulder anteriorly. This maneuver increased deformity. At the same time, another physician pulled the spine of the scapula superiorly, releasing the scapula out of the thoracic cavity. When the arm was slightly lowered to neutral position, scapular deformity was no longer present (Figure 3). A shoulder sling was applied, and the patient was hospitalized for surgical fixation of pelvic and olecranon fractures. The arm was immobilized in a sling for 1 week, and shoulder exercises were started immediately afterward.

At 1-month follow-up, full shoulder range of motion was achieved, although rehabilitation for the elbow continued. Final follow-up examination at 4 months revealed no difference between shoulders, and no recurrence occurred.

Discussion

Intrathoracic scapular dislocation is a rare injury. There are only a few cases reported in the literature, and most of them are well associated with a predisposing factor. Nettrour and colleagues¹ described the first intrathoracic scapular dislocation, which occurred 6 weeks after sternoclavicular separation and fracture of a rib. In the case reports of Ward and colleagues² and Fowler and colleagues,³ the predisposing factor was resection of the ribs due to pancoast tumor and breast carcinoma, respectively. The mechanism of these dislocations depends on a weak area over the thoracic cage, creating a fulcrum point for levering the scapula into the thoracic cavity.

There are other cases of scapular dislocations that are accompanied by a comminuted fracture of scapula; a review of the literature revealed 3 cases.^4-6 In our opinion, fracture of the inferior pole of the scapula leads to injury of the soft tissues and also results in intrathoracic impaction by creating a weak area over the thoracic cavity. This mechanism can be referred to as penetration.

Our case is singular because it is the first case that is not associated with fracture of the scapula or predisposing factors. Consequently, we report the first pure intrathoracic scapular dislocation in the literature. It is important to suspect intrathoracic scapular dislocation in the case of deformity (Figure 1), even in the absence of any predisposing factors or scapular fracture.

Although plain radiographs may not be elucidative, 3D reconstruction of computed tomography (Figure 2) reveals the pathology and plays an important role in guiding treatment.

In the treatment of our patient, relying on the unique dislocation mechanism without any fracture of the scapula or ribs, we started early active shoulder movement after 1 week of immobilization in a shoulder sling, which prevented recurrence of dislocation. In addition to presenting the first pure intrathoracic scapular dislocation, this case demonstrated satisfactory clinical results with short-term immobilization and early rehabilitation.

Conclusion

Contrary to the literature, the possibility of intrathoracic scapular dislocation should be considered in the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery, and when no fractures are detected. Shoulder or thorax computed tomography, especially 3D reconstructions, are helpful in diagnosing the condition and in guiding treatment. Closed reduction under sedation followed by early rehabilitation is an appropriate treatment method, which resulted in a full return of function in 1 month in our patient.

Scapular dislocation, which is also termed locked scapula or scapulothoracic dislocation, is an unusual condition that can be described as extrathoracic or intrathoracic dislocation, depending on the penetration of scapula into the thoracic cavity.

There have been 3 reported cases of intrathoracic scapular dislocations in the literature,^1-3all associated with a preexisting condition (eg, sternoclavicular separation, prior rib fracture, thoracotomy for a lung transplant procedure, or surgical resection of superior ribs during breast or pulmonary tumor excisions). Three published cases of intrathoracic scapular impaction involve comminuted scapular fractures with intrathoracic impaction of the inferior fragment through intercostal space.^4-6

Here we report an intrathoracic scapular dislocation that was not associated with fracture of the scapula or predisposing factors. To our knowledge, this is the first case of pure intrathoracic dislocation. The possibility of intrathoracic scapular dislocation should be considered as part of the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 29-year-old woman presented to the emergency department after a motor vehicle accident. She had tenderness over the left shoulder and left elbow with decreased range of motion; however, motor and sensory examination of the wrist and fingers were normal. No distal neurovascular deficit was noted.

Physical examination revealed pain on pelvic compression. We observed an asymmetrical appearance between shoulders; the left shoulder was superior when compared with the right side (Figure 1). Palpation of the scapula aggravated the pain. The inferior angle of the left scapula was not palpable, and the medial border was palpated through the intercostal space between the third and fourth ribs.

Initial radiographs showed additional left olecranon and bilateral ramus pubis fractures. A chest radiograph showed nondisplaced fractures of the second and third ribs without any obvious hemothorax or pneumothorax. No other pathology involving the chest, such as resection of the ribs or congenital anomaly, was observed. The patient reported no history of thoracic trauma or lung surgery. There were no fractures of the scapula, humerus, or clavicles. Thoracic computed tomography was performed, and 3-dimensional (3D) reconstruction showed that the inferior angle of scapula penetrated into the thoracic cavity through the third intercostal space (Figure 2).

Given the intrathoracic scapular dislocation diagnosis, closed reduction under sedation was planned. The patient was placed in the supine position, and reduction was performed by applying pressure on the shoulder anteriorly. This maneuver increased deformity. At the same time, another physician pulled the spine of the scapula superiorly, releasing the scapula out of the thoracic cavity. When the arm was slightly lowered to neutral position, scapular deformity was no longer present (Figure 3). A shoulder sling was applied, and the patient was hospitalized for surgical fixation of pelvic and olecranon fractures. The arm was immobilized in a sling for 1 week, and shoulder exercises were started immediately afterward.

At 1-month follow-up, full shoulder range of motion was achieved, although rehabilitation for the elbow continued. Final follow-up examination at 4 months revealed no difference between shoulders, and no recurrence occurred.

Discussion

Intrathoracic scapular dislocation is a rare injury. There are only a few cases reported in the literature, and most of them are well associated with a predisposing factor. Nettrour and colleagues¹ described the first intrathoracic scapular dislocation, which occurred 6 weeks after sternoclavicular separation and fracture of a rib. In the case reports of Ward and colleagues² and Fowler and colleagues,³ the predisposing factor was resection of the ribs due to pancoast tumor and breast carcinoma, respectively. The mechanism of these dislocations depends on a weak area over the thoracic cage, creating a fulcrum point for levering the scapula into the thoracic cavity.

There are other cases of scapular dislocations that are accompanied by a comminuted fracture of scapula; a review of the literature revealed 3 cases.^4-6 In our opinion, fracture of the inferior pole of the scapula leads to injury of the soft tissues and also results in intrathoracic impaction by creating a weak area over the thoracic cavity. This mechanism can be referred to as penetration.

Our case is singular because it is the first case that is not associated with fracture of the scapula or predisposing factors. Consequently, we report the first pure intrathoracic scapular dislocation in the literature. It is important to suspect intrathoracic scapular dislocation in the case of deformity (Figure 1), even in the absence of any predisposing factors or scapular fracture.

Although plain radiographs may not be elucidative, 3D reconstruction of computed tomography (Figure 2) reveals the pathology and plays an important role in guiding treatment.

In the treatment of our patient, relying on the unique dislocation mechanism without any fracture of the scapula or ribs, we started early active shoulder movement after 1 week of immobilization in a shoulder sling, which prevented recurrence of dislocation. In addition to presenting the first pure intrathoracic scapular dislocation, this case demonstrated satisfactory clinical results with short-term immobilization and early rehabilitation.

Conclusion

Contrary to the literature, the possibility of intrathoracic scapular dislocation should be considered in the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery, and when no fractures are detected. Shoulder or thorax computed tomography, especially 3D reconstructions, are helpful in diagnosing the condition and in guiding treatment. Closed reduction under sedation followed by early rehabilitation is an appropriate treatment method, which resulted in a full return of function in 1 month in our patient.

Scapular dislocation, which is also termed locked scapula or scapulothoracic dislocation, is an unusual condition that can be described as extrathoracic or intrathoracic dislocation, depending on the penetration of scapula into the thoracic cavity.

There have been 3 reported cases of intrathoracic scapular dislocations in the literature,^1-3all associated with a preexisting condition (eg, sternoclavicular separation, prior rib fracture, thoracotomy for a lung transplant procedure, or surgical resection of superior ribs during breast or pulmonary tumor excisions). Three published cases of intrathoracic scapular impaction involve comminuted scapular fractures with intrathoracic impaction of the inferior fragment through intercostal space.^4-6

Here we report an intrathoracic scapular dislocation that was not associated with fracture of the scapula or predisposing factors. To our knowledge, this is the first case of pure intrathoracic dislocation. The possibility of intrathoracic scapular dislocation should be considered as part of the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 29-year-old woman presented to the emergency department after a motor vehicle accident. She had tenderness over the left shoulder and left elbow with decreased range of motion; however, motor and sensory examination of the wrist and fingers were normal. No distal neurovascular deficit was noted.

Physical examination revealed pain on pelvic compression. We observed an asymmetrical appearance between shoulders; the left shoulder was superior when compared with the right side (Figure 1). Palpation of the scapula aggravated the pain. The inferior angle of the left scapula was not palpable, and the medial border was palpated through the intercostal space between the third and fourth ribs.

Initial radiographs showed additional left olecranon and bilateral ramus pubis fractures. A chest radiograph showed nondisplaced fractures of the second and third ribs without any obvious hemothorax or pneumothorax. No other pathology involving the chest, such as resection of the ribs or congenital anomaly, was observed. The patient reported no history of thoracic trauma or lung surgery. There were no fractures of the scapula, humerus, or clavicles. Thoracic computed tomography was performed, and 3-dimensional (3D) reconstruction showed that the inferior angle of scapula penetrated into the thoracic cavity through the third intercostal space (Figure 2).

Given the intrathoracic scapular dislocation diagnosis, closed reduction under sedation was planned. The patient was placed in the supine position, and reduction was performed by applying pressure on the shoulder anteriorly. This maneuver increased deformity. At the same time, another physician pulled the spine of the scapula superiorly, releasing the scapula out of the thoracic cavity. When the arm was slightly lowered to neutral position, scapular deformity was no longer present (Figure 3). A shoulder sling was applied, and the patient was hospitalized for surgical fixation of pelvic and olecranon fractures. The arm was immobilized in a sling for 1 week, and shoulder exercises were started immediately afterward.

At 1-month follow-up, full shoulder range of motion was achieved, although rehabilitation for the elbow continued. Final follow-up examination at 4 months revealed no difference between shoulders, and no recurrence occurred.

Discussion

Intrathoracic scapular dislocation is a rare injury. There are only a few cases reported in the literature, and most of them are well associated with a predisposing factor. Nettrour and colleagues¹ described the first intrathoracic scapular dislocation, which occurred 6 weeks after sternoclavicular separation and fracture of a rib. In the case reports of Ward and colleagues² and Fowler and colleagues,³ the predisposing factor was resection of the ribs due to pancoast tumor and breast carcinoma, respectively. The mechanism of these dislocations depends on a weak area over the thoracic cage, creating a fulcrum point for levering the scapula into the thoracic cavity.

There are other cases of scapular dislocations that are accompanied by a comminuted fracture of scapula; a review of the literature revealed 3 cases.^4-6 In our opinion, fracture of the inferior pole of the scapula leads to injury of the soft tissues and also results in intrathoracic impaction by creating a weak area over the thoracic cavity. This mechanism can be referred to as penetration.

Our case is singular because it is the first case that is not associated with fracture of the scapula or predisposing factors. Consequently, we report the first pure intrathoracic scapular dislocation in the literature. It is important to suspect intrathoracic scapular dislocation in the case of deformity (Figure 1), even in the absence of any predisposing factors or scapular fracture.

Although plain radiographs may not be elucidative, 3D reconstruction of computed tomography (Figure 2) reveals the pathology and plays an important role in guiding treatment.

In the treatment of our patient, relying on the unique dislocation mechanism without any fracture of the scapula or ribs, we started early active shoulder movement after 1 week of immobilization in a shoulder sling, which prevented recurrence of dislocation. In addition to presenting the first pure intrathoracic scapular dislocation, this case demonstrated satisfactory clinical results with short-term immobilization and early rehabilitation.

Conclusion

Contrary to the literature, the possibility of intrathoracic scapular dislocation should be considered in the differential diagnosis even in patients with a negative anamnesis for predisposing factors, such as lung or chest surgery, and when no fractures are detected. Shoulder or thorax computed tomography, especially 3D reconstructions, are helpful in diagnosing the condition and in guiding treatment. Closed reduction under sedation followed by early rehabilitation is an appropriate treatment method, which resulted in a full return of function in 1 month in our patient.

The Internet is becoming a primary source for obtaining medical information. This growing trend may have serious implications for the medical field. As patients increasingly regard the Internet as an essential tool for obtaining health-related information, questions have been raised regarding the quality of medical information available on the Internet.¹ Studies have shown that health-related sites often present inaccurate, inconsistent, and outdated information that may have a negative impact on health care decisions made by patients.²

According to the US Census Bureau, 71.7% of American households report having access to the Internet.³ Of those who have access to Internet, approximately 72% have sought health information online over the last year.⁴ Among people older than age 65 years living in the United States, there has been a growing trend toward using the Internet, from 14% in 2000 to almost 60% in 2013, according to the Pew Research Internet Project.⁵ Most medical websites are viewed for information on diseases and treatment options.⁶ Since most patients want to be informed about treatment options, as well as risks and benefits for each treatment, access to credible information is essential for proper decision-making.⁷

To assess the quality of information on the Internet, we used DISCERN, a standardized questionnaire to aid consumers in judging Internet content.⁸ The DISCERN instrument, available at www.discern.org.uk, was designed by an expert group in the United Kingdom. First, an expert panel developed and tested the instrument, and then health care providers and self-help group members tested it further.^8,9 The questionnaire had been found to have good interrater reliability, regardless of use by health professionals or consumers.^8-10

More than 53,000 shoulder arthroplasties are performed in the United States annually, and the number is growing, with the main goal of pain relief from glenohumeral degenerative joint disease.^11,12 The Internet has become a quasi–second opinion for patients trying to participate in their care. Given the prevalence of shoulder-related surgeries, it is critical to analyze and become familiar with the quality of information that patients read online in order to direct them to nonbiased, all-inclusive websites. In this study, we provide a summary assessment and comparison of the quality of online information pertaining to shoulder replacement, using medical (total shoulder replacement) and nontechnical (shoulder replacement) search terms.

Methods

Websites were identified using 3 search engines (Google, Yahoo, and Bing) and 2 search terms, shoulder replacement (SR) and total shoulder arthroplasty (TSA), on January 17, 2014. These 3 search engines were used because 77% of health care–related information online searches begin through a search engine (Google, Bing, Yahoo); only 13% begin at a health care–specialized website.⁴ These search terms were used after consulting with orthopedic residents and attending physicians in a focus group regarding the terminology used with patients. The first 30 websites in each search engine were identified consecutively and evaluated for category and quality of information using the DISCERN instrument.

A total of 180 websites (90 per search term) were reviewed. Each website was evaluated independently by 3 medical students. In the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram, we recorded how websites were identified, screened, and included (Figure 1).13 Websites that were duplicated within each search term and those that were inaccessible were used to determine the total number of noncommercial versus commercial websites, but were excluded from the final analysis. The first part of the analysis involved determining the type of website (eg, commercial vs noncommercial) based upon the html endings. All .com endings were classified as commercial websites; noncommercial included .gov, .org, .edu, and .net endings. Next, each website was categorized based on the target audience. Websites were grouped into health professional–oriented information, patient-oriented, advertisement, or “other.” These classifications were based on those described in previous works.^14,15 The “other” category included images, YouTube videos, another search engine, and open forums, which were also excluded from the final analysis because they were not easily evaluable with the DISCERN instrument. Websites were considered health professional–oriented if they included journal articles, scholarly articles, and/or rehabilitation protocols. Patient-directed websites clearly stated the information was directed to patients or provided a general overview. Advertisement included sites that displayed ads or products for sale. Websites were evaluated for quality using the DISCERN instrument (Figure 2).

DISCERN has 3 subdivision scores: the reliable score (composed of the first 8 questions), the treatment options (the next 7 questions), and 1 final question that addresses the overall quality of the website and is rated independently of the first 15 questions. DISCERN uses 2 scales, a binary scale anchored on both extremes with the number 1 equaling complete absence of the criteria being measured, and the number 5 at the upper extreme, representing completeness of the quality being assessed. In between 1 and 5 is a partial ordinal scale measuring from 2 to 4, which indicates the information is present to some extent but not complete. The ordinal scale allows ranking of the criteria being assessed. Summarizing values from each of the 2 scales poses some concern: the scale is not a true binary scale because of the ordinal scale of the middle numbers (2-4), and as such, is not amenable to being an interval scale to calculate arithmetic means. To summarize the values from the 2 scales, we calculated the harmonic mean, the arithmetic mean, the geometric mean, and the median. The means were empirically compared with the median, and we used the harmonic mean to summarize scale values because it was the best approximation of the medians.

Results

A total of 90 websites were assessed with the search term total shoulder arthroplasty and another 90 with shoulder replacement. When 37 duplicate websites for TSA and 52 for SR were eliminated, 53 (59%) and 38 (42%) unique websites were evaluated for each search term, respectively (Figure 1). (These unique websites are included in the Appendix.) Between the 2 search terms, 20 websites were duplicated. Figure 3 shows the distribution of websites by category. Total shoulder arthroplasty provided the highest percentage of health professional–oriented information; SR had the greatest percentage of patient-oriented information. Both TSA and SR had nearly the same number of advertisements and websites labeled “other.” The percentage of noncommercial websites from each search engine is represented in Figure 4. For SR, Google had 40% (12/30) noncommercial websites compared with Yahoo at 53% (16/30) and Bing at 46% (14/30). Total shoulder arthroplasty had 43% (13/30) noncommercial websites on Google, 27% (8/30) on Yahoo, and 40% (12/30) on Bing. In total, SR had more noncommercial websites, 47% (42/90), compared with 37% (33/90) for TSA.

The mean of all 3 raters for reliablity (DISCERN questions 1-8) and treatment options (DISCERN questions 9-15) is represented in the Table. For both search terms, we found that websites identified as health professional–oriented had the highest reliable mean scores, followed by patient-oriented, and advertisement at the lowest (SR: P = .054; TSA: P = .134). For SR, treatment mean scores demonstrated similar results with health professional–oriented websites receiving the highest, followed by patient-oriented and advertisement (P = .005). However, the treatment mean scores for TSA differed with patient-oriented websites receiving higher scores than health professional–oriented websites, but this was not statistically significant (P= .407). Regarding search terms, there were no significant differences between mean reliable and treatment scores across all categories.

The average overall DISCERN score for TSA websites was 2.5 (range, 1-5), compared with 2.3 (range, 1-5) for SR websites. The overall reliable score (DISCERN questions 1-8) for TSA websites was 2.6 and 2.5 for SR websites (P < .001). For TSA websites, 38% (20/53) were classified as good, having an overall DISCERN score ≥3, versus 26% (10/38) of SR websites. The overall DISCERN score for health professional–oriented websites was 2.7, patient-oriented websites received a score of 2.6, and advertisements had the lowest score at 2.4.

Discussion

Both patients and health professionals obtain information on health care subjects through the Internet, which has become the primary resource for patients.^15,16 However, there are no strict regulations of the content being written. This creates a challenge for the typical user to find credible and evidence-based information, which is important because misleading information could cause undue anxiety, among other effects.^17,18 The aims of this study were to determine the quality of Internet information for shoulder replacement surgeries using the medical terminology total shoulder arthroplasty (TSA) and the nontechnical term shoulder replacement (SR), and to compare the results.

After analyzing the types of websites returned for both total shoulder arthroplasty and shoulder replacement (Figure 4), it was interesting to find that using nonmedical terminology as the search term provided more noncommercial websites compared with total shoulder arthroplasty. Furthermore, Yahoo provided the highest yield of noncommercial websites at 16, with Bing at 14, when using SR as the search term. We believe the increase in noncommercial websites returned for SR was greater than for TSA because SR yielded more patient-oriented websites, which usually had html endings of .edu and .org, as shown in Figure 3 (48% of SR websites offered patient-oriented information).

Although there were more noncommercial websites for SR, the majority of the DISCERN values between the 2 search terms did not differ significantly. This is a direct result of the number of sites (20) that were duplicated across both search terms. However as seen in the Table, TSA had similar reliable mean scores for advertisements and patient-oriented websites but a slightly higher reliable score for health professional–oriented websites. We correlated this with the increased number of health professional–oriented websites returned when using TSA as the search term (Figure 3). The health professional–oriented websites explained their aims and cited their sources more consistently than did patient-oriented sites and advertisements, resulting in higher reliable scores. Although patient-oriented websites frequently lacked citations, they provided information about multiple treatment options, which were more relevant to consumers. This resulted in nearly equivalent reliable scores. Treatment means for advertisements in both SR and TSA were similar. However, treatment means for professional-oriented websites in TSA were lower than those for SR because health professional–oriented websites often were only moderately relevant to consumers, with their focus usually on 1 treatment option or on rehabilitation protocols. Although the DISCERN scores were similar between the search terms, total shoulder arthroplasty provided more websites (20) classified as good—overall DISCERN score, ≥3—than SR did (10). Advertisement websites had similar overall DISCERN scores, which we anticipated because most of the advertisements were duplicated across the search terms.

Using the 2 search terms, academic websites and commercial websites, such as WebMD, consistently received higher reliable and overall DISCERN scores. Advertisement websites, which need to deliver a clear message, frequently scored high on explicitly stating their aims and relevance to consumers, but focused on their products without discussing the benefits of other treatment options. This is significant because Internet search engines, such as Google, offer sponsor links for which organizations pay to appear at the top of the search results. This creates the potential for consumers to receive biased information because most individuals only visit the top 10 websites generated by a search engine.¹⁹

We concluded that the quality of online information relating to SR and TSA was highly variable and frequently of moderate-to-poor quality, with most overall DISCERN scores <3. The quality of information found online for this study using the DISCERN instrument is consistent with those studies using DISCERN to evaluate other medical conditions (eg, bunions, chronic pain, general anesthesia, and anterior cruciate ligament reconstruction).^2,9,15,19 These studies also concluded that online information varies tremendously in quality and completeness.

This study has several limitations. Websites were searched at a single time point and, because Internet resources are frequently updated, the results of this study could vary. Furthermore, although Google, Yahoo, and Bing are 3 of the most popular search engines, these are not the only resources patients use when searching the Internet for health-related information. Other search engines, such as Pubmed.gov and MSN.com, could provide additional websites for Internet users. Lastly, although DISCERN is validated to address the quality of information available online, it does not evaluate the accuracy of the information.⁸ Our use of DISCERN involves 2 scales, a binary yes/no (ratings, 1 and 5) and an ordinal scale (ratings, 2-4). As such, a single mean summary statistic cannot be calculated.

Conclusion

The information available on the Internet pertaining to TSA and SR is highly variable and provides mostly moderate-to-poor quality information based on the DISCERN instrument. Many websites failed to describe the benefits and the risks of different treatment options, including nonoperative management. Health care professionals should be aware that patients often refer to the Internet as a primary resource for obtaining medical information. It is important to direct patients to websites that provide accurate information, because patients who educate themselves about their conditions and actively participate in decision-making may have improved health outcomes.20-22 Overall, academic websites and commercial websites, such as WebMD and OrthoInfo, generally had higher DISCERN scores when using either search term. Of major concern is the potential for misleading advertisements or incorrect information that can negatively affect health outcomes. This study found that using nonmedical terminology (SR) provided more noncommercial and patient-oriented websites, especially through Yahoo. This study highlights the need for more comprehensive online information pertaining to shoulder replacement that can better serve as a resource for Internet users.

The Internet is becoming a primary source for obtaining medical information. This growing trend may have serious implications for the medical field. As patients increasingly regard the Internet as an essential tool for obtaining health-related information, questions have been raised regarding the quality of medical information available on the Internet.¹ Studies have shown that health-related sites often present inaccurate, inconsistent, and outdated information that may have a negative impact on health care decisions made by patients.²

According to the US Census Bureau, 71.7% of American households report having access to the Internet.³ Of those who have access to Internet, approximately 72% have sought health information online over the last year.⁴ Among people older than age 65 years living in the United States, there has been a growing trend toward using the Internet, from 14% in 2000 to almost 60% in 2013, according to the Pew Research Internet Project.⁵ Most medical websites are viewed for information on diseases and treatment options.⁶ Since most patients want to be informed about treatment options, as well as risks and benefits for each treatment, access to credible information is essential for proper decision-making.⁷

To assess the quality of information on the Internet, we used DISCERN, a standardized questionnaire to aid consumers in judging Internet content.⁸ The DISCERN instrument, available at www.discern.org.uk, was designed by an expert group in the United Kingdom. First, an expert panel developed and tested the instrument, and then health care providers and self-help group members tested it further.^8,9 The questionnaire had been found to have good interrater reliability, regardless of use by health professionals or consumers.^8-10

More than 53,000 shoulder arthroplasties are performed in the United States annually, and the number is growing, with the main goal of pain relief from glenohumeral degenerative joint disease.^11,12 The Internet has become a quasi–second opinion for patients trying to participate in their care. Given the prevalence of shoulder-related surgeries, it is critical to analyze and become familiar with the quality of information that patients read online in order to direct them to nonbiased, all-inclusive websites. In this study, we provide a summary assessment and comparison of the quality of online information pertaining to shoulder replacement, using medical (total shoulder replacement) and nontechnical (shoulder replacement) search terms.

Methods

Websites were identified using 3 search engines (Google, Yahoo, and Bing) and 2 search terms, shoulder replacement (SR) and total shoulder arthroplasty (TSA), on January 17, 2014. These 3 search engines were used because 77% of health care–related information online searches begin through a search engine (Google, Bing, Yahoo); only 13% begin at a health care–specialized website.⁴ These search terms were used after consulting with orthopedic residents and attending physicians in a focus group regarding the terminology used with patients. The first 30 websites in each search engine were identified consecutively and evaluated for category and quality of information using the DISCERN instrument.

A total of 180 websites (90 per search term) were reviewed. Each website was evaluated independently by 3 medical students. In the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram, we recorded how websites were identified, screened, and included (Figure 1).13 Websites that were duplicated within each search term and those that were inaccessible were used to determine the total number of noncommercial versus commercial websites, but were excluded from the final analysis. The first part of the analysis involved determining the type of website (eg, commercial vs noncommercial) based upon the html endings. All .com endings were classified as commercial websites; noncommercial included .gov, .org, .edu, and .net endings. Next, each website was categorized based on the target audience. Websites were grouped into health professional–oriented information, patient-oriented, advertisement, or “other.” These classifications were based on those described in previous works.^14,15 The “other” category included images, YouTube videos, another search engine, and open forums, which were also excluded from the final analysis because they were not easily evaluable with the DISCERN instrument. Websites were considered health professional–oriented if they included journal articles, scholarly articles, and/or rehabilitation protocols. Patient-directed websites clearly stated the information was directed to patients or provided a general overview. Advertisement included sites that displayed ads or products for sale. Websites were evaluated for quality using the DISCERN instrument (Figure 2).

DISCERN has 3 subdivision scores: the reliable score (composed of the first 8 questions), the treatment options (the next 7 questions), and 1 final question that addresses the overall quality of the website and is rated independently of the first 15 questions. DISCERN uses 2 scales, a binary scale anchored on both extremes with the number 1 equaling complete absence of the criteria being measured, and the number 5 at the upper extreme, representing completeness of the quality being assessed. In between 1 and 5 is a partial ordinal scale measuring from 2 to 4, which indicates the information is present to some extent but not complete. The ordinal scale allows ranking of the criteria being assessed. Summarizing values from each of the 2 scales poses some concern: the scale is not a true binary scale because of the ordinal scale of the middle numbers (2-4), and as such, is not amenable to being an interval scale to calculate arithmetic means. To summarize the values from the 2 scales, we calculated the harmonic mean, the arithmetic mean, the geometric mean, and the median. The means were empirically compared with the median, and we used the harmonic mean to summarize scale values because it was the best approximation of the medians.

Results

A total of 90 websites were assessed with the search term total shoulder arthroplasty and another 90 with shoulder replacement. When 37 duplicate websites for TSA and 52 for SR were eliminated, 53 (59%) and 38 (42%) unique websites were evaluated for each search term, respectively (Figure 1). (These unique websites are included in the Appendix.) Between the 2 search terms, 20 websites were duplicated. Figure 3 shows the distribution of websites by category. Total shoulder arthroplasty provided the highest percentage of health professional–oriented information; SR had the greatest percentage of patient-oriented information. Both TSA and SR had nearly the same number of advertisements and websites labeled “other.” The percentage of noncommercial websites from each search engine is represented in Figure 4. For SR, Google had 40% (12/30) noncommercial websites compared with Yahoo at 53% (16/30) and Bing at 46% (14/30). Total shoulder arthroplasty had 43% (13/30) noncommercial websites on Google, 27% (8/30) on Yahoo, and 40% (12/30) on Bing. In total, SR had more noncommercial websites, 47% (42/90), compared with 37% (33/90) for TSA.

The mean of all 3 raters for reliablity (DISCERN questions 1-8) and treatment options (DISCERN questions 9-15) is represented in the Table. For both search terms, we found that websites identified as health professional–oriented had the highest reliable mean scores, followed by patient-oriented, and advertisement at the lowest (SR: P = .054; TSA: P = .134). For SR, treatment mean scores demonstrated similar results with health professional–oriented websites receiving the highest, followed by patient-oriented and advertisement (P = .005). However, the treatment mean scores for TSA differed with patient-oriented websites receiving higher scores than health professional–oriented websites, but this was not statistically significant (P= .407). Regarding search terms, there were no significant differences between mean reliable and treatment scores across all categories.

The average overall DISCERN score for TSA websites was 2.5 (range, 1-5), compared with 2.3 (range, 1-5) for SR websites. The overall reliable score (DISCERN questions 1-8) for TSA websites was 2.6 and 2.5 for SR websites (P < .001). For TSA websites, 38% (20/53) were classified as good, having an overall DISCERN score ≥3, versus 26% (10/38) of SR websites. The overall DISCERN score for health professional–oriented websites was 2.7, patient-oriented websites received a score of 2.6, and advertisements had the lowest score at 2.4.

Discussion

Both patients and health professionals obtain information on health care subjects through the Internet, which has become the primary resource for patients.^15,16 However, there are no strict regulations of the content being written. This creates a challenge for the typical user to find credible and evidence-based information, which is important because misleading information could cause undue anxiety, among other effects.^17,18 The aims of this study were to determine the quality of Internet information for shoulder replacement surgeries using the medical terminology total shoulder arthroplasty (TSA) and the nontechnical term shoulder replacement (SR), and to compare the results.

After analyzing the types of websites returned for both total shoulder arthroplasty and shoulder replacement (Figure 4), it was interesting to find that using nonmedical terminology as the search term provided more noncommercial websites compared with total shoulder arthroplasty. Furthermore, Yahoo provided the highest yield of noncommercial websites at 16, with Bing at 14, when using SR as the search term. We believe the increase in noncommercial websites returned for SR was greater than for TSA because SR yielded more patient-oriented websites, which usually had html endings of .edu and .org, as shown in Figure 3 (48% of SR websites offered patient-oriented information).

Although there were more noncommercial websites for SR, the majority of the DISCERN values between the 2 search terms did not differ significantly. This is a direct result of the number of sites (20) that were duplicated across both search terms. However as seen in the Table, TSA had similar reliable mean scores for advertisements and patient-oriented websites but a slightly higher reliable score for health professional–oriented websites. We correlated this with the increased number of health professional–oriented websites returned when using TSA as the search term (Figure 3). The health professional–oriented websites explained their aims and cited their sources more consistently than did patient-oriented sites and advertisements, resulting in higher reliable scores. Although patient-oriented websites frequently lacked citations, they provided information about multiple treatment options, which were more relevant to consumers. This resulted in nearly equivalent reliable scores. Treatment means for advertisements in both SR and TSA were similar. However, treatment means for professional-oriented websites in TSA were lower than those for SR because health professional–oriented websites often were only moderately relevant to consumers, with their focus usually on 1 treatment option or on rehabilitation protocols. Although the DISCERN scores were similar between the search terms, total shoulder arthroplasty provided more websites (20) classified as good—overall DISCERN score, ≥3—than SR did (10). Advertisement websites had similar overall DISCERN scores, which we anticipated because most of the advertisements were duplicated across the search terms.

Using the 2 search terms, academic websites and commercial websites, such as WebMD, consistently received higher reliable and overall DISCERN scores. Advertisement websites, which need to deliver a clear message, frequently scored high on explicitly stating their aims and relevance to consumers, but focused on their products without discussing the benefits of other treatment options. This is significant because Internet search engines, such as Google, offer sponsor links for which organizations pay to appear at the top of the search results. This creates the potential for consumers to receive biased information because most individuals only visit the top 10 websites generated by a search engine.¹⁹

We concluded that the quality of online information relating to SR and TSA was highly variable and frequently of moderate-to-poor quality, with most overall DISCERN scores <3. The quality of information found online for this study using the DISCERN instrument is consistent with those studies using DISCERN to evaluate other medical conditions (eg, bunions, chronic pain, general anesthesia, and anterior cruciate ligament reconstruction).^2,9,15,19 These studies also concluded that online information varies tremendously in quality and completeness.

This study has several limitations. Websites were searched at a single time point and, because Internet resources are frequently updated, the results of this study could vary. Furthermore, although Google, Yahoo, and Bing are 3 of the most popular search engines, these are not the only resources patients use when searching the Internet for health-related information. Other search engines, such as Pubmed.gov and MSN.com, could provide additional websites for Internet users. Lastly, although DISCERN is validated to address the quality of information available online, it does not evaluate the accuracy of the information.⁸ Our use of DISCERN involves 2 scales, a binary yes/no (ratings, 1 and 5) and an ordinal scale (ratings, 2-4). As such, a single mean summary statistic cannot be calculated.

Conclusion

The information available on the Internet pertaining to TSA and SR is highly variable and provides mostly moderate-to-poor quality information based on the DISCERN instrument. Many websites failed to describe the benefits and the risks of different treatment options, including nonoperative management. Health care professionals should be aware that patients often refer to the Internet as a primary resource for obtaining medical information. It is important to direct patients to websites that provide accurate information, because patients who educate themselves about their conditions and actively participate in decision-making may have improved health outcomes.20-22 Overall, academic websites and commercial websites, such as WebMD and OrthoInfo, generally had higher DISCERN scores when using either search term. Of major concern is the potential for misleading advertisements or incorrect information that can negatively affect health outcomes. This study found that using nonmedical terminology (SR) provided more noncommercial and patient-oriented websites, especially through Yahoo. This study highlights the need for more comprehensive online information pertaining to shoulder replacement that can better serve as a resource for Internet users.

The Internet is becoming a primary source for obtaining medical information. This growing trend may have serious implications for the medical field. As patients increasingly regard the Internet as an essential tool for obtaining health-related information, questions have been raised regarding the quality of medical information available on the Internet.¹ Studies have shown that health-related sites often present inaccurate, inconsistent, and outdated information that may have a negative impact on health care decisions made by patients.²

According to the US Census Bureau, 71.7% of American households report having access to the Internet.³ Of those who have access to Internet, approximately 72% have sought health information online over the last year.⁴ Among people older than age 65 years living in the United States, there has been a growing trend toward using the Internet, from 14% in 2000 to almost 60% in 2013, according to the Pew Research Internet Project.⁵ Most medical websites are viewed for information on diseases and treatment options.⁶ Since most patients want to be informed about treatment options, as well as risks and benefits for each treatment, access to credible information is essential for proper decision-making.⁷

To assess the quality of information on the Internet, we used DISCERN, a standardized questionnaire to aid consumers in judging Internet content.⁸ The DISCERN instrument, available at www.discern.org.uk, was designed by an expert group in the United Kingdom. First, an expert panel developed and tested the instrument, and then health care providers and self-help group members tested it further.^8,9 The questionnaire had been found to have good interrater reliability, regardless of use by health professionals or consumers.^8-10

More than 53,000 shoulder arthroplasties are performed in the United States annually, and the number is growing, with the main goal of pain relief from glenohumeral degenerative joint disease.^11,12 The Internet has become a quasi–second opinion for patients trying to participate in their care. Given the prevalence of shoulder-related surgeries, it is critical to analyze and become familiar with the quality of information that patients read online in order to direct them to nonbiased, all-inclusive websites. In this study, we provide a summary assessment and comparison of the quality of online information pertaining to shoulder replacement, using medical (total shoulder replacement) and nontechnical (shoulder replacement) search terms.

Methods

Websites were identified using 3 search engines (Google, Yahoo, and Bing) and 2 search terms, shoulder replacement (SR) and total shoulder arthroplasty (TSA), on January 17, 2014. These 3 search engines were used because 77% of health care–related information online searches begin through a search engine (Google, Bing, Yahoo); only 13% begin at a health care–specialized website.⁴ These search terms were used after consulting with orthopedic residents and attending physicians in a focus group regarding the terminology used with patients. The first 30 websites in each search engine were identified consecutively and evaluated for category and quality of information using the DISCERN instrument.

A total of 180 websites (90 per search term) were reviewed. Each website was evaluated independently by 3 medical students. In the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram, we recorded how websites were identified, screened, and included (Figure 1).13 Websites that were duplicated within each search term and those that were inaccessible were used to determine the total number of noncommercial versus commercial websites, but were excluded from the final analysis. The first part of the analysis involved determining the type of website (eg, commercial vs noncommercial) based upon the html endings. All .com endings were classified as commercial websites; noncommercial included .gov, .org, .edu, and .net endings. Next, each website was categorized based on the target audience. Websites were grouped into health professional–oriented information, patient-oriented, advertisement, or “other.” These classifications were based on those described in previous works.^14,15 The “other” category included images, YouTube videos, another search engine, and open forums, which were also excluded from the final analysis because they were not easily evaluable with the DISCERN instrument. Websites were considered health professional–oriented if they included journal articles, scholarly articles, and/or rehabilitation protocols. Patient-directed websites clearly stated the information was directed to patients or provided a general overview. Advertisement included sites that displayed ads or products for sale. Websites were evaluated for quality using the DISCERN instrument (Figure 2).

DISCERN has 3 subdivision scores: the reliable score (composed of the first 8 questions), the treatment options (the next 7 questions), and 1 final question that addresses the overall quality of the website and is rated independently of the first 15 questions. DISCERN uses 2 scales, a binary scale anchored on both extremes with the number 1 equaling complete absence of the criteria being measured, and the number 5 at the upper extreme, representing completeness of the quality being assessed. In between 1 and 5 is a partial ordinal scale measuring from 2 to 4, which indicates the information is present to some extent but not complete. The ordinal scale allows ranking of the criteria being assessed. Summarizing values from each of the 2 scales poses some concern: the scale is not a true binary scale because of the ordinal scale of the middle numbers (2-4), and as such, is not amenable to being an interval scale to calculate arithmetic means. To summarize the values from the 2 scales, we calculated the harmonic mean, the arithmetic mean, the geometric mean, and the median. The means were empirically compared with the median, and we used the harmonic mean to summarize scale values because it was the best approximation of the medians.

Results

A total of 90 websites were assessed with the search term total shoulder arthroplasty and another 90 with shoulder replacement. When 37 duplicate websites for TSA and 52 for SR were eliminated, 53 (59%) and 38 (42%) unique websites were evaluated for each search term, respectively (Figure 1). (These unique websites are included in the Appendix.) Between the 2 search terms, 20 websites were duplicated. Figure 3 shows the distribution of websites by category. Total shoulder arthroplasty provided the highest percentage of health professional–oriented information; SR had the greatest percentage of patient-oriented information. Both TSA and SR had nearly the same number of advertisements and websites labeled “other.” The percentage of noncommercial websites from each search engine is represented in Figure 4. For SR, Google had 40% (12/30) noncommercial websites compared with Yahoo at 53% (16/30) and Bing at 46% (14/30). Total shoulder arthroplasty had 43% (13/30) noncommercial websites on Google, 27% (8/30) on Yahoo, and 40% (12/30) on Bing. In total, SR had more noncommercial websites, 47% (42/90), compared with 37% (33/90) for TSA.

The mean of all 3 raters for reliablity (DISCERN questions 1-8) and treatment options (DISCERN questions 9-15) is represented in the Table. For both search terms, we found that websites identified as health professional–oriented had the highest reliable mean scores, followed by patient-oriented, and advertisement at the lowest (SR: P = .054; TSA: P = .134). For SR, treatment mean scores demonstrated similar results with health professional–oriented websites receiving the highest, followed by patient-oriented and advertisement (P = .005). However, the treatment mean scores for TSA differed with patient-oriented websites receiving higher scores than health professional–oriented websites, but this was not statistically significant (P= .407). Regarding search terms, there were no significant differences between mean reliable and treatment scores across all categories.

The average overall DISCERN score for TSA websites was 2.5 (range, 1-5), compared with 2.3 (range, 1-5) for SR websites. The overall reliable score (DISCERN questions 1-8) for TSA websites was 2.6 and 2.5 for SR websites (P < .001). For TSA websites, 38% (20/53) were classified as good, having an overall DISCERN score ≥3, versus 26% (10/38) of SR websites. The overall DISCERN score for health professional–oriented websites was 2.7, patient-oriented websites received a score of 2.6, and advertisements had the lowest score at 2.4.

Discussion

Both patients and health professionals obtain information on health care subjects through the Internet, which has become the primary resource for patients.^15,16 However, there are no strict regulations of the content being written. This creates a challenge for the typical user to find credible and evidence-based information, which is important because misleading information could cause undue anxiety, among other effects.^17,18 The aims of this study were to determine the quality of Internet information for shoulder replacement surgeries using the medical terminology total shoulder arthroplasty (TSA) and the nontechnical term shoulder replacement (SR), and to compare the results.

After analyzing the types of websites returned for both total shoulder arthroplasty and shoulder replacement (Figure 4), it was interesting to find that using nonmedical terminology as the search term provided more noncommercial websites compared with total shoulder arthroplasty. Furthermore, Yahoo provided the highest yield of noncommercial websites at 16, with Bing at 14, when using SR as the search term. We believe the increase in noncommercial websites returned for SR was greater than for TSA because SR yielded more patient-oriented websites, which usually had html endings of .edu and .org, as shown in Figure 3 (48% of SR websites offered patient-oriented information).

Although there were more noncommercial websites for SR, the majority of the DISCERN values between the 2 search terms did not differ significantly. This is a direct result of the number of sites (20) that were duplicated across both search terms. However as seen in the Table, TSA had similar reliable mean scores for advertisements and patient-oriented websites but a slightly higher reliable score for health professional–oriented websites. We correlated this with the increased number of health professional–oriented websites returned when using TSA as the search term (Figure 3). The health professional–oriented websites explained their aims and cited their sources more consistently than did patient-oriented sites and advertisements, resulting in higher reliable scores. Although patient-oriented websites frequently lacked citations, they provided information about multiple treatment options, which were more relevant to consumers. This resulted in nearly equivalent reliable scores. Treatment means for advertisements in both SR and TSA were similar. However, treatment means for professional-oriented websites in TSA were lower than those for SR because health professional–oriented websites often were only moderately relevant to consumers, with their focus usually on 1 treatment option or on rehabilitation protocols. Although the DISCERN scores were similar between the search terms, total shoulder arthroplasty provided more websites (20) classified as good—overall DISCERN score, ≥3—than SR did (10). Advertisement websites had similar overall DISCERN scores, which we anticipated because most of the advertisements were duplicated across the search terms.

Using the 2 search terms, academic websites and commercial websites, such as WebMD, consistently received higher reliable and overall DISCERN scores. Advertisement websites, which need to deliver a clear message, frequently scored high on explicitly stating their aims and relevance to consumers, but focused on their products without discussing the benefits of other treatment options. This is significant because Internet search engines, such as Google, offer sponsor links for which organizations pay to appear at the top of the search results. This creates the potential for consumers to receive biased information because most individuals only visit the top 10 websites generated by a search engine.¹⁹

We concluded that the quality of online information relating to SR and TSA was highly variable and frequently of moderate-to-poor quality, with most overall DISCERN scores <3. The quality of information found online for this study using the DISCERN instrument is consistent with those studies using DISCERN to evaluate other medical conditions (eg, bunions, chronic pain, general anesthesia, and anterior cruciate ligament reconstruction).^2,9,15,19 These studies also concluded that online information varies tremendously in quality and completeness.

This study has several limitations. Websites were searched at a single time point and, because Internet resources are frequently updated, the results of this study could vary. Furthermore, although Google, Yahoo, and Bing are 3 of the most popular search engines, these are not the only resources patients use when searching the Internet for health-related information. Other search engines, such as Pubmed.gov and MSN.com, could provide additional websites for Internet users. Lastly, although DISCERN is validated to address the quality of information available online, it does not evaluate the accuracy of the information.⁸ Our use of DISCERN involves 2 scales, a binary yes/no (ratings, 1 and 5) and an ordinal scale (ratings, 2-4). As such, a single mean summary statistic cannot be calculated.

Conclusion

The information available on the Internet pertaining to TSA and SR is highly variable and provides mostly moderate-to-poor quality information based on the DISCERN instrument. Many websites failed to describe the benefits and the risks of different treatment options, including nonoperative management. Health care professionals should be aware that patients often refer to the Internet as a primary resource for obtaining medical information. It is important to direct patients to websites that provide accurate information, because patients who educate themselves about their conditions and actively participate in decision-making may have improved health outcomes.20-22 Overall, academic websites and commercial websites, such as WebMD and OrthoInfo, generally had higher DISCERN scores when using either search term. Of major concern is the potential for misleading advertisements or incorrect information that can negatively affect health outcomes. This study found that using nonmedical terminology (SR) provided more noncommercial and patient-oriented websites, especially through Yahoo. This study highlights the need for more comprehensive online information pertaining to shoulder replacement that can better serve as a resource for Internet users.

Degenerative arthritis is a widespread chronic condition with an incidence of almost 43 million and annual health care costs of $60 billion in the United States alone.1 Although many cases can be managed symptomatically with medical therapy and intra-articular injections,2 many patients experience disease progression resulting in decreased ambulatory ability and work productivity. For these patients, elective hip and knee arthroplasties can drastically improve quality of life and functionality.3,4 Over the past decade, there has been a marked increase in the number of primary and revision total hip and knee arthroplasties performed in the United States. By 2030, the demand for primary total hip arthroplasties will grow an estimated 174%, to 572,000 procedures. Likewise, the demand for primary total knee arthroplasties is projected to grow by 673%, to 3.48 million procedures.5 However, though better surgical techniques and technology have led to improved functional outcomes, there is still substantial risk for complications in the perioperative period, especially in the geriatric population, in which substantial comorbidities are common.6-9

Acute kidney injury (AKI) is a common public health problem in hospitalized patients and in patients undergoing procedures. More than one-third of all AKI cases occur in surgical settings.^10,11 Over the past decade, both community-acquired and in-hospital AKIs rapidly increased in incidence in all major clinical settings.^12-14 Patients with AKI have high rates of adverse outcomes during hospitalization and discharge.^11,15 Sequelae of AKIs include worsening chronic kidney disease (CKD) and progression to end-stage renal disease, necessitating either long-term dialysis or transplantation.¹² This in turn leads to exacerbated disability, diminished quality of life, and disproportionate burden on health care resources.

Much of our knowledge about postoperative AKI has been derived from cardiovascular, thoracic, and abdominal surgery settings. However, there is a paucity of data on epidemiology and trends for either AKI or associated outcomes in patients undergoing major orthopedic surgery. The few studies to date either were single-center or had inadequate sample sizes for appropriately powered analysis of the risk factors and outcomes related to AKI.¹⁶

In the study reported here, we analyzed a large cohort of patients from a nationwide multicenter database to determine the incidence of and risk factors for AKI. We also examined the mortality and adverse discharges associated with AKI after major joint surgery. Lastly, we assessed temporal trends in both incidence and outcomes of AKI, including the death risk attributable to AKI.

Methods

Database

We extracted our study cohort from the Nationwide Inpatient Sample (NIS) and the National Inpatient Sample of Healthcare Cost and Utilization Project (HCUP) compiled by the Agency for Healthcare Research and Quality.¹⁷ NIS, the largest inpatient care database in the United States, stores data from almost 8 million stays in about 1000 hospitals across the country each year. Its participating hospital pool consists of about 20% of US community hospitals, resulting in a sampling frame comprising about 90% of all hospital discharges in the United States. This allows for calculation of precise, weighted nationwide estimates. Data elements within NIS are drawn from hospital discharge abstracts that indicate all procedures performed. NIS also stores information on patient characteristics, length of stay (LOS), discharge disposition, postoperative morbidity, and observed in-hospital mortality. However, it stores no information on long-term follow-up or complications after discharge.

Data Analysis

For the period 2002–2012, we queried the NIS database for hip and knee arthroplasties with primary diagnosis codes for osteoarthritis and secondary codes for AKI. We excluded patients under age 18 years and patients with diagnosis codes for hip and knee fracture/necrosis, inflammatory/infectious arthritis, or bone neoplasms (Table 1). We then extracted baseline characteristics of the study population. Patient-level characteristics included age, sex, race, quartile classification of median household income according to postal (ZIP) code, and primary payer (Medicare/Medicaid, private insurance, self-pay, no charge). Hospital-level characteristics included hospital location (urban, rural), hospital bed size (small, medium, large), region (Northeast, Midwest/North Central, South, West), and teaching status. We defined illness severity and likelihood of death using Deyo’s modification of the Charlson Comorbidity Index (CCI), which draws on principal and secondary ICD-9-CM (International Classification of Diseases, Ninth Revision-Clinical Modification) diagnosis codes, procedure codes, and patient demographics to estimate a patient’s mortality risk. This method reliably predicts mortality and readmission in the orthopedic population.^18,19 We assessed the effect of AKI on 4 outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of stay. Discharge disposition was grouped by either (a) home or short-term facility or (b) adverse discharge. Home or short-term facility covered routine, short-term hospital, against medical advice, home intravenous provider, another rehabilitation facility, another institution for outpatient services, institution for outpatient services, discharged alive, and destination unknown; adverse discharge covered skilled nursing facility, intermediate care, hospice home, hospice medical facility, long-term care hospital, and certified nursing facility. This dichotomization of discharge disposition is often used in studies of NIS data.²⁰

Statistical Analyses

We compared the baseline characteristics of hospitalized patients with and without AKI. To test for significance, we used the χ² test for categorical variables, the Student t test for normally distributed continuous variables, the Wilcoxon rank sum test for non-normally distributed continuous variables, and the Cochran-Armitage test for trends in AKI incidence. We used survey logistic regression models to calculate adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) in order to estimate the predictors of AKI and the impact of AKI on hospital outcomes. We constructed final models after adjusting for confounders, testing for potential interactions, and ensuring no multicolinearity between covariates. Last, we computed the risk proportion of death attributable to AKI, indicating the proportion of deaths that could potentially be avoided if AKI and its complications were abrogated.²¹

We performed all statistical analyses with SAS Version 9.3 (SAS Institute) using designated weight values to produce weighted national estimates. The threshold for statistical significance was set at P < .01 (with ORs and 95% CIs that excluded 1).

Results

AKI Incidence, Risk Factors, and Trends

We identified 7,235,251 patients who underwent elective hip or knee arthroplasty for osteoarthritis between 2002 and 2012—an estimate consistent with data from the Centers for Disease Control and Prevention.²² Of that total, 94,367 (1.3%) had AKI. The proportion of discharges diagnosed with AKI increased rapidly over the decade, from 0.5% in 2002 to 1.8% to 1.9% in the period 2010–2012. This upward trend was highly significant (P_trend < .001) (Figure 1). Patients with AKI (vs patients without AKI) were more likely to be older (mean age, 70 vs 66 years; P < .001), male (50.8% vs 38.4%; P < .001), and black (10.07% vs 5.15%; P<. 001). They were also found to have a significantly higher comorbidity score (mean CCI, 2.8 vs 1.5; P < .001) and higher proportions of comorbidities, including hypertension, CKD, atrial fibrillation, diabetes mellitus (DM), congestive heart failure, chronic liver disease, and hepatitis C virus infection. In addition, AKI was associated with perioperative myocardial infarction (MI), sepsis, cardiac catheterization, and blood transfusion. Regarding socioeconomic characteristics, patients with AKI were more likely to have Medicare/Medicaid insurance (72.26% vs 58.06%; P < .001) and to belong to the extremes of income categories (Table 2).

Using multivariable logistic regression, we found that increased age (1.11 increase in adjusted OR for every year older; 95% CI, 1.09-1.14; P < .001), male sex (adjusted OR, 1.65; 95% CI, 1.60-1.71; P < .001), and black race (adjusted OR, 1.57; 95% CI, 1.45-1.69; P < .001) were significantly associated with postoperative AKI. Regarding comorbidities, baseline CKD (adjusted OR, 8.64; 95% CI, 8.14-9.18; P < .001) and congestive heart failure (adjusted OR, 2.74; 95% CI, 2.57-2.92; P< .0001) were most significantly associated with AKI. Perioperative events, including sepsis (adjusted OR, 35.64; 95% CI, 30.28-41.96; P < .0001), MI (adjusted OR, 6.14; 95% CI, 5.17-7.28; P < .0001), and blood transfusion (adjusted OR, 2.28; 95% CI, 2.15-2.42; P < .0001), were also strongly associated with postoperative AKI. Last, compared with urban hospitals and small hospital bed size, rural hospitals (adjusted OR, 0.70; 95% CI, 0.60-0.81; P< .001) and large bed size (adjusted OR, 0.82; 95% CI, 0.70-0.93; P = .003) were associated with lower probability of developing AKI (Table 3).

Figure 2 elucidates the frequency of AKI based on a combination of key preoperative comorbid conditions and postoperative complications—demonstrating that the proportion of AKI cases associated with other postoperative complications is significantly higher in the CKD and concomitant DM/CKD patient populations. Patients hospitalized with CKD exhibited higher rates of AKI in cases involving blood transfusion (20.9% vs 1.8%; P < .001), acute MI (48.9% vs 13.8%; P < .001), and sepsis (74.7% vs 36.3%;P< .001) relative to patients without CKD. Similarly, patients with concomitant DM/CKD exhibited higher rates of AKI in cases involving blood transfusion (23% vs 1.9%; P< .001), acute MI (51.1% vs 12.1%; P< .001), and sepsis (75% vs 38.2%; P < .001) relative to patients without either condition. However, patients hospitalized with DM alone exhibited only marginally higher rates of AKI in cases involving blood transfusion (4.7% vs 2%; P < .01) and acute MI (19.2% vs 16.7%; P< .01) and a lower rate in cases involving sepsis (38.2% vs 41.7%; P < .01) relative to patients without DM. These data suggest that CKD is the most significant clinically relevant risk factor for AKI and that CKD may synergize with DM to raise the risk for AKI.

Outcomes

We then analyzed the impact of AKI on hospital outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of care. Mortality was significantly higher in patients with AKI than in patients without it (2.08% vs 0.06%; P < .001). Even after adjusting for confounders (eg, demographics, comorbidity burden, perioperative sepsis, hospital-level characteristics), AKI was still associated with strikingly higher odds of in-hospital death (adjusted OR, 11.32; 95% CI, 9.34-13.74; P < .001). However, analysis of temporal trends indicated that the odds for adjusted mortality associated with AKI decreased from 18.09 to 9.45 (P_trend = .01) over the period 2002–2012 (Figure 3). This decrease in odds of death was countered by an increase in incidence of AKI, resulting in a stable attributable risk proportion (97.9% in 2002 to 97.3% in 2012; P_trend = .90) (Table 4). Regarding discharge disposition, patients with AKI were much less likely to be discharged home (41.35% vs 62.59%; P < .001) and more likely to be discharged to long-term care (56.37% vs 37.03%; P< .001). After adjustment for confounders, AKI was associated with significantly increased odds of adverse discharge (adjusted OR, 2.24; 95% CI, 2.12-2.36; P< .001). Analysis of temporal trends revealed no appreciable decrease in the adjusted odds of adverse discharge between 2002 (adjusted OR, 1.87; 95% CI, 1.37-2.55; P < .001) and 2012 (adjusted OR, 1.93; 95% CI, 1.76-2.11; P < .001) (Figure 4, Table 5). Last, both mean LOS (5 days vs 3 days; P < .001) and mean cost of hospitalization (US $22,269 vs $15,757; P < .001) were significantly higher in patients with AKI.

Discussion

In this study, we found that the incidence of AKI among hospitalized patients increased 4-fold between 2002 and 2012. Moreover, we identified numerous patient-specific, hospital-specific, perioperative risk factors for AKI. Most important, we found that AKI was associated with a strikingly higher risk of in-hospital death, and surviving patients were more likely to experience adverse discharge. Although the adjusted mortality rate associated with AKI decreased over that decade, the attributable risk proportion remained stable.

Few studies have addressed this significant public health concern. In one recent study in Australia, Kimmel and colleagues¹⁶ identified risk factors for AKI but lacked data on AKI outcomes. In a study of complications and mortality occurring after orthopedic surgery, Belmont and colleagues²² categorized complications as either local or systemic but did not examine renal complications. Only 2 other major studies have been conducted on renal outcomes associated with major joint surgery, and both were limited to patients with acute hip fractures. The first included acute fracture surgery patients and omitted elective joint surgery patients, and it evaluated admission renal function but not postoperative AKI.²² The second study had a sample size of only 170 patients.²³ Thus, the literature leaves us with a crucial knowledge gap in renal outcomes and their postoperative impact in elective arthroplasties.

The present study filled this information gap by examining the incidence, risk factors, outcomes, and temporal trends of AKI after elective hip and knee arthroplasties. The increasing incidence of AKI in this surgical setting is similar to that of AKI in other surgical settings (cardiac and noncardiac).²¹ Although our analysis was limited by lack of perioperative management data, patients undergoing elective joint arthroplasty can experience kidney dysfunction for several reasons, including volume depletion, postoperative sepsis, and influence of medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), especially in older patients with more comorbidities and a higher burden of CKD. Each of these factors can cause renal dysfunction in patients having orthopedic procedures.²⁴ Moreover, NSAID use among elective joint arthroplasty patients is likely higher because of an emphasis on multimodal analgesia, as recent randomized controlled trials have demonstrated the efficacy of NSAID use in controlling pain without increasing bleeding.^25-27 Our results also demonstrated that the absolute incidence of AKI after orthopedic surgery is relatively low. One possible explanation for this phenomenon is that the definitions used were based on ICD-9-CM codes that underestimate the true incidence of AKI.

Consistent with other studies, we found that certain key preoperative comorbid conditions and postoperative events were associated with higher AKI risk. We stratified the rate of AKI associated with each postoperative event (sepsis, acute MI, cardiac catheterization, need for transfusion) by DM/CKD comorbidity. CKD was associated with significantly higher AKI risk across all postoperative complications. This information may provide clinicians with bedside information that can be used to determine which patients may be at higher or lower risk for AKI.

Our analysis of patient outcomes revealed that, though AKI was relatively uncommon, it increased the risk for death during hospitalization more than 10-fold between 2002 and 2012. Although the adjusted OR of in-hospital mortality decreased over the decade studied, the concurrent increase in AKI incidence caused the attributable risk of death associated with AKI to essentially remain the same. This observation is consistent with recent reports from cardiac surgery settings.²¹ These data together suggest that ameliorating occurrences of AKI would decrease mortality and increase quality of care for patients undergoing elective joint surgeries.

We also examined the effect of AKI on resource use by studying LOS, costs, and risk for adverse discharge. Much as in other surgical settings, AKI increased both LOS and overall hospitalization costs. More important, AKI was associated with increased adverse discharge (discharge to long-term care or nursing homes). Although exact reasons are unclear, we can speculate that postoperative renal dysfunction precludes early rehabilitation, impeding desired functional outcome and disposition.^28,29 Given the projected increases in primary and revision hip and knee arthroplasties,⁵ these data predict that the impact of AKI on health outcomes will increase alarmingly in coming years.

There are limitations to our study. First, it was based on administrative data and lacked patient-level and laboratory data. As reported, the sensitivity of AKI codes remains moderate,³⁰ so the true burden may be higher than indicated here. As the definition of AKI was based on administrative coding, we also could not estimate severity, though previous studies have found that administrative codes typically capture a more severe form of disease.³¹ Another limitation is that, because the data were deidentified, we could not delineate the risk for recurrent AKI in repeated surgical procedures, though this cohort unlikely was large enough to qualitatively affect our results. The third limitation is that, though we used CCI to adjust for the comorbidity burden, we were unable to account for other unmeasured confounders associated with increased AKI incidence, such as specific medication use. In addition, given the lack of patient-level data, we could not analyze the specific factors responsible for AKI in the perioperative period. Nevertheless, the strengths of a nationally representative sample, such as large sample size and generalizability, outweigh these limitations.

Conclusion

AKI is potentially an important quality indicator of elective joint surgery, and reducing its incidence is therefore essential for quality improvement. Given that hip and knee arthroplasties are projected to increase exponentially, as is the burden of comorbid conditions in this population, postoperative AKI will continue to have an incremental impact on health and health care resources. Thus, a carefully planned approach of interdisciplinary perioperative care is warranted to reduce both the risk and the consequences of this devastating condition.

Degenerative arthritis is a widespread chronic condition with an incidence of almost 43 million and annual health care costs of $60 billion in the United States alone.1 Although many cases can be managed symptomatically with medical therapy and intra-articular injections,2 many patients experience disease progression resulting in decreased ambulatory ability and work productivity. For these patients, elective hip and knee arthroplasties can drastically improve quality of life and functionality.3,4 Over the past decade, there has been a marked increase in the number of primary and revision total hip and knee arthroplasties performed in the United States. By 2030, the demand for primary total hip arthroplasties will grow an estimated 174%, to 572,000 procedures. Likewise, the demand for primary total knee arthroplasties is projected to grow by 673%, to 3.48 million procedures.5 However, though better surgical techniques and technology have led to improved functional outcomes, there is still substantial risk for complications in the perioperative period, especially in the geriatric population, in which substantial comorbidities are common.6-9

Acute kidney injury (AKI) is a common public health problem in hospitalized patients and in patients undergoing procedures. More than one-third of all AKI cases occur in surgical settings.^10,11 Over the past decade, both community-acquired and in-hospital AKIs rapidly increased in incidence in all major clinical settings.^12-14 Patients with AKI have high rates of adverse outcomes during hospitalization and discharge.^11,15 Sequelae of AKIs include worsening chronic kidney disease (CKD) and progression to end-stage renal disease, necessitating either long-term dialysis or transplantation.¹² This in turn leads to exacerbated disability, diminished quality of life, and disproportionate burden on health care resources.

Much of our knowledge about postoperative AKI has been derived from cardiovascular, thoracic, and abdominal surgery settings. However, there is a paucity of data on epidemiology and trends for either AKI or associated outcomes in patients undergoing major orthopedic surgery. The few studies to date either were single-center or had inadequate sample sizes for appropriately powered analysis of the risk factors and outcomes related to AKI.¹⁶

In the study reported here, we analyzed a large cohort of patients from a nationwide multicenter database to determine the incidence of and risk factors for AKI. We also examined the mortality and adverse discharges associated with AKI after major joint surgery. Lastly, we assessed temporal trends in both incidence and outcomes of AKI, including the death risk attributable to AKI.

Methods

Database

We extracted our study cohort from the Nationwide Inpatient Sample (NIS) and the National Inpatient Sample of Healthcare Cost and Utilization Project (HCUP) compiled by the Agency for Healthcare Research and Quality.¹⁷ NIS, the largest inpatient care database in the United States, stores data from almost 8 million stays in about 1000 hospitals across the country each year. Its participating hospital pool consists of about 20% of US community hospitals, resulting in a sampling frame comprising about 90% of all hospital discharges in the United States. This allows for calculation of precise, weighted nationwide estimates. Data elements within NIS are drawn from hospital discharge abstracts that indicate all procedures performed. NIS also stores information on patient characteristics, length of stay (LOS), discharge disposition, postoperative morbidity, and observed in-hospital mortality. However, it stores no information on long-term follow-up or complications after discharge.

Data Analysis

For the period 2002–2012, we queried the NIS database for hip and knee arthroplasties with primary diagnosis codes for osteoarthritis and secondary codes for AKI. We excluded patients under age 18 years and patients with diagnosis codes for hip and knee fracture/necrosis, inflammatory/infectious arthritis, or bone neoplasms (Table 1). We then extracted baseline characteristics of the study population. Patient-level characteristics included age, sex, race, quartile classification of median household income according to postal (ZIP) code, and primary payer (Medicare/Medicaid, private insurance, self-pay, no charge). Hospital-level characteristics included hospital location (urban, rural), hospital bed size (small, medium, large), region (Northeast, Midwest/North Central, South, West), and teaching status. We defined illness severity and likelihood of death using Deyo’s modification of the Charlson Comorbidity Index (CCI), which draws on principal and secondary ICD-9-CM (International Classification of Diseases, Ninth Revision-Clinical Modification) diagnosis codes, procedure codes, and patient demographics to estimate a patient’s mortality risk. This method reliably predicts mortality and readmission in the orthopedic population.^18,19 We assessed the effect of AKI on 4 outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of stay. Discharge disposition was grouped by either (a) home or short-term facility or (b) adverse discharge. Home or short-term facility covered routine, short-term hospital, against medical advice, home intravenous provider, another rehabilitation facility, another institution for outpatient services, institution for outpatient services, discharged alive, and destination unknown; adverse discharge covered skilled nursing facility, intermediate care, hospice home, hospice medical facility, long-term care hospital, and certified nursing facility. This dichotomization of discharge disposition is often used in studies of NIS data.²⁰

Statistical Analyses

We compared the baseline characteristics of hospitalized patients with and without AKI. To test for significance, we used the χ² test for categorical variables, the Student t test for normally distributed continuous variables, the Wilcoxon rank sum test for non-normally distributed continuous variables, and the Cochran-Armitage test for trends in AKI incidence. We used survey logistic regression models to calculate adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) in order to estimate the predictors of AKI and the impact of AKI on hospital outcomes. We constructed final models after adjusting for confounders, testing for potential interactions, and ensuring no multicolinearity between covariates. Last, we computed the risk proportion of death attributable to AKI, indicating the proportion of deaths that could potentially be avoided if AKI and its complications were abrogated.²¹

We performed all statistical analyses with SAS Version 9.3 (SAS Institute) using designated weight values to produce weighted national estimates. The threshold for statistical significance was set at P < .01 (with ORs and 95% CIs that excluded 1).

Results

AKI Incidence, Risk Factors, and Trends

We identified 7,235,251 patients who underwent elective hip or knee arthroplasty for osteoarthritis between 2002 and 2012—an estimate consistent with data from the Centers for Disease Control and Prevention.²² Of that total, 94,367 (1.3%) had AKI. The proportion of discharges diagnosed with AKI increased rapidly over the decade, from 0.5% in 2002 to 1.8% to 1.9% in the period 2010–2012. This upward trend was highly significant (P_trend < .001) (Figure 1). Patients with AKI (vs patients without AKI) were more likely to be older (mean age, 70 vs 66 years; P < .001), male (50.8% vs 38.4%; P < .001), and black (10.07% vs 5.15%; P<. 001). They were also found to have a significantly higher comorbidity score (mean CCI, 2.8 vs 1.5; P < .001) and higher proportions of comorbidities, including hypertension, CKD, atrial fibrillation, diabetes mellitus (DM), congestive heart failure, chronic liver disease, and hepatitis C virus infection. In addition, AKI was associated with perioperative myocardial infarction (MI), sepsis, cardiac catheterization, and blood transfusion. Regarding socioeconomic characteristics, patients with AKI were more likely to have Medicare/Medicaid insurance (72.26% vs 58.06%; P < .001) and to belong to the extremes of income categories (Table 2).

Using multivariable logistic regression, we found that increased age (1.11 increase in adjusted OR for every year older; 95% CI, 1.09-1.14; P < .001), male sex (adjusted OR, 1.65; 95% CI, 1.60-1.71; P < .001), and black race (adjusted OR, 1.57; 95% CI, 1.45-1.69; P < .001) were significantly associated with postoperative AKI. Regarding comorbidities, baseline CKD (adjusted OR, 8.64; 95% CI, 8.14-9.18; P < .001) and congestive heart failure (adjusted OR, 2.74; 95% CI, 2.57-2.92; P< .0001) were most significantly associated with AKI. Perioperative events, including sepsis (adjusted OR, 35.64; 95% CI, 30.28-41.96; P < .0001), MI (adjusted OR, 6.14; 95% CI, 5.17-7.28; P < .0001), and blood transfusion (adjusted OR, 2.28; 95% CI, 2.15-2.42; P < .0001), were also strongly associated with postoperative AKI. Last, compared with urban hospitals and small hospital bed size, rural hospitals (adjusted OR, 0.70; 95% CI, 0.60-0.81; P< .001) and large bed size (adjusted OR, 0.82; 95% CI, 0.70-0.93; P = .003) were associated with lower probability of developing AKI (Table 3).

Figure 2 elucidates the frequency of AKI based on a combination of key preoperative comorbid conditions and postoperative complications—demonstrating that the proportion of AKI cases associated with other postoperative complications is significantly higher in the CKD and concomitant DM/CKD patient populations. Patients hospitalized with CKD exhibited higher rates of AKI in cases involving blood transfusion (20.9% vs 1.8%; P < .001), acute MI (48.9% vs 13.8%; P < .001), and sepsis (74.7% vs 36.3%;P< .001) relative to patients without CKD. Similarly, patients with concomitant DM/CKD exhibited higher rates of AKI in cases involving blood transfusion (23% vs 1.9%; P< .001), acute MI (51.1% vs 12.1%; P< .001), and sepsis (75% vs 38.2%; P < .001) relative to patients without either condition. However, patients hospitalized with DM alone exhibited only marginally higher rates of AKI in cases involving blood transfusion (4.7% vs 2%; P < .01) and acute MI (19.2% vs 16.7%; P< .01) and a lower rate in cases involving sepsis (38.2% vs 41.7%; P < .01) relative to patients without DM. These data suggest that CKD is the most significant clinically relevant risk factor for AKI and that CKD may synergize with DM to raise the risk for AKI.

Outcomes

We then analyzed the impact of AKI on hospital outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of care. Mortality was significantly higher in patients with AKI than in patients without it (2.08% vs 0.06%; P < .001). Even after adjusting for confounders (eg, demographics, comorbidity burden, perioperative sepsis, hospital-level characteristics), AKI was still associated with strikingly higher odds of in-hospital death (adjusted OR, 11.32; 95% CI, 9.34-13.74; P < .001). However, analysis of temporal trends indicated that the odds for adjusted mortality associated with AKI decreased from 18.09 to 9.45 (P_trend = .01) over the period 2002–2012 (Figure 3). This decrease in odds of death was countered by an increase in incidence of AKI, resulting in a stable attributable risk proportion (97.9% in 2002 to 97.3% in 2012; P_trend = .90) (Table 4). Regarding discharge disposition, patients with AKI were much less likely to be discharged home (41.35% vs 62.59%; P < .001) and more likely to be discharged to long-term care (56.37% vs 37.03%; P< .001). After adjustment for confounders, AKI was associated with significantly increased odds of adverse discharge (adjusted OR, 2.24; 95% CI, 2.12-2.36; P< .001). Analysis of temporal trends revealed no appreciable decrease in the adjusted odds of adverse discharge between 2002 (adjusted OR, 1.87; 95% CI, 1.37-2.55; P < .001) and 2012 (adjusted OR, 1.93; 95% CI, 1.76-2.11; P < .001) (Figure 4, Table 5). Last, both mean LOS (5 days vs 3 days; P < .001) and mean cost of hospitalization (US $22,269 vs $15,757; P < .001) were significantly higher in patients with AKI.

Discussion

In this study, we found that the incidence of AKI among hospitalized patients increased 4-fold between 2002 and 2012. Moreover, we identified numerous patient-specific, hospital-specific, perioperative risk factors for AKI. Most important, we found that AKI was associated with a strikingly higher risk of in-hospital death, and surviving patients were more likely to experience adverse discharge. Although the adjusted mortality rate associated with AKI decreased over that decade, the attributable risk proportion remained stable.

Few studies have addressed this significant public health concern. In one recent study in Australia, Kimmel and colleagues¹⁶ identified risk factors for AKI but lacked data on AKI outcomes. In a study of complications and mortality occurring after orthopedic surgery, Belmont and colleagues²² categorized complications as either local or systemic but did not examine renal complications. Only 2 other major studies have been conducted on renal outcomes associated with major joint surgery, and both were limited to patients with acute hip fractures. The first included acute fracture surgery patients and omitted elective joint surgery patients, and it evaluated admission renal function but not postoperative AKI.²² The second study had a sample size of only 170 patients.²³ Thus, the literature leaves us with a crucial knowledge gap in renal outcomes and their postoperative impact in elective arthroplasties.

The present study filled this information gap by examining the incidence, risk factors, outcomes, and temporal trends of AKI after elective hip and knee arthroplasties. The increasing incidence of AKI in this surgical setting is similar to that of AKI in other surgical settings (cardiac and noncardiac).²¹ Although our analysis was limited by lack of perioperative management data, patients undergoing elective joint arthroplasty can experience kidney dysfunction for several reasons, including volume depletion, postoperative sepsis, and influence of medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), especially in older patients with more comorbidities and a higher burden of CKD. Each of these factors can cause renal dysfunction in patients having orthopedic procedures.²⁴ Moreover, NSAID use among elective joint arthroplasty patients is likely higher because of an emphasis on multimodal analgesia, as recent randomized controlled trials have demonstrated the efficacy of NSAID use in controlling pain without increasing bleeding.^25-27 Our results also demonstrated that the absolute incidence of AKI after orthopedic surgery is relatively low. One possible explanation for this phenomenon is that the definitions used were based on ICD-9-CM codes that underestimate the true incidence of AKI.

Consistent with other studies, we found that certain key preoperative comorbid conditions and postoperative events were associated with higher AKI risk. We stratified the rate of AKI associated with each postoperative event (sepsis, acute MI, cardiac catheterization, need for transfusion) by DM/CKD comorbidity. CKD was associated with significantly higher AKI risk across all postoperative complications. This information may provide clinicians with bedside information that can be used to determine which patients may be at higher or lower risk for AKI.

Our analysis of patient outcomes revealed that, though AKI was relatively uncommon, it increased the risk for death during hospitalization more than 10-fold between 2002 and 2012. Although the adjusted OR of in-hospital mortality decreased over the decade studied, the concurrent increase in AKI incidence caused the attributable risk of death associated with AKI to essentially remain the same. This observation is consistent with recent reports from cardiac surgery settings.²¹ These data together suggest that ameliorating occurrences of AKI would decrease mortality and increase quality of care for patients undergoing elective joint surgeries.

We also examined the effect of AKI on resource use by studying LOS, costs, and risk for adverse discharge. Much as in other surgical settings, AKI increased both LOS and overall hospitalization costs. More important, AKI was associated with increased adverse discharge (discharge to long-term care or nursing homes). Although exact reasons are unclear, we can speculate that postoperative renal dysfunction precludes early rehabilitation, impeding desired functional outcome and disposition.^28,29 Given the projected increases in primary and revision hip and knee arthroplasties,⁵ these data predict that the impact of AKI on health outcomes will increase alarmingly in coming years.

There are limitations to our study. First, it was based on administrative data and lacked patient-level and laboratory data. As reported, the sensitivity of AKI codes remains moderate,³⁰ so the true burden may be higher than indicated here. As the definition of AKI was based on administrative coding, we also could not estimate severity, though previous studies have found that administrative codes typically capture a more severe form of disease.³¹ Another limitation is that, because the data were deidentified, we could not delineate the risk for recurrent AKI in repeated surgical procedures, though this cohort unlikely was large enough to qualitatively affect our results. The third limitation is that, though we used CCI to adjust for the comorbidity burden, we were unable to account for other unmeasured confounders associated with increased AKI incidence, such as specific medication use. In addition, given the lack of patient-level data, we could not analyze the specific factors responsible for AKI in the perioperative period. Nevertheless, the strengths of a nationally representative sample, such as large sample size and generalizability, outweigh these limitations.

Conclusion

AKI is potentially an important quality indicator of elective joint surgery, and reducing its incidence is therefore essential for quality improvement. Given that hip and knee arthroplasties are projected to increase exponentially, as is the burden of comorbid conditions in this population, postoperative AKI will continue to have an incremental impact on health and health care resources. Thus, a carefully planned approach of interdisciplinary perioperative care is warranted to reduce both the risk and the consequences of this devastating condition.

Degenerative arthritis is a widespread chronic condition with an incidence of almost 43 million and annual health care costs of $60 billion in the United States alone.1 Although many cases can be managed symptomatically with medical therapy and intra-articular injections,2 many patients experience disease progression resulting in decreased ambulatory ability and work productivity. For these patients, elective hip and knee arthroplasties can drastically improve quality of life and functionality.3,4 Over the past decade, there has been a marked increase in the number of primary and revision total hip and knee arthroplasties performed in the United States. By 2030, the demand for primary total hip arthroplasties will grow an estimated 174%, to 572,000 procedures. Likewise, the demand for primary total knee arthroplasties is projected to grow by 673%, to 3.48 million procedures.5 However, though better surgical techniques and technology have led to improved functional outcomes, there is still substantial risk for complications in the perioperative period, especially in the geriatric population, in which substantial comorbidities are common.6-9

Acute kidney injury (AKI) is a common public health problem in hospitalized patients and in patients undergoing procedures. More than one-third of all AKI cases occur in surgical settings.^10,11 Over the past decade, both community-acquired and in-hospital AKIs rapidly increased in incidence in all major clinical settings.^12-14 Patients with AKI have high rates of adverse outcomes during hospitalization and discharge.^11,15 Sequelae of AKIs include worsening chronic kidney disease (CKD) and progression to end-stage renal disease, necessitating either long-term dialysis or transplantation.¹² This in turn leads to exacerbated disability, diminished quality of life, and disproportionate burden on health care resources.

Much of our knowledge about postoperative AKI has been derived from cardiovascular, thoracic, and abdominal surgery settings. However, there is a paucity of data on epidemiology and trends for either AKI or associated outcomes in patients undergoing major orthopedic surgery. The few studies to date either were single-center or had inadequate sample sizes for appropriately powered analysis of the risk factors and outcomes related to AKI.¹⁶

In the study reported here, we analyzed a large cohort of patients from a nationwide multicenter database to determine the incidence of and risk factors for AKI. We also examined the mortality and adverse discharges associated with AKI after major joint surgery. Lastly, we assessed temporal trends in both incidence and outcomes of AKI, including the death risk attributable to AKI.

Methods

Database

We extracted our study cohort from the Nationwide Inpatient Sample (NIS) and the National Inpatient Sample of Healthcare Cost and Utilization Project (HCUP) compiled by the Agency for Healthcare Research and Quality.¹⁷ NIS, the largest inpatient care database in the United States, stores data from almost 8 million stays in about 1000 hospitals across the country each year. Its participating hospital pool consists of about 20% of US community hospitals, resulting in a sampling frame comprising about 90% of all hospital discharges in the United States. This allows for calculation of precise, weighted nationwide estimates. Data elements within NIS are drawn from hospital discharge abstracts that indicate all procedures performed. NIS also stores information on patient characteristics, length of stay (LOS), discharge disposition, postoperative morbidity, and observed in-hospital mortality. However, it stores no information on long-term follow-up or complications after discharge.

Data Analysis

For the period 2002–2012, we queried the NIS database for hip and knee arthroplasties with primary diagnosis codes for osteoarthritis and secondary codes for AKI. We excluded patients under age 18 years and patients with diagnosis codes for hip and knee fracture/necrosis, inflammatory/infectious arthritis, or bone neoplasms (Table 1). We then extracted baseline characteristics of the study population. Patient-level characteristics included age, sex, race, quartile classification of median household income according to postal (ZIP) code, and primary payer (Medicare/Medicaid, private insurance, self-pay, no charge). Hospital-level characteristics included hospital location (urban, rural), hospital bed size (small, medium, large), region (Northeast, Midwest/North Central, South, West), and teaching status. We defined illness severity and likelihood of death using Deyo’s modification of the Charlson Comorbidity Index (CCI), which draws on principal and secondary ICD-9-CM (International Classification of Diseases, Ninth Revision-Clinical Modification) diagnosis codes, procedure codes, and patient demographics to estimate a patient’s mortality risk. This method reliably predicts mortality and readmission in the orthopedic population.^18,19 We assessed the effect of AKI on 4 outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of stay. Discharge disposition was grouped by either (a) home or short-term facility or (b) adverse discharge. Home or short-term facility covered routine, short-term hospital, against medical advice, home intravenous provider, another rehabilitation facility, another institution for outpatient services, institution for outpatient services, discharged alive, and destination unknown; adverse discharge covered skilled nursing facility, intermediate care, hospice home, hospice medical facility, long-term care hospital, and certified nursing facility. This dichotomization of discharge disposition is often used in studies of NIS data.²⁰

Statistical Analyses

We compared the baseline characteristics of hospitalized patients with and without AKI. To test for significance, we used the χ² test for categorical variables, the Student t test for normally distributed continuous variables, the Wilcoxon rank sum test for non-normally distributed continuous variables, and the Cochran-Armitage test for trends in AKI incidence. We used survey logistic regression models to calculate adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) in order to estimate the predictors of AKI and the impact of AKI on hospital outcomes. We constructed final models after adjusting for confounders, testing for potential interactions, and ensuring no multicolinearity between covariates. Last, we computed the risk proportion of death attributable to AKI, indicating the proportion of deaths that could potentially be avoided if AKI and its complications were abrogated.²¹

We performed all statistical analyses with SAS Version 9.3 (SAS Institute) using designated weight values to produce weighted national estimates. The threshold for statistical significance was set at P < .01 (with ORs and 95% CIs that excluded 1).

Results

AKI Incidence, Risk Factors, and Trends

We identified 7,235,251 patients who underwent elective hip or knee arthroplasty for osteoarthritis between 2002 and 2012—an estimate consistent with data from the Centers for Disease Control and Prevention.²² Of that total, 94,367 (1.3%) had AKI. The proportion of discharges diagnosed with AKI increased rapidly over the decade, from 0.5% in 2002 to 1.8% to 1.9% in the period 2010–2012. This upward trend was highly significant (P_trend < .001) (Figure 1). Patients with AKI (vs patients without AKI) were more likely to be older (mean age, 70 vs 66 years; P < .001), male (50.8% vs 38.4%; P < .001), and black (10.07% vs 5.15%; P<. 001). They were also found to have a significantly higher comorbidity score (mean CCI, 2.8 vs 1.5; P < .001) and higher proportions of comorbidities, including hypertension, CKD, atrial fibrillation, diabetes mellitus (DM), congestive heart failure, chronic liver disease, and hepatitis C virus infection. In addition, AKI was associated with perioperative myocardial infarction (MI), sepsis, cardiac catheterization, and blood transfusion. Regarding socioeconomic characteristics, patients with AKI were more likely to have Medicare/Medicaid insurance (72.26% vs 58.06%; P < .001) and to belong to the extremes of income categories (Table 2).

Using multivariable logistic regression, we found that increased age (1.11 increase in adjusted OR for every year older; 95% CI, 1.09-1.14; P < .001), male sex (adjusted OR, 1.65; 95% CI, 1.60-1.71; P < .001), and black race (adjusted OR, 1.57; 95% CI, 1.45-1.69; P < .001) were significantly associated with postoperative AKI. Regarding comorbidities, baseline CKD (adjusted OR, 8.64; 95% CI, 8.14-9.18; P < .001) and congestive heart failure (adjusted OR, 2.74; 95% CI, 2.57-2.92; P< .0001) were most significantly associated with AKI. Perioperative events, including sepsis (adjusted OR, 35.64; 95% CI, 30.28-41.96; P < .0001), MI (adjusted OR, 6.14; 95% CI, 5.17-7.28; P < .0001), and blood transfusion (adjusted OR, 2.28; 95% CI, 2.15-2.42; P < .0001), were also strongly associated with postoperative AKI. Last, compared with urban hospitals and small hospital bed size, rural hospitals (adjusted OR, 0.70; 95% CI, 0.60-0.81; P< .001) and large bed size (adjusted OR, 0.82; 95% CI, 0.70-0.93; P = .003) were associated with lower probability of developing AKI (Table 3).

Figure 2 elucidates the frequency of AKI based on a combination of key preoperative comorbid conditions and postoperative complications—demonstrating that the proportion of AKI cases associated with other postoperative complications is significantly higher in the CKD and concomitant DM/CKD patient populations. Patients hospitalized with CKD exhibited higher rates of AKI in cases involving blood transfusion (20.9% vs 1.8%; P < .001), acute MI (48.9% vs 13.8%; P < .001), and sepsis (74.7% vs 36.3%;P< .001) relative to patients without CKD. Similarly, patients with concomitant DM/CKD exhibited higher rates of AKI in cases involving blood transfusion (23% vs 1.9%; P< .001), acute MI (51.1% vs 12.1%; P< .001), and sepsis (75% vs 38.2%; P < .001) relative to patients without either condition. However, patients hospitalized with DM alone exhibited only marginally higher rates of AKI in cases involving blood transfusion (4.7% vs 2%; P < .01) and acute MI (19.2% vs 16.7%; P< .01) and a lower rate in cases involving sepsis (38.2% vs 41.7%; P < .01) relative to patients without DM. These data suggest that CKD is the most significant clinically relevant risk factor for AKI and that CKD may synergize with DM to raise the risk for AKI.

Outcomes

We then analyzed the impact of AKI on hospital outcomes, including in-hospital mortality, discharge disposition, LOS, and cost of care. Mortality was significantly higher in patients with AKI than in patients without it (2.08% vs 0.06%; P < .001). Even after adjusting for confounders (eg, demographics, comorbidity burden, perioperative sepsis, hospital-level characteristics), AKI was still associated with strikingly higher odds of in-hospital death (adjusted OR, 11.32; 95% CI, 9.34-13.74; P < .001). However, analysis of temporal trends indicated that the odds for adjusted mortality associated with AKI decreased from 18.09 to 9.45 (P_trend = .01) over the period 2002–2012 (Figure 3). This decrease in odds of death was countered by an increase in incidence of AKI, resulting in a stable attributable risk proportion (97.9% in 2002 to 97.3% in 2012; P_trend = .90) (Table 4). Regarding discharge disposition, patients with AKI were much less likely to be discharged home (41.35% vs 62.59%; P < .001) and more likely to be discharged to long-term care (56.37% vs 37.03%; P< .001). After adjustment for confounders, AKI was associated with significantly increased odds of adverse discharge (adjusted OR, 2.24; 95% CI, 2.12-2.36; P< .001). Analysis of temporal trends revealed no appreciable decrease in the adjusted odds of adverse discharge between 2002 (adjusted OR, 1.87; 95% CI, 1.37-2.55; P < .001) and 2012 (adjusted OR, 1.93; 95% CI, 1.76-2.11; P < .001) (Figure 4, Table 5). Last, both mean LOS (5 days vs 3 days; P < .001) and mean cost of hospitalization (US $22,269 vs $15,757; P < .001) were significantly higher in patients with AKI.

Discussion

In this study, we found that the incidence of AKI among hospitalized patients increased 4-fold between 2002 and 2012. Moreover, we identified numerous patient-specific, hospital-specific, perioperative risk factors for AKI. Most important, we found that AKI was associated with a strikingly higher risk of in-hospital death, and surviving patients were more likely to experience adverse discharge. Although the adjusted mortality rate associated with AKI decreased over that decade, the attributable risk proportion remained stable.

Few studies have addressed this significant public health concern. In one recent study in Australia, Kimmel and colleagues¹⁶ identified risk factors for AKI but lacked data on AKI outcomes. In a study of complications and mortality occurring after orthopedic surgery, Belmont and colleagues²² categorized complications as either local or systemic but did not examine renal complications. Only 2 other major studies have been conducted on renal outcomes associated with major joint surgery, and both were limited to patients with acute hip fractures. The first included acute fracture surgery patients and omitted elective joint surgery patients, and it evaluated admission renal function but not postoperative AKI.²² The second study had a sample size of only 170 patients.²³ Thus, the literature leaves us with a crucial knowledge gap in renal outcomes and their postoperative impact in elective arthroplasties.

The present study filled this information gap by examining the incidence, risk factors, outcomes, and temporal trends of AKI after elective hip and knee arthroplasties. The increasing incidence of AKI in this surgical setting is similar to that of AKI in other surgical settings (cardiac and noncardiac).²¹ Although our analysis was limited by lack of perioperative management data, patients undergoing elective joint arthroplasty can experience kidney dysfunction for several reasons, including volume depletion, postoperative sepsis, and influence of medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), especially in older patients with more comorbidities and a higher burden of CKD. Each of these factors can cause renal dysfunction in patients having orthopedic procedures.²⁴ Moreover, NSAID use among elective joint arthroplasty patients is likely higher because of an emphasis on multimodal analgesia, as recent randomized controlled trials have demonstrated the efficacy of NSAID use in controlling pain without increasing bleeding.^25-27 Our results also demonstrated that the absolute incidence of AKI after orthopedic surgery is relatively low. One possible explanation for this phenomenon is that the definitions used were based on ICD-9-CM codes that underestimate the true incidence of AKI.

Consistent with other studies, we found that certain key preoperative comorbid conditions and postoperative events were associated with higher AKI risk. We stratified the rate of AKI associated with each postoperative event (sepsis, acute MI, cardiac catheterization, need for transfusion) by DM/CKD comorbidity. CKD was associated with significantly higher AKI risk across all postoperative complications. This information may provide clinicians with bedside information that can be used to determine which patients may be at higher or lower risk for AKI.

Our analysis of patient outcomes revealed that, though AKI was relatively uncommon, it increased the risk for death during hospitalization more than 10-fold between 2002 and 2012. Although the adjusted OR of in-hospital mortality decreased over the decade studied, the concurrent increase in AKI incidence caused the attributable risk of death associated with AKI to essentially remain the same. This observation is consistent with recent reports from cardiac surgery settings.²¹ These data together suggest that ameliorating occurrences of AKI would decrease mortality and increase quality of care for patients undergoing elective joint surgeries.

We also examined the effect of AKI on resource use by studying LOS, costs, and risk for adverse discharge. Much as in other surgical settings, AKI increased both LOS and overall hospitalization costs. More important, AKI was associated with increased adverse discharge (discharge to long-term care or nursing homes). Although exact reasons are unclear, we can speculate that postoperative renal dysfunction precludes early rehabilitation, impeding desired functional outcome and disposition.^28,29 Given the projected increases in primary and revision hip and knee arthroplasties,⁵ these data predict that the impact of AKI on health outcomes will increase alarmingly in coming years.

There are limitations to our study. First, it was based on administrative data and lacked patient-level and laboratory data. As reported, the sensitivity of AKI codes remains moderate,³⁰ so the true burden may be higher than indicated here. As the definition of AKI was based on administrative coding, we also could not estimate severity, though previous studies have found that administrative codes typically capture a more severe form of disease.³¹ Another limitation is that, because the data were deidentified, we could not delineate the risk for recurrent AKI in repeated surgical procedures, though this cohort unlikely was large enough to qualitatively affect our results. The third limitation is that, though we used CCI to adjust for the comorbidity burden, we were unable to account for other unmeasured confounders associated with increased AKI incidence, such as specific medication use. In addition, given the lack of patient-level data, we could not analyze the specific factors responsible for AKI in the perioperative period. Nevertheless, the strengths of a nationally representative sample, such as large sample size and generalizability, outweigh these limitations.

Conclusion

AKI is potentially an important quality indicator of elective joint surgery, and reducing its incidence is therefore essential for quality improvement. Given that hip and knee arthroplasties are projected to increase exponentially, as is the burden of comorbid conditions in this population, postoperative AKI will continue to have an incremental impact on health and health care resources. Thus, a carefully planned approach of interdisciplinary perioperative care is warranted to reduce both the risk and the consequences of this devastating condition.

Musculoskeletal disorders, the leading cause of disability in the United States,¹ account for more than half of all persons reporting missing a workday because of a medical condition.² Shoulder disorders in particular play a significant role in the burden of musculoskeletal disorders and cost of care. In 2008, 18.9 million adults (8.2% of the US adult population) reported chronic shoulder pain.¹ Among shoulder disorders, rotator cuff pathology is the most common cause of shoulder-related disability found by orthopedic surgeons.³ Rotator cuff surgery (RCS) is one of the most commonly performed orthopedic surgical procedures, and surgery volume is on the rise. One study found a 141% increase in rotator cuff repairs between the years 1996 (~41 per 100,000 population) and 2006 (~98 per 100,000 population).⁴

US health care costs are also increasing. In 2011, $2.7 trillion was spent on health care, representing 17.9% of the national gross domestic product (GDP). According to projections, costs will rise to $4.6 trillion by 2020.5 In particular, as patients continue to live longer and remain more active into their later years, the costs of treating and managing musculoskeletal disorders become more important from a public policy standpoint. In 2006, the cost of treating musculoskeletal disorders alone was $576 billion, representing 4.5% of that year’s GDP.²

Paramount in this era of rising costs is the idea of maximizing the value of health care dollars. Health care economists Porter and Teisberg⁶ defined value as patient health outcomes achieved per dollar of cost expended in a care cycle (diagnosis, treatment, ongoing management) for a particular disease or disorder. For proper management of value, outcomes and costs for an entire cycle of care must be determined. From a practical standpoint, this first requires determining the true cost of a care cycle—dollars spent on personnel, equipment, materials, and other resources required to deliver a particular service—rather than the amount charged or reimbursed for providing the service in question.⁷

Kaplan and Anderson^8,9 described the TDABC (time-driven activity-based costing) algorithm for calculating the cost of delivering a service based on 2 parameters: unit cost of a particular resource, and time required to supply it. These parameters apply to material costs and labor costs. In the medical setting, the TDABC algorithm can be applied by defining a care delivery value chain for each aspect of patient care and then multiplying incremental cost per unit time by time required to deliver that resource (Figure 1). Tabulating the overall unit cost for each resource then yields the overall cost of the care cycle. Clinical outcomes data can then be determined and used to calculate overall value for the patient care cycle.

In the study reported here, we used the TDABC algorithm to calculate the direct financial costs of surgical treatment of rotator cuff tears confirmed by magnetic resonance imaging (MRI) in an academic medical center.

Methods

Per our institution’s Office for the Protection of Research Subjects, institutional review board (IRB) approval is required only for projects using “human subjects” as defined by federal policy. In the present study, no private information could be identified, and all data were obtained from hospital billing records without intervention or interaction with individual patients. Accordingly, IRB approval was deemed unnecessary for our economic cost analysis.

Billing records of a single academic fellowship-trained sports surgeon were reviewed to identify patients who underwent primary repair of an MRI-confirmed rotator cuff tear between April 1, 2009, and July 31, 2012. Patients who had undergone prior shoulder surgery of any type were excluded from the study. Operative reports were reviewed, and exact surgical procedures performed were noted. The operating surgeon selected the specific repair techniques, including single- or double-row repair, with emphasis on restoring footprint coverage and avoiding overtensioning.

All surgeries were performed in an outpatient surgical center owned and operated by the surgeon’s home university. Surgeries were performed by the attending physician assisted by a senior orthopedic resident. The RCS care cycle was divided into 3 phases (Figure 2):

1. Preoperative. Patient’s interaction with receptionist in surgery center, time with preoperative nurse and circulating nurse in preoperative area, resident check-in time, and time placing preoperative nerve block and consumable materials used during block placement.

2. Operative. Time in operating room with surgical team for RCS, consumable materials used during surgery (eg, anchors, shavers, drapes), anesthetic medications, shoulder abduction pillow placed on completion of surgery, and cost of instrument processing.

3. Postoperative. Time in postoperative recovery area with recovery room nursing staff.

Time in each portion of the care cycle was directly observed and tabulated by hospital volunteers in the surgery center. Institutional billing data were used to identify material resources consumed, and the actual cost paid by the hospital for these resources was obtained from internal records. Mean hourly salary data and standard benefit rates were obtained for surgery center staff. Attending physician salary was extrapolated from published mean market salary data for academic physicians and mean hours worked,^10,11 and resident physician costs were tabulated from publically available institutional payroll data and average resident work hours at our institution. These cost data and times were then used to tabulate total cost for the RCS care cycle using the TDABC algorithm.

Results

We identified 28 shoulders in 26 patients (mean age, 54.5 years) who met the inclusion criteria. Of these 28 shoulders, 18 (64.3%) had an isolated supraspinatus tear, 8 (28.6%) had combined supraspinatus and infraspinatus tears, 1 (3.6%) had combined supraspinatus and subscapularis tears, and 1 (3.6%) had an isolated infraspinatus tear. Demographic data are listed in Table 1.

All patients received an interscalene nerve block in the preoperative area before being brought into the operating room. In our analysis, we included nerve block supply costs and the anesthesiologist’s mean time placing the nerve block.

In all cases, primary rotator cuff repair was performed with suture anchors (Parcus Medical) with the patient in the lateral decubitus position. In 13 (46%) of the 28 shoulders, this repair was described as “complex,” requiring double-row technique. Subacromial decompression and bursectomy were performed in addition to the rotator cuff repair. Labral débridement was performed in 23 patients, synovectomy in 10, biceps tenodesis with anchor (Smith & Nephew) in 1, and biceps tenotomy in 1. Mean time in operating room was 148 minutes; mean time in postoperative recovery unit was 105 minutes.

Directly observing the care cycle, hospital volunteers found that patients spent a mean of 15 minutes with the receptionist when they arrived in the outpatient surgical center, 25 minutes with nurses for check-in in the preoperative holding area, and 10 minutes with the anesthesiology resident and 15 minutes with the orthopedic surgery resident for preoperative evaluation and paperwork. Mean nerve block time was 20 minutes. Mean electrocardiogram (ECG) time (12 patients) was 15 minutes. The surgical technician spent a mean time of 20 minutes setting up the operating room before the patient was brought in and 15 minutes cleaning up after the patient was transferred to the recovery room. Costs of postoperative care in the recovery room were based on a 2:1 patient-to-nurse ratio, as is the standard practice in our outpatient surgery center.

Using the times mentioned and our hospital’s salary data—including standard hospital benefits rates of 33.5% for nonphysicians and 17.65% for physicians—we determined, using the TDABC algorithm, a direct cost of $5904.21 for this process cycle, excluding hospital overhead and indirect costs. Table 2 provides the overall cost breakdown. Compared with the direct economic cost, the mean hospital charge to insurers for the procedure was $31,459.35. Mean reimbursement from insurers was $9679.08.

Overall attending and resident physician costs were $1077.75, which consisted of $623.66 for the surgeon and $454.09 for the anesthesiologist (included placement of nerve block and administration of anesthesia during surgery). Preoperative bloodwork was obtained in 23 cases, adding a mean cost of $111.04 after adjusting for standard hospital markup. Preoperative ECG was performed in 12 cases, for an added mean cost of $7.30 based on the TDABC algorithm.

We also broke down costs by care cycle phase. The preoperative phase, excluding the preoperative laboratory studies and ECGs (not performed in all cases), cost $134.34 (2.3% of total costs); the operative phase cost $5718.01 (96.8% of total costs); and the postoperative phase cost $51.86 (0.9% of total costs). Within the operative phase, the cost of consumables (specifically, suture anchors) was the main cost driver. Mean anchor cost per case was $3432.67. “Complex” tears involving a double-row repair averaged $4570.25 in anchor cost per patient, as compared with $2522.60 in anchor costs for simple repairs.

Discussion

US health care costs continue to increase unsustainably, with rising pressure on hospitals and providers to deliver the highest value for each health care dollar. The present study is the first to calculate (using the TDABC algorithm) the direct economic cost ($5904.21) of the entire RCS care cycle at a university-based outpatient surgery center. Rent, utility costs, administrative costs, overhead, and other indirect costs at the surgery center were not included in this cost analysis, as they would be incurred irrespective of type of surgery performed. As such, our data isolate the procedure-specific costs of rotator cuff repair in order to provide a more meaningful comparison for other institutions, where indirect costs may be different.

In the literature, rigorous economic analysis of shoulder pathology is sparse. Kuye and colleagues¹² systematically reviewed economic evaluations in shoulder surgery for the period 1980–2010 and noted more than 50% of the papers were published between 2005 and 2010.¹² They also noted the poor quality of these studies and concluded more rigorous economic evaluations are needed to help justify the rising costs of shoulder-related treatments.

Several studies have directly evaluated costs associated with RCS. Cordasco and colleagues¹³ detailed the success of open rotator cuff repair as an outpatient procedure—noting its 43% cost savings ($4300 for outpatient vs $7500 for inpatient) and high patient satisfaction—using hospital charge data for operating room time, supplies, instruments, and postoperative slings. Churchill and Ghorai¹⁴ evaluated costs of mini-open and arthroscopic rotator cuff repairs in a statewide database and estimated the arthroscopic repair cost at $8985, compared with $7841 for the mini-open repair. They used reported hospital charge data, which were not itemized and did not include physician professional fees. Adla and colleagues,¹⁵ in a similar analysis of open versus arthroscopic cuff repair, estimated direct material costs of $1609.50 (arthroscopic) and $360.75 (open); these figures were converted from 2005 UK currency using the exchange rate cited in their paper. Salaries of surgeon, anesthesiologist, and other operating room personnel were said to be included in the operating room cost, but the authors’ paper did not include these data.

Two studies directly estimated the costs of arthroscopic rotator cuff repair. Hearnden and Tennent¹⁶ calculated the cost of RCS at their UK institution to be £2672, which included cost of operating room consumable materials, medication, and salaries of operating room personnel, including surgeon and anesthesiologist. Using online currency conversion from 2008 exchange rates and adjusting for inflation gave a corresponding US cost of $5449.63.¹⁷ Vitale and colleagues¹⁸ prospectively calculated costs of arthroscopic rotator cuff repair over a 1-year period using a cost-to-charge ratio from tabulated inpatient charges, procedure charges, and physician fees and payments abstracted from medical records, hospital billing, and administrative databases. Mean total cost for this cycle was $10,605.20, which included several costs (physical therapy, radiologist fees) not included in the present study. These studies, though more comprehensive than prior work, did not capture the entire cycle of surgical care.

Our study was designed to provide initial data on the direct costs of arthroscopic repair of the rotator cuff for the entire process cycle. Our overall cost estimate of $5904.21 differs significantly from prior work—not unexpected given the completely different cost methodology used.

Our study had several limitations. First, it was a single-surgeon evaluation, and a number of operating room variables (eg, use of adjunct instrumentation such as radiofrequency probes, differences in draping preferences) as well as surgeon volume in performing rotator cuff repairs might have substantially affected the reproducibility and generalizability of our data. Similarly, the large number of adjunctive procedures (eg, subacromial decompression, labral débridement) performed in conjunction with the rotator cuff repairs added operative time and therefore increased overall cost. Double-row repairs added operative time and increased the cost of consumable materials as well. Differences in surgeon preference for suture anchors may also be important, as anchors are a major cost driver and can vary significantly between vendors and institutions. Tear-related variables (eg, tear size, tear chronicity, degree of fatty cuff degeneration) were not controlled for and might have significantly affected operative time and associated cost. Resident involvement in the surgical procedure and anesthesia process in an academic setting prolongs surgical time and thus directly impacts costs.

In addition, we used the patient’s time in the operating room as a proxy for actual surgical time, as this was the only reliable and reproducible data point available in our electronic medical record. As such, an unquantifiable amount of surgeon time may have been overallocated to our cost estimate for time spent inducing anesthesia, positioning, helping take the patient off the operating table, and so on. However, as typical surgeon practice is to be involved in these tasks in the operating room, the possible overestimate of surgeon cost is likely minimal.

Our salary data for the TDABC algorithm were based on national averages for work hours and gross income for physicians and on hospital-based wage structure and may not be generalizable to other institutions. There may also be regional differences in work hours and salaries, which in turn would factor into a different per-minute cost for surgeon and anesthesiologist, depending on the exact geographic area where the surgery is performed. Costs may be higher at institutions that use certified nurse anesthetists rather than resident physicians because of the salary differences between these practitioners.

Moreover, the time that patients spend in the holding area—waiting to go into surgery and, after surgery, waiting for their ride home, for their prescriptions to be ready, and so forth—is an important variable to consider from a cost standpoint. However, as this time varied significantly and involved minimal contact with hospital personnel, we excluded its associated costs from our analysis. Similarly, and as already noted, hospital overhead and other indirect costs were excluded from analysis as well.

Conclusion

Using the TDABC algorithm, we found a direct economic cost of $5904.21 for RCS at our academic outpatient surgical center, with anchor cost the main cost driver. Judicious use of consumable resources is a key focus for cost containment in arthroscopic shoulder surgery, particularly with respect to implantable suture anchors. However, in the setting of more complex tears that require multiple anchors in a double-row repair construct, our pilot data may be useful to hospitals and surgery centers negotiating procedural reimbursement for the increased cost of complex repairs. Use of the TDABC algorithm for RCS and other procedures may also help in identifying opportunities to deliver more cost-effective health care.

Musculoskeletal disorders, the leading cause of disability in the United States,¹ account for more than half of all persons reporting missing a workday because of a medical condition.² Shoulder disorders in particular play a significant role in the burden of musculoskeletal disorders and cost of care. In 2008, 18.9 million adults (8.2% of the US adult population) reported chronic shoulder pain.¹ Among shoulder disorders, rotator cuff pathology is the most common cause of shoulder-related disability found by orthopedic surgeons.³ Rotator cuff surgery (RCS) is one of the most commonly performed orthopedic surgical procedures, and surgery volume is on the rise. One study found a 141% increase in rotator cuff repairs between the years 1996 (~41 per 100,000 population) and 2006 (~98 per 100,000 population).⁴

US health care costs are also increasing. In 2011, $2.7 trillion was spent on health care, representing 17.9% of the national gross domestic product (GDP). According to projections, costs will rise to $4.6 trillion by 2020.5 In particular, as patients continue to live longer and remain more active into their later years, the costs of treating and managing musculoskeletal disorders become more important from a public policy standpoint. In 2006, the cost of treating musculoskeletal disorders alone was $576 billion, representing 4.5% of that year’s GDP.²

Paramount in this era of rising costs is the idea of maximizing the value of health care dollars. Health care economists Porter and Teisberg⁶ defined value as patient health outcomes achieved per dollar of cost expended in a care cycle (diagnosis, treatment, ongoing management) for a particular disease or disorder. For proper management of value, outcomes and costs for an entire cycle of care must be determined. From a practical standpoint, this first requires determining the true cost of a care cycle—dollars spent on personnel, equipment, materials, and other resources required to deliver a particular service—rather than the amount charged or reimbursed for providing the service in question.⁷

Kaplan and Anderson^8,9 described the TDABC (time-driven activity-based costing) algorithm for calculating the cost of delivering a service based on 2 parameters: unit cost of a particular resource, and time required to supply it. These parameters apply to material costs and labor costs. In the medical setting, the TDABC algorithm can be applied by defining a care delivery value chain for each aspect of patient care and then multiplying incremental cost per unit time by time required to deliver that resource (Figure 1). Tabulating the overall unit cost for each resource then yields the overall cost of the care cycle. Clinical outcomes data can then be determined and used to calculate overall value for the patient care cycle.

In the study reported here, we used the TDABC algorithm to calculate the direct financial costs of surgical treatment of rotator cuff tears confirmed by magnetic resonance imaging (MRI) in an academic medical center.

Methods

Per our institution’s Office for the Protection of Research Subjects, institutional review board (IRB) approval is required only for projects using “human subjects” as defined by federal policy. In the present study, no private information could be identified, and all data were obtained from hospital billing records without intervention or interaction with individual patients. Accordingly, IRB approval was deemed unnecessary for our economic cost analysis.

Billing records of a single academic fellowship-trained sports surgeon were reviewed to identify patients who underwent primary repair of an MRI-confirmed rotator cuff tear between April 1, 2009, and July 31, 2012. Patients who had undergone prior shoulder surgery of any type were excluded from the study. Operative reports were reviewed, and exact surgical procedures performed were noted. The operating surgeon selected the specific repair techniques, including single- or double-row repair, with emphasis on restoring footprint coverage and avoiding overtensioning.

All surgeries were performed in an outpatient surgical center owned and operated by the surgeon’s home university. Surgeries were performed by the attending physician assisted by a senior orthopedic resident. The RCS care cycle was divided into 3 phases (Figure 2):

1. Preoperative. Patient’s interaction with receptionist in surgery center, time with preoperative nurse and circulating nurse in preoperative area, resident check-in time, and time placing preoperative nerve block and consumable materials used during block placement.

2. Operative. Time in operating room with surgical team for RCS, consumable materials used during surgery (eg, anchors, shavers, drapes), anesthetic medications, shoulder abduction pillow placed on completion of surgery, and cost of instrument processing.

3. Postoperative. Time in postoperative recovery area with recovery room nursing staff.

Time in each portion of the care cycle was directly observed and tabulated by hospital volunteers in the surgery center. Institutional billing data were used to identify material resources consumed, and the actual cost paid by the hospital for these resources was obtained from internal records. Mean hourly salary data and standard benefit rates were obtained for surgery center staff. Attending physician salary was extrapolated from published mean market salary data for academic physicians and mean hours worked,^10,11 and resident physician costs were tabulated from publically available institutional payroll data and average resident work hours at our institution. These cost data and times were then used to tabulate total cost for the RCS care cycle using the TDABC algorithm.

Results

We identified 28 shoulders in 26 patients (mean age, 54.5 years) who met the inclusion criteria. Of these 28 shoulders, 18 (64.3%) had an isolated supraspinatus tear, 8 (28.6%) had combined supraspinatus and infraspinatus tears, 1 (3.6%) had combined supraspinatus and subscapularis tears, and 1 (3.6%) had an isolated infraspinatus tear. Demographic data are listed in Table 1.

All patients received an interscalene nerve block in the preoperative area before being brought into the operating room. In our analysis, we included nerve block supply costs and the anesthesiologist’s mean time placing the nerve block.

In all cases, primary rotator cuff repair was performed with suture anchors (Parcus Medical) with the patient in the lateral decubitus position. In 13 (46%) of the 28 shoulders, this repair was described as “complex,” requiring double-row technique. Subacromial decompression and bursectomy were performed in addition to the rotator cuff repair. Labral débridement was performed in 23 patients, synovectomy in 10, biceps tenodesis with anchor (Smith & Nephew) in 1, and biceps tenotomy in 1. Mean time in operating room was 148 minutes; mean time in postoperative recovery unit was 105 minutes.

Directly observing the care cycle, hospital volunteers found that patients spent a mean of 15 minutes with the receptionist when they arrived in the outpatient surgical center, 25 minutes with nurses for check-in in the preoperative holding area, and 10 minutes with the anesthesiology resident and 15 minutes with the orthopedic surgery resident for preoperative evaluation and paperwork. Mean nerve block time was 20 minutes. Mean electrocardiogram (ECG) time (12 patients) was 15 minutes. The surgical technician spent a mean time of 20 minutes setting up the operating room before the patient was brought in and 15 minutes cleaning up after the patient was transferred to the recovery room. Costs of postoperative care in the recovery room were based on a 2:1 patient-to-nurse ratio, as is the standard practice in our outpatient surgery center.

Using the times mentioned and our hospital’s salary data—including standard hospital benefits rates of 33.5% for nonphysicians and 17.65% for physicians—we determined, using the TDABC algorithm, a direct cost of $5904.21 for this process cycle, excluding hospital overhead and indirect costs. Table 2 provides the overall cost breakdown. Compared with the direct economic cost, the mean hospital charge to insurers for the procedure was $31,459.35. Mean reimbursement from insurers was $9679.08.

Overall attending and resident physician costs were $1077.75, which consisted of $623.66 for the surgeon and $454.09 for the anesthesiologist (included placement of nerve block and administration of anesthesia during surgery). Preoperative bloodwork was obtained in 23 cases, adding a mean cost of $111.04 after adjusting for standard hospital markup. Preoperative ECG was performed in 12 cases, for an added mean cost of $7.30 based on the TDABC algorithm.

We also broke down costs by care cycle phase. The preoperative phase, excluding the preoperative laboratory studies and ECGs (not performed in all cases), cost $134.34 (2.3% of total costs); the operative phase cost $5718.01 (96.8% of total costs); and the postoperative phase cost $51.86 (0.9% of total costs). Within the operative phase, the cost of consumables (specifically, suture anchors) was the main cost driver. Mean anchor cost per case was $3432.67. “Complex” tears involving a double-row repair averaged $4570.25 in anchor cost per patient, as compared with $2522.60 in anchor costs for simple repairs.

Discussion

US health care costs continue to increase unsustainably, with rising pressure on hospitals and providers to deliver the highest value for each health care dollar. The present study is the first to calculate (using the TDABC algorithm) the direct economic cost ($5904.21) of the entire RCS care cycle at a university-based outpatient surgery center. Rent, utility costs, administrative costs, overhead, and other indirect costs at the surgery center were not included in this cost analysis, as they would be incurred irrespective of type of surgery performed. As such, our data isolate the procedure-specific costs of rotator cuff repair in order to provide a more meaningful comparison for other institutions, where indirect costs may be different.

In the literature, rigorous economic analysis of shoulder pathology is sparse. Kuye and colleagues¹² systematically reviewed economic evaluations in shoulder surgery for the period 1980–2010 and noted more than 50% of the papers were published between 2005 and 2010.¹² They also noted the poor quality of these studies and concluded more rigorous economic evaluations are needed to help justify the rising costs of shoulder-related treatments.

Several studies have directly evaluated costs associated with RCS. Cordasco and colleagues¹³ detailed the success of open rotator cuff repair as an outpatient procedure—noting its 43% cost savings ($4300 for outpatient vs $7500 for inpatient) and high patient satisfaction—using hospital charge data for operating room time, supplies, instruments, and postoperative slings. Churchill and Ghorai¹⁴ evaluated costs of mini-open and arthroscopic rotator cuff repairs in a statewide database and estimated the arthroscopic repair cost at $8985, compared with $7841 for the mini-open repair. They used reported hospital charge data, which were not itemized and did not include physician professional fees. Adla and colleagues,¹⁵ in a similar analysis of open versus arthroscopic cuff repair, estimated direct material costs of $1609.50 (arthroscopic) and $360.75 (open); these figures were converted from 2005 UK currency using the exchange rate cited in their paper. Salaries of surgeon, anesthesiologist, and other operating room personnel were said to be included in the operating room cost, but the authors’ paper did not include these data.

Two studies directly estimated the costs of arthroscopic rotator cuff repair. Hearnden and Tennent¹⁶ calculated the cost of RCS at their UK institution to be £2672, which included cost of operating room consumable materials, medication, and salaries of operating room personnel, including surgeon and anesthesiologist. Using online currency conversion from 2008 exchange rates and adjusting for inflation gave a corresponding US cost of $5449.63.¹⁷ Vitale and colleagues¹⁸ prospectively calculated costs of arthroscopic rotator cuff repair over a 1-year period using a cost-to-charge ratio from tabulated inpatient charges, procedure charges, and physician fees and payments abstracted from medical records, hospital billing, and administrative databases. Mean total cost for this cycle was $10,605.20, which included several costs (physical therapy, radiologist fees) not included in the present study. These studies, though more comprehensive than prior work, did not capture the entire cycle of surgical care.

Our study was designed to provide initial data on the direct costs of arthroscopic repair of the rotator cuff for the entire process cycle. Our overall cost estimate of $5904.21 differs significantly from prior work—not unexpected given the completely different cost methodology used.

Our study had several limitations. First, it was a single-surgeon evaluation, and a number of operating room variables (eg, use of adjunct instrumentation such as radiofrequency probes, differences in draping preferences) as well as surgeon volume in performing rotator cuff repairs might have substantially affected the reproducibility and generalizability of our data. Similarly, the large number of adjunctive procedures (eg, subacromial decompression, labral débridement) performed in conjunction with the rotator cuff repairs added operative time and therefore increased overall cost. Double-row repairs added operative time and increased the cost of consumable materials as well. Differences in surgeon preference for suture anchors may also be important, as anchors are a major cost driver and can vary significantly between vendors and institutions. Tear-related variables (eg, tear size, tear chronicity, degree of fatty cuff degeneration) were not controlled for and might have significantly affected operative time and associated cost. Resident involvement in the surgical procedure and anesthesia process in an academic setting prolongs surgical time and thus directly impacts costs.

In addition, we used the patient’s time in the operating room as a proxy for actual surgical time, as this was the only reliable and reproducible data point available in our electronic medical record. As such, an unquantifiable amount of surgeon time may have been overallocated to our cost estimate for time spent inducing anesthesia, positioning, helping take the patient off the operating table, and so on. However, as typical surgeon practice is to be involved in these tasks in the operating room, the possible overestimate of surgeon cost is likely minimal.

Our salary data for the TDABC algorithm were based on national averages for work hours and gross income for physicians and on hospital-based wage structure and may not be generalizable to other institutions. There may also be regional differences in work hours and salaries, which in turn would factor into a different per-minute cost for surgeon and anesthesiologist, depending on the exact geographic area where the surgery is performed. Costs may be higher at institutions that use certified nurse anesthetists rather than resident physicians because of the salary differences between these practitioners.

Moreover, the time that patients spend in the holding area—waiting to go into surgery and, after surgery, waiting for their ride home, for their prescriptions to be ready, and so forth—is an important variable to consider from a cost standpoint. However, as this time varied significantly and involved minimal contact with hospital personnel, we excluded its associated costs from our analysis. Similarly, and as already noted, hospital overhead and other indirect costs were excluded from analysis as well.

Conclusion

Using the TDABC algorithm, we found a direct economic cost of $5904.21 for RCS at our academic outpatient surgical center, with anchor cost the main cost driver. Judicious use of consumable resources is a key focus for cost containment in arthroscopic shoulder surgery, particularly with respect to implantable suture anchors. However, in the setting of more complex tears that require multiple anchors in a double-row repair construct, our pilot data may be useful to hospitals and surgery centers negotiating procedural reimbursement for the increased cost of complex repairs. Use of the TDABC algorithm for RCS and other procedures may also help in identifying opportunities to deliver more cost-effective health care.

Musculoskeletal disorders, the leading cause of disability in the United States,¹ account for more than half of all persons reporting missing a workday because of a medical condition.² Shoulder disorders in particular play a significant role in the burden of musculoskeletal disorders and cost of care. In 2008, 18.9 million adults (8.2% of the US adult population) reported chronic shoulder pain.¹ Among shoulder disorders, rotator cuff pathology is the most common cause of shoulder-related disability found by orthopedic surgeons.³ Rotator cuff surgery (RCS) is one of the most commonly performed orthopedic surgical procedures, and surgery volume is on the rise. One study found a 141% increase in rotator cuff repairs between the years 1996 (~41 per 100,000 population) and 2006 (~98 per 100,000 population).⁴

US health care costs are also increasing. In 2011, $2.7 trillion was spent on health care, representing 17.9% of the national gross domestic product (GDP). According to projections, costs will rise to $4.6 trillion by 2020.5 In particular, as patients continue to live longer and remain more active into their later years, the costs of treating and managing musculoskeletal disorders become more important from a public policy standpoint. In 2006, the cost of treating musculoskeletal disorders alone was $576 billion, representing 4.5% of that year’s GDP.²

Paramount in this era of rising costs is the idea of maximizing the value of health care dollars. Health care economists Porter and Teisberg⁶ defined value as patient health outcomes achieved per dollar of cost expended in a care cycle (diagnosis, treatment, ongoing management) for a particular disease or disorder. For proper management of value, outcomes and costs for an entire cycle of care must be determined. From a practical standpoint, this first requires determining the true cost of a care cycle—dollars spent on personnel, equipment, materials, and other resources required to deliver a particular service—rather than the amount charged or reimbursed for providing the service in question.⁷

Kaplan and Anderson^8,9 described the TDABC (time-driven activity-based costing) algorithm for calculating the cost of delivering a service based on 2 parameters: unit cost of a particular resource, and time required to supply it. These parameters apply to material costs and labor costs. In the medical setting, the TDABC algorithm can be applied by defining a care delivery value chain for each aspect of patient care and then multiplying incremental cost per unit time by time required to deliver that resource (Figure 1). Tabulating the overall unit cost for each resource then yields the overall cost of the care cycle. Clinical outcomes data can then be determined and used to calculate overall value for the patient care cycle.

In the study reported here, we used the TDABC algorithm to calculate the direct financial costs of surgical treatment of rotator cuff tears confirmed by magnetic resonance imaging (MRI) in an academic medical center.

Methods

Per our institution’s Office for the Protection of Research Subjects, institutional review board (IRB) approval is required only for projects using “human subjects” as defined by federal policy. In the present study, no private information could be identified, and all data were obtained from hospital billing records without intervention or interaction with individual patients. Accordingly, IRB approval was deemed unnecessary for our economic cost analysis.

Billing records of a single academic fellowship-trained sports surgeon were reviewed to identify patients who underwent primary repair of an MRI-confirmed rotator cuff tear between April 1, 2009, and July 31, 2012. Patients who had undergone prior shoulder surgery of any type were excluded from the study. Operative reports were reviewed, and exact surgical procedures performed were noted. The operating surgeon selected the specific repair techniques, including single- or double-row repair, with emphasis on restoring footprint coverage and avoiding overtensioning.

All surgeries were performed in an outpatient surgical center owned and operated by the surgeon’s home university. Surgeries were performed by the attending physician assisted by a senior orthopedic resident. The RCS care cycle was divided into 3 phases (Figure 2):

1. Preoperative. Patient’s interaction with receptionist in surgery center, time with preoperative nurse and circulating nurse in preoperative area, resident check-in time, and time placing preoperative nerve block and consumable materials used during block placement.

2. Operative. Time in operating room with surgical team for RCS, consumable materials used during surgery (eg, anchors, shavers, drapes), anesthetic medications, shoulder abduction pillow placed on completion of surgery, and cost of instrument processing.

3. Postoperative. Time in postoperative recovery area with recovery room nursing staff.

Time in each portion of the care cycle was directly observed and tabulated by hospital volunteers in the surgery center. Institutional billing data were used to identify material resources consumed, and the actual cost paid by the hospital for these resources was obtained from internal records. Mean hourly salary data and standard benefit rates were obtained for surgery center staff. Attending physician salary was extrapolated from published mean market salary data for academic physicians and mean hours worked,^10,11 and resident physician costs were tabulated from publically available institutional payroll data and average resident work hours at our institution. These cost data and times were then used to tabulate total cost for the RCS care cycle using the TDABC algorithm.

Results

We identified 28 shoulders in 26 patients (mean age, 54.5 years) who met the inclusion criteria. Of these 28 shoulders, 18 (64.3%) had an isolated supraspinatus tear, 8 (28.6%) had combined supraspinatus and infraspinatus tears, 1 (3.6%) had combined supraspinatus and subscapularis tears, and 1 (3.6%) had an isolated infraspinatus tear. Demographic data are listed in Table 1.

All patients received an interscalene nerve block in the preoperative area before being brought into the operating room. In our analysis, we included nerve block supply costs and the anesthesiologist’s mean time placing the nerve block.

In all cases, primary rotator cuff repair was performed with suture anchors (Parcus Medical) with the patient in the lateral decubitus position. In 13 (46%) of the 28 shoulders, this repair was described as “complex,” requiring double-row technique. Subacromial decompression and bursectomy were performed in addition to the rotator cuff repair. Labral débridement was performed in 23 patients, synovectomy in 10, biceps tenodesis with anchor (Smith & Nephew) in 1, and biceps tenotomy in 1. Mean time in operating room was 148 minutes; mean time in postoperative recovery unit was 105 minutes.

Directly observing the care cycle, hospital volunteers found that patients spent a mean of 15 minutes with the receptionist when they arrived in the outpatient surgical center, 25 minutes with nurses for check-in in the preoperative holding area, and 10 minutes with the anesthesiology resident and 15 minutes with the orthopedic surgery resident for preoperative evaluation and paperwork. Mean nerve block time was 20 minutes. Mean electrocardiogram (ECG) time (12 patients) was 15 minutes. The surgical technician spent a mean time of 20 minutes setting up the operating room before the patient was brought in and 15 minutes cleaning up after the patient was transferred to the recovery room. Costs of postoperative care in the recovery room were based on a 2:1 patient-to-nurse ratio, as is the standard practice in our outpatient surgery center.

Using the times mentioned and our hospital’s salary data—including standard hospital benefits rates of 33.5% for nonphysicians and 17.65% for physicians—we determined, using the TDABC algorithm, a direct cost of $5904.21 for this process cycle, excluding hospital overhead and indirect costs. Table 2 provides the overall cost breakdown. Compared with the direct economic cost, the mean hospital charge to insurers for the procedure was $31,459.35. Mean reimbursement from insurers was $9679.08.

Overall attending and resident physician costs were $1077.75, which consisted of $623.66 for the surgeon and $454.09 for the anesthesiologist (included placement of nerve block and administration of anesthesia during surgery). Preoperative bloodwork was obtained in 23 cases, adding a mean cost of $111.04 after adjusting for standard hospital markup. Preoperative ECG was performed in 12 cases, for an added mean cost of $7.30 based on the TDABC algorithm.

We also broke down costs by care cycle phase. The preoperative phase, excluding the preoperative laboratory studies and ECGs (not performed in all cases), cost $134.34 (2.3% of total costs); the operative phase cost $5718.01 (96.8% of total costs); and the postoperative phase cost $51.86 (0.9% of total costs). Within the operative phase, the cost of consumables (specifically, suture anchors) was the main cost driver. Mean anchor cost per case was $3432.67. “Complex” tears involving a double-row repair averaged $4570.25 in anchor cost per patient, as compared with $2522.60 in anchor costs for simple repairs.

Discussion

US health care costs continue to increase unsustainably, with rising pressure on hospitals and providers to deliver the highest value for each health care dollar. The present study is the first to calculate (using the TDABC algorithm) the direct economic cost ($5904.21) of the entire RCS care cycle at a university-based outpatient surgery center. Rent, utility costs, administrative costs, overhead, and other indirect costs at the surgery center were not included in this cost analysis, as they would be incurred irrespective of type of surgery performed. As such, our data isolate the procedure-specific costs of rotator cuff repair in order to provide a more meaningful comparison for other institutions, where indirect costs may be different.

In the literature, rigorous economic analysis of shoulder pathology is sparse. Kuye and colleagues¹² systematically reviewed economic evaluations in shoulder surgery for the period 1980–2010 and noted more than 50% of the papers were published between 2005 and 2010.¹² They also noted the poor quality of these studies and concluded more rigorous economic evaluations are needed to help justify the rising costs of shoulder-related treatments.

Several studies have directly evaluated costs associated with RCS. Cordasco and colleagues¹³ detailed the success of open rotator cuff repair as an outpatient procedure—noting its 43% cost savings ($4300 for outpatient vs $7500 for inpatient) and high patient satisfaction—using hospital charge data for operating room time, supplies, instruments, and postoperative slings. Churchill and Ghorai¹⁴ evaluated costs of mini-open and arthroscopic rotator cuff repairs in a statewide database and estimated the arthroscopic repair cost at $8985, compared with $7841 for the mini-open repair. They used reported hospital charge data, which were not itemized and did not include physician professional fees. Adla and colleagues,¹⁵ in a similar analysis of open versus arthroscopic cuff repair, estimated direct material costs of $1609.50 (arthroscopic) and $360.75 (open); these figures were converted from 2005 UK currency using the exchange rate cited in their paper. Salaries of surgeon, anesthesiologist, and other operating room personnel were said to be included in the operating room cost, but the authors’ paper did not include these data.

Two studies directly estimated the costs of arthroscopic rotator cuff repair. Hearnden and Tennent¹⁶ calculated the cost of RCS at their UK institution to be £2672, which included cost of operating room consumable materials, medication, and salaries of operating room personnel, including surgeon and anesthesiologist. Using online currency conversion from 2008 exchange rates and adjusting for inflation gave a corresponding US cost of $5449.63.¹⁷ Vitale and colleagues¹⁸ prospectively calculated costs of arthroscopic rotator cuff repair over a 1-year period using a cost-to-charge ratio from tabulated inpatient charges, procedure charges, and physician fees and payments abstracted from medical records, hospital billing, and administrative databases. Mean total cost for this cycle was $10,605.20, which included several costs (physical therapy, radiologist fees) not included in the present study. These studies, though more comprehensive than prior work, did not capture the entire cycle of surgical care.

Our study was designed to provide initial data on the direct costs of arthroscopic repair of the rotator cuff for the entire process cycle. Our overall cost estimate of $5904.21 differs significantly from prior work—not unexpected given the completely different cost methodology used.

Our study had several limitations. First, it was a single-surgeon evaluation, and a number of operating room variables (eg, use of adjunct instrumentation such as radiofrequency probes, differences in draping preferences) as well as surgeon volume in performing rotator cuff repairs might have substantially affected the reproducibility and generalizability of our data. Similarly, the large number of adjunctive procedures (eg, subacromial decompression, labral débridement) performed in conjunction with the rotator cuff repairs added operative time and therefore increased overall cost. Double-row repairs added operative time and increased the cost of consumable materials as well. Differences in surgeon preference for suture anchors may also be important, as anchors are a major cost driver and can vary significantly between vendors and institutions. Tear-related variables (eg, tear size, tear chronicity, degree of fatty cuff degeneration) were not controlled for and might have significantly affected operative time and associated cost. Resident involvement in the surgical procedure and anesthesia process in an academic setting prolongs surgical time and thus directly impacts costs.

In addition, we used the patient’s time in the operating room as a proxy for actual surgical time, as this was the only reliable and reproducible data point available in our electronic medical record. As such, an unquantifiable amount of surgeon time may have been overallocated to our cost estimate for time spent inducing anesthesia, positioning, helping take the patient off the operating table, and so on. However, as typical surgeon practice is to be involved in these tasks in the operating room, the possible overestimate of surgeon cost is likely minimal.

Our salary data for the TDABC algorithm were based on national averages for work hours and gross income for physicians and on hospital-based wage structure and may not be generalizable to other institutions. There may also be regional differences in work hours and salaries, which in turn would factor into a different per-minute cost for surgeon and anesthesiologist, depending on the exact geographic area where the surgery is performed. Costs may be higher at institutions that use certified nurse anesthetists rather than resident physicians because of the salary differences between these practitioners.

Moreover, the time that patients spend in the holding area—waiting to go into surgery and, after surgery, waiting for their ride home, for their prescriptions to be ready, and so forth—is an important variable to consider from a cost standpoint. However, as this time varied significantly and involved minimal contact with hospital personnel, we excluded its associated costs from our analysis. Similarly, and as already noted, hospital overhead and other indirect costs were excluded from analysis as well.

Conclusion

Using the TDABC algorithm, we found a direct economic cost of $5904.21 for RCS at our academic outpatient surgical center, with anchor cost the main cost driver. Judicious use of consumable resources is a key focus for cost containment in arthroscopic shoulder surgery, particularly with respect to implantable suture anchors. However, in the setting of more complex tears that require multiple anchors in a double-row repair construct, our pilot data may be useful to hospitals and surgery centers negotiating procedural reimbursement for the increased cost of complex repairs. Use of the TDABC algorithm for RCS and other procedures may also help in identifying opportunities to deliver more cost-effective health care.

SAN DIEGO – When necessary, long fusions that extend from the C-spine to the pelvis can result in health-related quality of life improvements, results from a multicenter study suggest.

“Patients with spinal deformities will sometimes require long fusion constructs that extend into the cervical spine,” lead study author Dr. Han-Jo Kim said at the annual meeting of the Cervical Spine Research Society. “The prevalence of these cases is increasing, especially as revision surgery for conditions such as proximal junctional kyphosis increase. They are also indicated for other diagnoses, such a progressive cervical deformity, cervical myelopathy as well as neuromuscular disorders.”

Prior investigations that have examined outcomes for these long constructs usually focus on patients who have had fusions from the upper thoracic spine to the pelvis, added Dr. Kim, an orthopedic spine surgeon at the Hospital for Special Surgery, New York. “To my knowledge, there are no studies in the literature that report on the subset of patients who have had fusions from the cervical spine to the pelvis,” he said. “The question is, even though these revisions may be necessary, does surgical intervention result in improved outcomes for these patients despite the extent of these long fusions?”

In an effort to determine the outcomes and rates of complications in patients who had fusions from the cervical spine to the pelvis, Dr. Kim and his associates conducted a retrospective review of patients who underwent fusions from the cervical spine to the pelvis at four institutions during 2003-2014. The researchers administered outcome scores utilizing the Scoliosis Research Society 22 (SRS-22r) questionnaire; the Oswestry Disability Index (ODI); and the Neck Disability Index (NDI); and collected demographic data including age, body mass index, and follow-up time; medical history including comorbidity data, operative details, radiographic and articular outcomes data; and postoperative complications.

Of 55 patients initially included in the study, complete data were available for 46 (84%). Their average age was 42 years, nearly one-third (30%) were classified as ASA III, 4.2% were smokers, and the average follow-up time was 2.7 years. “The majority of these cases were revision operations, and osteotomies were performed in close to 60% of these patients,” Dr. Kim said. “The average operating time was over 300 minutes, and there was an average of over 2 L of blood loss for these cases.”

The researchers observed improvements in the activity, pain, and mental health domains of the SRS, as well as an improvement in the SRS total score, which improved from an average of 3.0 preoperatively to 3.5 postoperatively (P less than .01). This was greater than the minimally clinically important difference for the SRS-22r. “At least one [minimally clinically important difference] was met in all of the SRS domains, as well as in the NDI,” Dr. Kim said. “There was no change in the ODI, as we would expect for this patient subset.”

Radiographic outcomes improved significantly, he continued, with an average 31-degree correction in maximum kyphosis and a 3.3-cm improvement in sagittal vertical axis. The overall rate of complications was 71%, with major complications comprising about 39% of these cases. Medical complications were high as well (a rate of 61%), as was the rate of surgical complications (43%). More than half of the patients (54%) required reoperation during the follow-up period, and the rate of pseudarthrosis was 29%.

“These results demonstrate improved outcomes following cervical to pelvic fusions, despite the magnitude of their operations and extent of fusion,” Dr. Kim concluded. “In addition, despite the high rate of complications and reoperations, we noted a significant improvement in radiographic and clinical outcomes.”

Dr. Kim disclosed that he is a consultant for Zimmer Biomet and K2M.

[email protected]

SAN DIEGO – When necessary, long fusions that extend from the C-spine to the pelvis can result in health-related quality of life improvements, results from a multicenter study suggest.

“Patients with spinal deformities will sometimes require long fusion constructs that extend into the cervical spine,” lead study author Dr. Han-Jo Kim said at the annual meeting of the Cervical Spine Research Society. “The prevalence of these cases is increasing, especially as revision surgery for conditions such as proximal junctional kyphosis increase. They are also indicated for other diagnoses, such a progressive cervical deformity, cervical myelopathy as well as neuromuscular disorders.”

Prior investigations that have examined outcomes for these long constructs usually focus on patients who have had fusions from the upper thoracic spine to the pelvis, added Dr. Kim, an orthopedic spine surgeon at the Hospital for Special Surgery, New York. “To my knowledge, there are no studies in the literature that report on the subset of patients who have had fusions from the cervical spine to the pelvis,” he said. “The question is, even though these revisions may be necessary, does surgical intervention result in improved outcomes for these patients despite the extent of these long fusions?”

In an effort to determine the outcomes and rates of complications in patients who had fusions from the cervical spine to the pelvis, Dr. Kim and his associates conducted a retrospective review of patients who underwent fusions from the cervical spine to the pelvis at four institutions during 2003-2014. The researchers administered outcome scores utilizing the Scoliosis Research Society 22 (SRS-22r) questionnaire; the Oswestry Disability Index (ODI); and the Neck Disability Index (NDI); and collected demographic data including age, body mass index, and follow-up time; medical history including comorbidity data, operative details, radiographic and articular outcomes data; and postoperative complications.

Of 55 patients initially included in the study, complete data were available for 46 (84%). Their average age was 42 years, nearly one-third (30%) were classified as ASA III, 4.2% were smokers, and the average follow-up time was 2.7 years. “The majority of these cases were revision operations, and osteotomies were performed in close to 60% of these patients,” Dr. Kim said. “The average operating time was over 300 minutes, and there was an average of over 2 L of blood loss for these cases.”

The researchers observed improvements in the activity, pain, and mental health domains of the SRS, as well as an improvement in the SRS total score, which improved from an average of 3.0 preoperatively to 3.5 postoperatively (P less than .01). This was greater than the minimally clinically important difference for the SRS-22r. “At least one [minimally clinically important difference] was met in all of the SRS domains, as well as in the NDI,” Dr. Kim said. “There was no change in the ODI, as we would expect for this patient subset.”

Radiographic outcomes improved significantly, he continued, with an average 31-degree correction in maximum kyphosis and a 3.3-cm improvement in sagittal vertical axis. The overall rate of complications was 71%, with major complications comprising about 39% of these cases. Medical complications were high as well (a rate of 61%), as was the rate of surgical complications (43%). More than half of the patients (54%) required reoperation during the follow-up period, and the rate of pseudarthrosis was 29%.

“These results demonstrate improved outcomes following cervical to pelvic fusions, despite the magnitude of their operations and extent of fusion,” Dr. Kim concluded. “In addition, despite the high rate of complications and reoperations, we noted a significant improvement in radiographic and clinical outcomes.”

Dr. Kim disclosed that he is a consultant for Zimmer Biomet and K2M.

[email protected]

SAN DIEGO – When necessary, long fusions that extend from the C-spine to the pelvis can result in health-related quality of life improvements, results from a multicenter study suggest.

“Patients with spinal deformities will sometimes require long fusion constructs that extend into the cervical spine,” lead study author Dr. Han-Jo Kim said at the annual meeting of the Cervical Spine Research Society. “The prevalence of these cases is increasing, especially as revision surgery for conditions such as proximal junctional kyphosis increase. They are also indicated for other diagnoses, such a progressive cervical deformity, cervical myelopathy as well as neuromuscular disorders.”

Prior investigations that have examined outcomes for these long constructs usually focus on patients who have had fusions from the upper thoracic spine to the pelvis, added Dr. Kim, an orthopedic spine surgeon at the Hospital for Special Surgery, New York. “To my knowledge, there are no studies in the literature that report on the subset of patients who have had fusions from the cervical spine to the pelvis,” he said. “The question is, even though these revisions may be necessary, does surgical intervention result in improved outcomes for these patients despite the extent of these long fusions?”

In an effort to determine the outcomes and rates of complications in patients who had fusions from the cervical spine to the pelvis, Dr. Kim and his associates conducted a retrospective review of patients who underwent fusions from the cervical spine to the pelvis at four institutions during 2003-2014. The researchers administered outcome scores utilizing the Scoliosis Research Society 22 (SRS-22r) questionnaire; the Oswestry Disability Index (ODI); and the Neck Disability Index (NDI); and collected demographic data including age, body mass index, and follow-up time; medical history including comorbidity data, operative details, radiographic and articular outcomes data; and postoperative complications.

Of 55 patients initially included in the study, complete data were available for 46 (84%). Their average age was 42 years, nearly one-third (30%) were classified as ASA III, 4.2% were smokers, and the average follow-up time was 2.7 years. “The majority of these cases were revision operations, and osteotomies were performed in close to 60% of these patients,” Dr. Kim said. “The average operating time was over 300 minutes, and there was an average of over 2 L of blood loss for these cases.”

The researchers observed improvements in the activity, pain, and mental health domains of the SRS, as well as an improvement in the SRS total score, which improved from an average of 3.0 preoperatively to 3.5 postoperatively (P less than .01). This was greater than the minimally clinically important difference for the SRS-22r. “At least one [minimally clinically important difference] was met in all of the SRS domains, as well as in the NDI,” Dr. Kim said. “There was no change in the ODI, as we would expect for this patient subset.”

Radiographic outcomes improved significantly, he continued, with an average 31-degree correction in maximum kyphosis and a 3.3-cm improvement in sagittal vertical axis. The overall rate of complications was 71%, with major complications comprising about 39% of these cases. Medical complications were high as well (a rate of 61%), as was the rate of surgical complications (43%). More than half of the patients (54%) required reoperation during the follow-up period, and the rate of pseudarthrosis was 29%.

“These results demonstrate improved outcomes following cervical to pelvic fusions, despite the magnitude of their operations and extent of fusion,” Dr. Kim concluded. “In addition, despite the high rate of complications and reoperations, we noted a significant improvement in radiographic and clinical outcomes.”

Dr. Kim disclosed that he is a consultant for Zimmer Biomet and K2M.

[email protected]

Since Title IX passed in 1972, women have become exponentially more involved in competitive sports, from high school to professional levels. With more women engaging in serious athletics, the specific challenges they face have come to the forefront of sports medicine. These problems include the female athlete triad, concussions, exercise safety in pregnancy, anterior cruciate ligament (ACL) injuries, and continued sex discrimination and social injustice. Orthopedists treating female athletes should be aware of these problems, each of which is discussed in this review.

1. Female athlete triad

In 1992, the term female athlete triad was coined to describe 3 problems that often coexist in high-intensity female athletes.¹ Since then, the definition has evolved, but the problem has remained essentially the same. The modern definition incorporates menstrual abnormalities, low energy availability with or without disordered eating, and decreased bone mineral density (BMD).²

With intense exercise and weight loss comes a variety of menstrual disturbances.³ In affected athletes, the hypothalamus is underactivated, and changes in gonadotropin-releasing hormone and luteinizing hormone lead to decreased estrogen production. Research suggests abnormal menses result from having inadequate energy and insufficient caloric intake to support extensive exercise.¹ This phenomenon can occur in athletes in any sport but is most prevalent in lean-body sports, such as swimming, gymnastics, and ballet. The incidence of abnormal menses is as high as 79% in ballet dancers but only 5% in the general population.³ Menstrual abnormalities indicate hormonal abnormalities that can interfere with growth and maturation in young athletes.

Although full-blown eating disorders are uncommon among female athletes, disordered eating patterns are often found among women in competitive sports. Disordered eating can involve a spectrum of inadequate caloric intake and purging behavior, such as vomiting or laxative abuse, and has been reported in up to 25% of collegiate female athletes.⁴ Physicians must recognize these conditions and initiate counseling and treatment when appropriate. Women with disordered eating are at risk for developing electrolyte imbalances, malnutrition syndromes, and osteopenia.

Although careful evaluation and counseling are important, physicians must note that, in most cases, athletics participation may also protect against disordered eating and body image difficulties. A study of 146 college-age women found better body satisfaction among athletes than among nonathletes.⁵ Lean-sport athletes (eg, swimmers, gymnasts) were at higher risk for disordered eating and body image problems than other athletes were. Similarly, other studies have found that a majority of athletes have healthy eating habits.⁴

For poorly nourished and hormonally imbalanced female athletes, decreased BMD poses substantial risk. One study found a significant difference in BMD between athletes with amenorrhea and athletes with normal menses.⁶ In a cohort of female Navy recruits, those with amenorrhea were at 91% higher risk for stress fractures; calcium and vitamin D supplementation reduced risk by 20%.⁷ Osteopenia may be a special problem for prepubescent athletes. Girls who engage in intense exercise and have delayed menarche may have a low estrogen state, predisposing them to low BMD.³ Osteopenia and osteoporosis are difficult to reverse and can put these athletes at risk for stress fractures the rest of their lives. If unrecognized, stress fractures can end an athlete’s career.

Recommendations for dual-energy X-ray absorptiometry (DXA) include testing female athletes who have a diagnosed eating disorder, body mass index under 17.5, history of delayed menarche, oligomenorrhea, 2 prior stress fractures, or prior abnormal DXA scan. Complete testing recommendations appear in the 2014 consensus statement on the female athlete triad and return to sport.^2,8

Orthopedists performing physical examinations for sports participation can screen for the female athlete triad through thoughtful questioning about menstrual history, nutrition habits, and stress fracture symptoms. Best treatment for a diagnosed case of the triad is multidisciplinary care with strong social support. When abnormal menses are an issue, referral to a gynecologist or endocrinologist and consideration of estrogen replacement should be discussed. Some cases require a psychiatrist’s assistance in treating disordered eating. Athletic trainers, coaches, and parents should be involved over the treatment course.¹ Orthopedists must counsel women with osteopenia and osteoporosis about decreasing exercise to a safe level, improving nutritional intake, and supplementing with calcium (1200-1500 mg/d) and vitamin D (600-800 IU/d).^3,7

2. Concussions

Increasing awareness of males’ sport-related concussions, particularly of concussions that occur during National Football League practice and games, has made physicians and researchers more aware of the rate of concussion in female athletes. That rate has increased, and, according to some reports, the risk for sport-related injury is higher for female athletes.⁹ A study of high school athletes found that the rate of concussion in girl’s soccer was second only to that in football.¹⁰

Concussions are categorized as mild traumatic brain injuries, and manifestations of the diagnosis are divided into physical, emotional, cognitive, and observed symptoms. The spectrum of symptoms is wide, ranging from difficulty concentrating and thinking clearly to headaches and dizziness.¹¹ Compared with male athletes who sustain a concussion, female athletes report more of these concussive symptoms and have worse visual memory scores.¹²

Efforts to change sports at the player level have been resisted. Helmets have been proposed for field hockey and lacrosse but have not passed stringent concussion testing. In soccer, which has a high rate of concussion, a reform to eliminate heading the ball has been considered. Resistance to these suggestions stems from the thought that changes could alter the traditions of the games. Some individuals have indicated that helmets may give players a false sense of security and thereby cause them to play more aggressively.

Orthopedic surgeons must be aware of concussion symptoms. Multiple concussions may have a cumulative effect on functional ability and emotional well-being and may lead to chronic traumatic encephalopathy.¹³ Concern about the long-term effects of concussion has led to the implementation of universal “return to play” laws. These laws vary by state but have 3 steps in common: Educate coaches, players, and athletes; remove athletes from play; and obtain health care professionals’ permission to return to play.¹⁴ These guidelines set up an action plan for treating an athlete who has sustained a concussion.

Encouraging results of educating coaches have been noted. Coaches who were given Centers for Disease Control and Prevention–sponsored material on preventing, recognizing, and responding to concussions were able to effectively address concussions; 6 months later, 63% were better able to appreciate the severity of concussions.¹⁵ Continued education of athletic communities should help bring this injury to the attention of those treating female athletes.

3. Exercise safety in pregnancy

Women in sports can continue their athletic regimens during pregnancy. It is important to address challenges to the pregnant woman and to the fetus when assessing the risks of exercise.

The physiologic changes that occur during pregnancy may affect how a pregnant athlete responds to stress. Plasma volume, red blood cell volume, and cardiac function and output all increase during normal pregnancy.^3,16 Abnormal heart rate during pregnancy can adversely affect the fetus. During and after exercise, fetal bradycardia can occur. Therefore, recommendations should include not exceeding pre-pregnancy activity levels.³ Careful monitoring of exercise intensity is recommended by the American College of Obstetrics and Gynecology; the guideline is to maintain less than 70% of maximal heart rate.^17,18

The negative effects of exercise on the pregnant athlete are limited, but it is important to educate patients and to consider preventive strategies. One physiologic change that occurs during pregnancy is ligamentous laxity, which is caused by the hormone relaxin.¹⁶ Ligamentous laxity has the potential to put pregnant athletes at risk for soft-tissue and bony injury during impact sports. However, the positive effects of exercise during pregnancy include improved appetite, sleep, and emotional health.¹⁹ Aerobic exercise during pregnancy may reverse insulin resistance as demonstrated in animal studies; though this outcome has not been demonstrated in human studies,²⁰ women should be reassured that moderate exercise has overall beneficial effects.

Some research suggests that exercise may expose the fetus to hyperthermia, blood sugar changes, physical injury, and premature labor.¹⁶ Typically, fetal heat is dissipated from the mother. After intense exercise, maternal body temperature rises and leads to some degree of fetal hyperthermia.¹⁶ Animal model studies have suggested that hyperthermia may result in a slightly higher rate of congenital abnormalities. Pregnant women should keep their exercise routines to less than 60 minutes, should exercise in a thermally regulated environment, and should keep themselves hydrated to avoid fetal hyperthermia.¹⁸

Reduced blood flow, accompanied by a deficit of oxygen to the uterus and the developing fetus, is another concern for pregnant athletes. During exercise, when more blood is flowing to the muscles, less is flowing to the uterus.¹⁶ Furthermore, during the third trimester, women should avoid supine exercise, as venous outflow is poor with the body in that position.²¹

Elite athletes who continue training during pregnancy should be carefully counseled about adjusting their training regimens. Because of increased cardiac output and blood volume, the heart rate will be lower than usual, demanding an adjustment in interpretation. Blood cell counts do not increase as much as plasma volume does—often leading to relative anemia. For elite athletes, this means iron supplementation is crucial.²² Thermal regulation may be more difficult, as training regimens may demand prolonged exercise. Physicians should recommend adequate hydration for these athletes.¹⁸

Although continued exercise is generally safe for a pregnant athlete and her fetus, caution is required when there is increased risk for premature delivery, or other special conditions exist. Multiple gestation, placenta previa, history of early labor or premature births, and incompetent cervix all contraindicate aerobic exercise during pregnancy.¹⁸ With these exceptions in mind, physicians can safely counsel pregnant women to do moderate exercise 30 minutes every day.^17,18 Other recommendations are listed at the American College of Obstetricians and Gynecologists website.²³

4. Anterior cruciate ligament injuries

ACL injuries affect a staggering number of athletes. In the United States, approximately 100,000 people sustain these injuries annually.²⁴ As they occur up to 8 times more often in women than in men, ACL injuries are a top concern for physicians treating female athletes.

This disproportionate injury rate is influenced by differences between male and female anatomy. The width and shape of the femoral intercondylar notch have been studied as potential variables influencing the risk for ACL injury. Analysis of notch-view radiographs revealed a significant inverse relationship between notch width and ACL injury.²⁵ A-shaped notches, notches with a significantly larger base and a narrowed roof, were more prevalent in women but did not correlate with increased risk for ACL injury. Studies have shown that female athletes with a noncontact ACL injury have a higher lateral tibial plateau posterior slope; this slope is associated with increased peak anteromedial ACL strain, which may contribute to injury.²⁶ An analysis of magnetic resonance imaging scans in patients with and without ACL injury revealed that, for female patients, decreased femoral intercondylar notch width at the anterior outlet combined with increased lateral compartment posterior slope correlated best with risk for ACL injury.²⁷

Although static anatomical factors contribute to ACL injuries in female athletes, dynamic neuromuscular influences are potential opportunities for intervention. Female athletes with high relative quadriceps strength and weak hamstring strength may be at increased risk for ACL injury.²⁸ This “quadriceps dominance” becomes important in sports involving high-risk activities, such as running, cutting, pivoting, and jumping. In addition, compared with male athletes, female athletes demonstrate increased lateral trunk motion and knee valgus torque while landing during noncontact ACL tears, making core stability a factor in ACL injury.²⁹

The collaborative efforts of physicians, physical therapists, athletic trainers, and coaches have yielded multifactorial neuromuscular training programs for the prevention of noncontact ACL injuries. Ideal ACL prevention protocols involve sessions that last for at least 10 minutes and take place 3 times a week. At these sessions, exercises are focused on strengthening, balance, and proprioceptive training.³⁰ The programs last about 8 weeks, but sustained benefits require maintenance after the program has been completed and during the off-season. Program adherence must be encouraged and can be facilitated by varying workouts and raising risk awareness. The most effective programs have reduced the relative risk of noncontact ACL injuries by 75% to 100%.³¹ These promising results have led to increased focus on program implementation in an effort to prevent ACL injury.

5. Continued sex discrimination and social injustice

In 1972, Title IX was passed as part of the Education Amendments Act. Title IX states, “No person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any educational program or activity receiving Federal financial assistance.” Passage of this law, which has implications outside of athletic participation, marked an important turning point in women’s ability to participate equally in college sports.^32,33 The Civil Rights Restoration Act, passed in 1988, strengthened Title IX and made it applicable to all institutions receiving federal funding.³⁴ Before the 1970s, women typically were restricted to club sports, and funding and participation opportunities were weighted heavily toward men. Over the past 40 years, women’s participation in high school, college, and professional sports has taken a huge leap forward.³² For example, the number of women participating in high school sports increased from 294,000 (7.4% of all athletes) in 1972 to 3.4 million (>41% of all athletes) in 2014.

Despite advances in women’s civil rights, examples of inequality in US schools remain, particularly in the distribution of funding, which still strongly favors men’s football.³² Men’s sports receive 90% of media coverage.³³ In 2002, women represented 55% of college students but only 42% of varsity athletes.³⁴ The schools that have complied the least with Title IX are schools in the Midwest and the South and those with football teams.³⁴ Women are underrepresented as coaches, and funding continues to be disproportionately spent on men’s sports.

For women, the benefits of participating in sports are far-reaching and significant. These benefits include improvements in academic success, mental health, and responsible behavior.³³ Women’s gaining acceptance and respect throughout the athletic world seems to have carried over elsewhere. Although many institutions remain noncompliant with Title IX, efforts continue to have a strongly positive effect on gender equality in the United States.

Since Title IX passed in 1972, women have become exponentially more involved in competitive sports, from high school to professional levels. With more women engaging in serious athletics, the specific challenges they face have come to the forefront of sports medicine. These problems include the female athlete triad, concussions, exercise safety in pregnancy, anterior cruciate ligament (ACL) injuries, and continued sex discrimination and social injustice. Orthopedists treating female athletes should be aware of these problems, each of which is discussed in this review.

1. Female athlete triad

In 1992, the term female athlete triad was coined to describe 3 problems that often coexist in high-intensity female athletes.¹ Since then, the definition has evolved, but the problem has remained essentially the same. The modern definition incorporates menstrual abnormalities, low energy availability with or without disordered eating, and decreased bone mineral density (BMD).²

With intense exercise and weight loss comes a variety of menstrual disturbances.³ In affected athletes, the hypothalamus is underactivated, and changes in gonadotropin-releasing hormone and luteinizing hormone lead to decreased estrogen production. Research suggests abnormal menses result from having inadequate energy and insufficient caloric intake to support extensive exercise.¹ This phenomenon can occur in athletes in any sport but is most prevalent in lean-body sports, such as swimming, gymnastics, and ballet. The incidence of abnormal menses is as high as 79% in ballet dancers but only 5% in the general population.³ Menstrual abnormalities indicate hormonal abnormalities that can interfere with growth and maturation in young athletes.

Although full-blown eating disorders are uncommon among female athletes, disordered eating patterns are often found among women in competitive sports. Disordered eating can involve a spectrum of inadequate caloric intake and purging behavior, such as vomiting or laxative abuse, and has been reported in up to 25% of collegiate female athletes.⁴ Physicians must recognize these conditions and initiate counseling and treatment when appropriate. Women with disordered eating are at risk for developing electrolyte imbalances, malnutrition syndromes, and osteopenia.

Although careful evaluation and counseling are important, physicians must note that, in most cases, athletics participation may also protect against disordered eating and body image difficulties. A study of 146 college-age women found better body satisfaction among athletes than among nonathletes.⁵ Lean-sport athletes (eg, swimmers, gymnasts) were at higher risk for disordered eating and body image problems than other athletes were. Similarly, other studies have found that a majority of athletes have healthy eating habits.⁴

For poorly nourished and hormonally imbalanced female athletes, decreased BMD poses substantial risk. One study found a significant difference in BMD between athletes with amenorrhea and athletes with normal menses.⁶ In a cohort of female Navy recruits, those with amenorrhea were at 91% higher risk for stress fractures; calcium and vitamin D supplementation reduced risk by 20%.⁷ Osteopenia may be a special problem for prepubescent athletes. Girls who engage in intense exercise and have delayed menarche may have a low estrogen state, predisposing them to low BMD.³ Osteopenia and osteoporosis are difficult to reverse and can put these athletes at risk for stress fractures the rest of their lives. If unrecognized, stress fractures can end an athlete’s career.

Recommendations for dual-energy X-ray absorptiometry (DXA) include testing female athletes who have a diagnosed eating disorder, body mass index under 17.5, history of delayed menarche, oligomenorrhea, 2 prior stress fractures, or prior abnormal DXA scan. Complete testing recommendations appear in the 2014 consensus statement on the female athlete triad and return to sport.^2,8

Orthopedists performing physical examinations for sports participation can screen for the female athlete triad through thoughtful questioning about menstrual history, nutrition habits, and stress fracture symptoms. Best treatment for a diagnosed case of the triad is multidisciplinary care with strong social support. When abnormal menses are an issue, referral to a gynecologist or endocrinologist and consideration of estrogen replacement should be discussed. Some cases require a psychiatrist’s assistance in treating disordered eating. Athletic trainers, coaches, and parents should be involved over the treatment course.¹ Orthopedists must counsel women with osteopenia and osteoporosis about decreasing exercise to a safe level, improving nutritional intake, and supplementing with calcium (1200-1500 mg/d) and vitamin D (600-800 IU/d).^3,7

2. Concussions

Increasing awareness of males’ sport-related concussions, particularly of concussions that occur during National Football League practice and games, has made physicians and researchers more aware of the rate of concussion in female athletes. That rate has increased, and, according to some reports, the risk for sport-related injury is higher for female athletes.⁹ A study of high school athletes found that the rate of concussion in girl’s soccer was second only to that in football.¹⁰

Concussions are categorized as mild traumatic brain injuries, and manifestations of the diagnosis are divided into physical, emotional, cognitive, and observed symptoms. The spectrum of symptoms is wide, ranging from difficulty concentrating and thinking clearly to headaches and dizziness.¹¹ Compared with male athletes who sustain a concussion, female athletes report more of these concussive symptoms and have worse visual memory scores.¹²

Efforts to change sports at the player level have been resisted. Helmets have been proposed for field hockey and lacrosse but have not passed stringent concussion testing. In soccer, which has a high rate of concussion, a reform to eliminate heading the ball has been considered. Resistance to these suggestions stems from the thought that changes could alter the traditions of the games. Some individuals have indicated that helmets may give players a false sense of security and thereby cause them to play more aggressively.

Orthopedic surgeons must be aware of concussion symptoms. Multiple concussions may have a cumulative effect on functional ability and emotional well-being and may lead to chronic traumatic encephalopathy.¹³ Concern about the long-term effects of concussion has led to the implementation of universal “return to play” laws. These laws vary by state but have 3 steps in common: Educate coaches, players, and athletes; remove athletes from play; and obtain health care professionals’ permission to return to play.¹⁴ These guidelines set up an action plan for treating an athlete who has sustained a concussion.

Encouraging results of educating coaches have been noted. Coaches who were given Centers for Disease Control and Prevention–sponsored material on preventing, recognizing, and responding to concussions were able to effectively address concussions; 6 months later, 63% were better able to appreciate the severity of concussions.¹⁵ Continued education of athletic communities should help bring this injury to the attention of those treating female athletes.

3. Exercise safety in pregnancy

Women in sports can continue their athletic regimens during pregnancy. It is important to address challenges to the pregnant woman and to the fetus when assessing the risks of exercise.

The physiologic changes that occur during pregnancy may affect how a pregnant athlete responds to stress. Plasma volume, red blood cell volume, and cardiac function and output all increase during normal pregnancy.^3,16 Abnormal heart rate during pregnancy can adversely affect the fetus. During and after exercise, fetal bradycardia can occur. Therefore, recommendations should include not exceeding pre-pregnancy activity levels.³ Careful monitoring of exercise intensity is recommended by the American College of Obstetrics and Gynecology; the guideline is to maintain less than 70% of maximal heart rate.^17,18

The negative effects of exercise on the pregnant athlete are limited, but it is important to educate patients and to consider preventive strategies. One physiologic change that occurs during pregnancy is ligamentous laxity, which is caused by the hormone relaxin.¹⁶ Ligamentous laxity has the potential to put pregnant athletes at risk for soft-tissue and bony injury during impact sports. However, the positive effects of exercise during pregnancy include improved appetite, sleep, and emotional health.¹⁹ Aerobic exercise during pregnancy may reverse insulin resistance as demonstrated in animal studies; though this outcome has not been demonstrated in human studies,²⁰ women should be reassured that moderate exercise has overall beneficial effects.

Some research suggests that exercise may expose the fetus to hyperthermia, blood sugar changes, physical injury, and premature labor.¹⁶ Typically, fetal heat is dissipated from the mother. After intense exercise, maternal body temperature rises and leads to some degree of fetal hyperthermia.¹⁶ Animal model studies have suggested that hyperthermia may result in a slightly higher rate of congenital abnormalities. Pregnant women should keep their exercise routines to less than 60 minutes, should exercise in a thermally regulated environment, and should keep themselves hydrated to avoid fetal hyperthermia.¹⁸

Reduced blood flow, accompanied by a deficit of oxygen to the uterus and the developing fetus, is another concern for pregnant athletes. During exercise, when more blood is flowing to the muscles, less is flowing to the uterus.¹⁶ Furthermore, during the third trimester, women should avoid supine exercise, as venous outflow is poor with the body in that position.²¹

Elite athletes who continue training during pregnancy should be carefully counseled about adjusting their training regimens. Because of increased cardiac output and blood volume, the heart rate will be lower than usual, demanding an adjustment in interpretation. Blood cell counts do not increase as much as plasma volume does—often leading to relative anemia. For elite athletes, this means iron supplementation is crucial.²² Thermal regulation may be more difficult, as training regimens may demand prolonged exercise. Physicians should recommend adequate hydration for these athletes.¹⁸

Although continued exercise is generally safe for a pregnant athlete and her fetus, caution is required when there is increased risk for premature delivery, or other special conditions exist. Multiple gestation, placenta previa, history of early labor or premature births, and incompetent cervix all contraindicate aerobic exercise during pregnancy.¹⁸ With these exceptions in mind, physicians can safely counsel pregnant women to do moderate exercise 30 minutes every day.^17,18 Other recommendations are listed at the American College of Obstetricians and Gynecologists website.²³

4. Anterior cruciate ligament injuries

ACL injuries affect a staggering number of athletes. In the United States, approximately 100,000 people sustain these injuries annually.²⁴ As they occur up to 8 times more often in women than in men, ACL injuries are a top concern for physicians treating female athletes.

This disproportionate injury rate is influenced by differences between male and female anatomy. The width and shape of the femoral intercondylar notch have been studied as potential variables influencing the risk for ACL injury. Analysis of notch-view radiographs revealed a significant inverse relationship between notch width and ACL injury.²⁵ A-shaped notches, notches with a significantly larger base and a narrowed roof, were more prevalent in women but did not correlate with increased risk for ACL injury. Studies have shown that female athletes with a noncontact ACL injury have a higher lateral tibial plateau posterior slope; this slope is associated with increased peak anteromedial ACL strain, which may contribute to injury.²⁶ An analysis of magnetic resonance imaging scans in patients with and without ACL injury revealed that, for female patients, decreased femoral intercondylar notch width at the anterior outlet combined with increased lateral compartment posterior slope correlated best with risk for ACL injury.²⁷

Although static anatomical factors contribute to ACL injuries in female athletes, dynamic neuromuscular influences are potential opportunities for intervention. Female athletes with high relative quadriceps strength and weak hamstring strength may be at increased risk for ACL injury.²⁸ This “quadriceps dominance” becomes important in sports involving high-risk activities, such as running, cutting, pivoting, and jumping. In addition, compared with male athletes, female athletes demonstrate increased lateral trunk motion and knee valgus torque while landing during noncontact ACL tears, making core stability a factor in ACL injury.²⁹

The collaborative efforts of physicians, physical therapists, athletic trainers, and coaches have yielded multifactorial neuromuscular training programs for the prevention of noncontact ACL injuries. Ideal ACL prevention protocols involve sessions that last for at least 10 minutes and take place 3 times a week. At these sessions, exercises are focused on strengthening, balance, and proprioceptive training.³⁰ The programs last about 8 weeks, but sustained benefits require maintenance after the program has been completed and during the off-season. Program adherence must be encouraged and can be facilitated by varying workouts and raising risk awareness. The most effective programs have reduced the relative risk of noncontact ACL injuries by 75% to 100%.³¹ These promising results have led to increased focus on program implementation in an effort to prevent ACL injury.

5. Continued sex discrimination and social injustice

In 1972, Title IX was passed as part of the Education Amendments Act. Title IX states, “No person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any educational program or activity receiving Federal financial assistance.” Passage of this law, which has implications outside of athletic participation, marked an important turning point in women’s ability to participate equally in college sports.^32,33 The Civil Rights Restoration Act, passed in 1988, strengthened Title IX and made it applicable to all institutions receiving federal funding.³⁴ Before the 1970s, women typically were restricted to club sports, and funding and participation opportunities were weighted heavily toward men. Over the past 40 years, women’s participation in high school, college, and professional sports has taken a huge leap forward.³² For example, the number of women participating in high school sports increased from 294,000 (7.4% of all athletes) in 1972 to 3.4 million (>41% of all athletes) in 2014.

Despite advances in women’s civil rights, examples of inequality in US schools remain, particularly in the distribution of funding, which still strongly favors men’s football.³² Men’s sports receive 90% of media coverage.³³ In 2002, women represented 55% of college students but only 42% of varsity athletes.³⁴ The schools that have complied the least with Title IX are schools in the Midwest and the South and those with football teams.³⁴ Women are underrepresented as coaches, and funding continues to be disproportionately spent on men’s sports.

For women, the benefits of participating in sports are far-reaching and significant. These benefits include improvements in academic success, mental health, and responsible behavior.³³ Women’s gaining acceptance and respect throughout the athletic world seems to have carried over elsewhere. Although many institutions remain noncompliant with Title IX, efforts continue to have a strongly positive effect on gender equality in the United States.

Since Title IX passed in 1972, women have become exponentially more involved in competitive sports, from high school to professional levels. With more women engaging in serious athletics, the specific challenges they face have come to the forefront of sports medicine. These problems include the female athlete triad, concussions, exercise safety in pregnancy, anterior cruciate ligament (ACL) injuries, and continued sex discrimination and social injustice. Orthopedists treating female athletes should be aware of these problems, each of which is discussed in this review.

1. Female athlete triad

In 1992, the term female athlete triad was coined to describe 3 problems that often coexist in high-intensity female athletes.¹ Since then, the definition has evolved, but the problem has remained essentially the same. The modern definition incorporates menstrual abnormalities, low energy availability with or without disordered eating, and decreased bone mineral density (BMD).²

With intense exercise and weight loss comes a variety of menstrual disturbances.³ In affected athletes, the hypothalamus is underactivated, and changes in gonadotropin-releasing hormone and luteinizing hormone lead to decreased estrogen production. Research suggests abnormal menses result from having inadequate energy and insufficient caloric intake to support extensive exercise.¹ This phenomenon can occur in athletes in any sport but is most prevalent in lean-body sports, such as swimming, gymnastics, and ballet. The incidence of abnormal menses is as high as 79% in ballet dancers but only 5% in the general population.³ Menstrual abnormalities indicate hormonal abnormalities that can interfere with growth and maturation in young athletes.

Although full-blown eating disorders are uncommon among female athletes, disordered eating patterns are often found among women in competitive sports. Disordered eating can involve a spectrum of inadequate caloric intake and purging behavior, such as vomiting or laxative abuse, and has been reported in up to 25% of collegiate female athletes.⁴ Physicians must recognize these conditions and initiate counseling and treatment when appropriate. Women with disordered eating are at risk for developing electrolyte imbalances, malnutrition syndromes, and osteopenia.

Although careful evaluation and counseling are important, physicians must note that, in most cases, athletics participation may also protect against disordered eating and body image difficulties. A study of 146 college-age women found better body satisfaction among athletes than among nonathletes.⁵ Lean-sport athletes (eg, swimmers, gymnasts) were at higher risk for disordered eating and body image problems than other athletes were. Similarly, other studies have found that a majority of athletes have healthy eating habits.⁴

For poorly nourished and hormonally imbalanced female athletes, decreased BMD poses substantial risk. One study found a significant difference in BMD between athletes with amenorrhea and athletes with normal menses.⁶ In a cohort of female Navy recruits, those with amenorrhea were at 91% higher risk for stress fractures; calcium and vitamin D supplementation reduced risk by 20%.⁷ Osteopenia may be a special problem for prepubescent athletes. Girls who engage in intense exercise and have delayed menarche may have a low estrogen state, predisposing them to low BMD.³ Osteopenia and osteoporosis are difficult to reverse and can put these athletes at risk for stress fractures the rest of their lives. If unrecognized, stress fractures can end an athlete’s career.

Recommendations for dual-energy X-ray absorptiometry (DXA) include testing female athletes who have a diagnosed eating disorder, body mass index under 17.5, history of delayed menarche, oligomenorrhea, 2 prior stress fractures, or prior abnormal DXA scan. Complete testing recommendations appear in the 2014 consensus statement on the female athlete triad and return to sport.^2,8

Orthopedists performing physical examinations for sports participation can screen for the female athlete triad through thoughtful questioning about menstrual history, nutrition habits, and stress fracture symptoms. Best treatment for a diagnosed case of the triad is multidisciplinary care with strong social support. When abnormal menses are an issue, referral to a gynecologist or endocrinologist and consideration of estrogen replacement should be discussed. Some cases require a psychiatrist’s assistance in treating disordered eating. Athletic trainers, coaches, and parents should be involved over the treatment course.¹ Orthopedists must counsel women with osteopenia and osteoporosis about decreasing exercise to a safe level, improving nutritional intake, and supplementing with calcium (1200-1500 mg/d) and vitamin D (600-800 IU/d).^3,7

2. Concussions

Increasing awareness of males’ sport-related concussions, particularly of concussions that occur during National Football League practice and games, has made physicians and researchers more aware of the rate of concussion in female athletes. That rate has increased, and, according to some reports, the risk for sport-related injury is higher for female athletes.⁹ A study of high school athletes found that the rate of concussion in girl’s soccer was second only to that in football.¹⁰

Concussions are categorized as mild traumatic brain injuries, and manifestations of the diagnosis are divided into physical, emotional, cognitive, and observed symptoms. The spectrum of symptoms is wide, ranging from difficulty concentrating and thinking clearly to headaches and dizziness.¹¹ Compared with male athletes who sustain a concussion, female athletes report more of these concussive symptoms and have worse visual memory scores.¹²

Efforts to change sports at the player level have been resisted. Helmets have been proposed for field hockey and lacrosse but have not passed stringent concussion testing. In soccer, which has a high rate of concussion, a reform to eliminate heading the ball has been considered. Resistance to these suggestions stems from the thought that changes could alter the traditions of the games. Some individuals have indicated that helmets may give players a false sense of security and thereby cause them to play more aggressively.

Orthopedic surgeons must be aware of concussion symptoms. Multiple concussions may have a cumulative effect on functional ability and emotional well-being and may lead to chronic traumatic encephalopathy.¹³ Concern about the long-term effects of concussion has led to the implementation of universal “return to play” laws. These laws vary by state but have 3 steps in common: Educate coaches, players, and athletes; remove athletes from play; and obtain health care professionals’ permission to return to play.¹⁴ These guidelines set up an action plan for treating an athlete who has sustained a concussion.

Encouraging results of educating coaches have been noted. Coaches who were given Centers for Disease Control and Prevention–sponsored material on preventing, recognizing, and responding to concussions were able to effectively address concussions; 6 months later, 63% were better able to appreciate the severity of concussions.¹⁵ Continued education of athletic communities should help bring this injury to the attention of those treating female athletes.

3. Exercise safety in pregnancy

Women in sports can continue their athletic regimens during pregnancy. It is important to address challenges to the pregnant woman and to the fetus when assessing the risks of exercise.

The physiologic changes that occur during pregnancy may affect how a pregnant athlete responds to stress. Plasma volume, red blood cell volume, and cardiac function and output all increase during normal pregnancy.^3,16 Abnormal heart rate during pregnancy can adversely affect the fetus. During and after exercise, fetal bradycardia can occur. Therefore, recommendations should include not exceeding pre-pregnancy activity levels.³ Careful monitoring of exercise intensity is recommended by the American College of Obstetrics and Gynecology; the guideline is to maintain less than 70% of maximal heart rate.^17,18

The negative effects of exercise on the pregnant athlete are limited, but it is important to educate patients and to consider preventive strategies. One physiologic change that occurs during pregnancy is ligamentous laxity, which is caused by the hormone relaxin.¹⁶ Ligamentous laxity has the potential to put pregnant athletes at risk for soft-tissue and bony injury during impact sports. However, the positive effects of exercise during pregnancy include improved appetite, sleep, and emotional health.¹⁹ Aerobic exercise during pregnancy may reverse insulin resistance as demonstrated in animal studies; though this outcome has not been demonstrated in human studies,²⁰ women should be reassured that moderate exercise has overall beneficial effects.

Some research suggests that exercise may expose the fetus to hyperthermia, blood sugar changes, physical injury, and premature labor.¹⁶ Typically, fetal heat is dissipated from the mother. After intense exercise, maternal body temperature rises and leads to some degree of fetal hyperthermia.¹⁶ Animal model studies have suggested that hyperthermia may result in a slightly higher rate of congenital abnormalities. Pregnant women should keep their exercise routines to less than 60 minutes, should exercise in a thermally regulated environment, and should keep themselves hydrated to avoid fetal hyperthermia.¹⁸

Reduced blood flow, accompanied by a deficit of oxygen to the uterus and the developing fetus, is another concern for pregnant athletes. During exercise, when more blood is flowing to the muscles, less is flowing to the uterus.¹⁶ Furthermore, during the third trimester, women should avoid supine exercise, as venous outflow is poor with the body in that position.²¹

Elite athletes who continue training during pregnancy should be carefully counseled about adjusting their training regimens. Because of increased cardiac output and blood volume, the heart rate will be lower than usual, demanding an adjustment in interpretation. Blood cell counts do not increase as much as plasma volume does—often leading to relative anemia. For elite athletes, this means iron supplementation is crucial.²² Thermal regulation may be more difficult, as training regimens may demand prolonged exercise. Physicians should recommend adequate hydration for these athletes.¹⁸

Although continued exercise is generally safe for a pregnant athlete and her fetus, caution is required when there is increased risk for premature delivery, or other special conditions exist. Multiple gestation, placenta previa, history of early labor or premature births, and incompetent cervix all contraindicate aerobic exercise during pregnancy.¹⁸ With these exceptions in mind, physicians can safely counsel pregnant women to do moderate exercise 30 minutes every day.^17,18 Other recommendations are listed at the American College of Obstetricians and Gynecologists website.²³

4. Anterior cruciate ligament injuries

ACL injuries affect a staggering number of athletes. In the United States, approximately 100,000 people sustain these injuries annually.²⁴ As they occur up to 8 times more often in women than in men, ACL injuries are a top concern for physicians treating female athletes.

This disproportionate injury rate is influenced by differences between male and female anatomy. The width and shape of the femoral intercondylar notch have been studied as potential variables influencing the risk for ACL injury. Analysis of notch-view radiographs revealed a significant inverse relationship between notch width and ACL injury.²⁵ A-shaped notches, notches with a significantly larger base and a narrowed roof, were more prevalent in women but did not correlate with increased risk for ACL injury. Studies have shown that female athletes with a noncontact ACL injury have a higher lateral tibial plateau posterior slope; this slope is associated with increased peak anteromedial ACL strain, which may contribute to injury.²⁶ An analysis of magnetic resonance imaging scans in patients with and without ACL injury revealed that, for female patients, decreased femoral intercondylar notch width at the anterior outlet combined with increased lateral compartment posterior slope correlated best with risk for ACL injury.²⁷

Although static anatomical factors contribute to ACL injuries in female athletes, dynamic neuromuscular influences are potential opportunities for intervention. Female athletes with high relative quadriceps strength and weak hamstring strength may be at increased risk for ACL injury.²⁸ This “quadriceps dominance” becomes important in sports involving high-risk activities, such as running, cutting, pivoting, and jumping. In addition, compared with male athletes, female athletes demonstrate increased lateral trunk motion and knee valgus torque while landing during noncontact ACL tears, making core stability a factor in ACL injury.²⁹

The collaborative efforts of physicians, physical therapists, athletic trainers, and coaches have yielded multifactorial neuromuscular training programs for the prevention of noncontact ACL injuries. Ideal ACL prevention protocols involve sessions that last for at least 10 minutes and take place 3 times a week. At these sessions, exercises are focused on strengthening, balance, and proprioceptive training.³⁰ The programs last about 8 weeks, but sustained benefits require maintenance after the program has been completed and during the off-season. Program adherence must be encouraged and can be facilitated by varying workouts and raising risk awareness. The most effective programs have reduced the relative risk of noncontact ACL injuries by 75% to 100%.³¹ These promising results have led to increased focus on program implementation in an effort to prevent ACL injury.

5. Continued sex discrimination and social injustice

In 1972, Title IX was passed as part of the Education Amendments Act. Title IX states, “No person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any educational program or activity receiving Federal financial assistance.” Passage of this law, which has implications outside of athletic participation, marked an important turning point in women’s ability to participate equally in college sports.^32,33 The Civil Rights Restoration Act, passed in 1988, strengthened Title IX and made it applicable to all institutions receiving federal funding.³⁴ Before the 1970s, women typically were restricted to club sports, and funding and participation opportunities were weighted heavily toward men. Over the past 40 years, women’s participation in high school, college, and professional sports has taken a huge leap forward.³² For example, the number of women participating in high school sports increased from 294,000 (7.4% of all athletes) in 1972 to 3.4 million (>41% of all athletes) in 2014.

Despite advances in women’s civil rights, examples of inequality in US schools remain, particularly in the distribution of funding, which still strongly favors men’s football.³² Men’s sports receive 90% of media coverage.³³ In 2002, women represented 55% of college students but only 42% of varsity athletes.³⁴ The schools that have complied the least with Title IX are schools in the Midwest and the South and those with football teams.³⁴ Women are underrepresented as coaches, and funding continues to be disproportionately spent on men’s sports.

For women, the benefits of participating in sports are far-reaching and significant. These benefits include improvements in academic success, mental health, and responsible behavior.³³ Women’s gaining acceptance and respect throughout the athletic world seems to have carried over elsewhere. Although many institutions remain noncompliant with Title IX, efforts continue to have a strongly positive effect on gender equality in the United States.

A new and novel technique for obtaining the patient-directed valgus stress radiograph of the knee.

To read the authors' full article click here.

Vidyard Video

A new and novel technique for obtaining the patient-directed valgus stress radiograph of the knee.

To read the authors' full article click here.

Vidyard Video

A new and novel technique for obtaining the patient-directed valgus stress radiograph of the knee.

To read the authors' full article click here.

Vidyard Video

Medial-compartment partial knee arthroplasty (unicompartmental replacement) is an accepted surgical intervention for anteromedial osteoarthritis of the knee.1 The radiographic investigations required in the workup of these patients should include weight-bearing standing anteroposterior (AP), lateral, and sunrise (Merchant) views, as well as a valgus stress AP radiograph to assess the functionality of the lateral compartment. The method of properly obtaining the valgus stress film has been well described by the Oxford Group.2 Its recommended radiographic technique requires that a surgeon or a radiologic technologist perform the valgus stress maneuver, manually, while another technologist shoots the film. The 2 consequences of this technique are that it requires 2 individuals to obtain the film, and it subjects the individual who is applying the stress to some level of radiation exposure, which is undesirable. Because of this and the time inconvenience, many surgeons omit the valgus stress radiograph, which can lead to the adverse outcome of missing a lateral compartment that is functionally incompetent, resulting in the potential for early lateral compartment progression of osteoarthritis and the need for revision surgery, usually to a total knee arthroplasty.

In an attempt to mitigate these barriers to obtaining the necessary valgus stress radiograph, Dr. Mauerhan’s team developed a technique that could be done with the assistance of the patient and would require only 1 technologist to perform. Additionally, this project was a quality improvement initiative, because it lowered radiation exposure to all personnel involved in obtaining the correct films.

Materials and Methods

We initiated the project using weight-bearing strategies to impart the valgus stress view of the knee. After trying several different wedges and blocks, and varying patient instructions, we realized a different approach to this problem would be required to find an acceptable solution. We redirected our efforts to effectively performing the stress view with the patient in a supine position on the radiograph table. Ultimately, we decided that a much stiffer wedge and a denser object to squeeze would facilitate obtaining a proper film. Considering all available options, a youth size 4 soccer ball (diameter, 11 in) was introduced along with a slightly larger positioning wedge. The soccer ball was wrapped with 4-in Coban wrap (3M) to create a nonslip surface. This change in patient positioning, along with a standardized 7º to 10º cephalic radiographic tube angulation, helped to correct issues with tibial plateau visualization. Once these changes were enacted, we obtained fairly consistent positive results, and we instituted this patient-directed valgus stress view of the knee, along with a manual valgus stress view for comparison.

The protocol for obtaining the patient-directed valgus stress view of the knee is as follows: The patient lays supine with a dense 45º spine-positioning wedge (Burlington Medical Supplies) placed under both knees and the patient’s heels on the examining table. The radiographic tube is angled cephalad 7º to 10º centered on the inferior pole of the patella, using a 40-in source to image-receptor distance, collimated to part; the image receptor is placed under the affected knee, below the positioning wedge. The affected knee is rotated to the “true” AP position (the patella will be centered between the femoral condyles on the AP exposure), and the ball is placed between the patient’s legs just above the ankle joint. The technologist demonstrates to the patient how to squeeze the ball while maintaining contact of heels with the table. The technologist can exit the room and obtain the exposure, which is taken while the patient is squeezing the ball, as shown in Figures 1A and 1B. Examples of the standing AP, manual stress, and patient-directed valgus radiographs are shown in Figures 2A-2C. The entire technique is demonstrated in the Video.

Vidyard Video

 

 

Results

During the 9 months of this quality improvement project, 78 examinations were performed. Five studies did not show complete correction of the varus deformity. Of these, 3 showed complete correction on a manual valgus stress radiograph, and 2 did not, contraindicating the use of partial knee replacement. Three patients displayed collapse of the lateral compartment, indicating a nonfunctional lateral compartment, and, therefore, were also a contraindication to partial knee arthroplasty. The remaining 70 patients had identical radiographic results with both the manual and patient-directed valgus stress tests. There was no instance of examination failure or need to repeat as a result of difficulty of the examination for the patient. Repeat films because of positioning errors were very rare, usually early in the learning curve, and no more prevalent than when using the manual stress method. The technique was reproducible and easy to teach and adopt.

 

 

Discussion

In total, 73 patients (93.5%) with the patient-directed stress film showed the desired result, either correction of the medial compartment narrowing in conjunction with an intact lateral compartment or narrowing of the lateral compartment. Of the 5 patients (6.5%) whose patient-directed stress films did not show correction of the varus deformity, 3 patients displayed correction with a manually applied stress radiograph and 2 did not. Based on this observation, our recommendation would be for those patients who do not show adequate correction on the patient-directed stress radiograph to have a manual examination to establish the presence or absence of the desired correction.

Performing a valgus stress radiograph is an integral part of the investigation to determine if the patient is an appropriate candidate for partial knee arthroplasty.3 The historical, manually performed valgus stress radiograph requires 2 individuals, 1 to apply the stress with the patient on the table and 1 to shoot the exposure. For the individual or individuals applying this stress, there is an increased radiation exposure that would be undesirable over a long career. The authors developed a new technique using a commercially available spinal positioning wedge and 11-in youth soccer ball wrapped with Coban wrap, as described, which is economical and easy to obtain and use in the clinical setting. We believe this cost-effective method will offer surgeons who perform partial knee arthroplasty a novel method to obtain the important information gleaned from the valgus stress radiograph and to improve surgical outcomes through the preoperative assessment of the lateral compartment. Additionally, as a quality and safety improvement initiative, we believe this technique will reduce radiographic exposure for those performing these studies, and, because the examination can be carried out by a single technologist, it will significantly improve efficiency in the radiology suite.

Conclusion

We have developed a new method of obtaining the important valgus stress radiograph as part of the workup of patients with medial-compartment osteoarthritis of the knee. The technique can be performed with easily obtainable, commercially available products and is reliable 93.5% of the time. It also adds to the efficiency of the radiology suite and reduces radiographic exposure for technologists.

Medial-compartment partial knee arthroplasty (unicompartmental replacement) is an accepted surgical intervention for anteromedial osteoarthritis of the knee.1 The radiographic investigations required in the workup of these patients should include weight-bearing standing anteroposterior (AP), lateral, and sunrise (Merchant) views, as well as a valgus stress AP radiograph to assess the functionality of the lateral compartment. The method of properly obtaining the valgus stress film has been well described by the Oxford Group.2 Its recommended radiographic technique requires that a surgeon or a radiologic technologist perform the valgus stress maneuver, manually, while another technologist shoots the film. The 2 consequences of this technique are that it requires 2 individuals to obtain the film, and it subjects the individual who is applying the stress to some level of radiation exposure, which is undesirable. Because of this and the time inconvenience, many surgeons omit the valgus stress radiograph, which can lead to the adverse outcome of missing a lateral compartment that is functionally incompetent, resulting in the potential for early lateral compartment progression of osteoarthritis and the need for revision surgery, usually to a total knee arthroplasty.

In an attempt to mitigate these barriers to obtaining the necessary valgus stress radiograph, Dr. Mauerhan’s team developed a technique that could be done with the assistance of the patient and would require only 1 technologist to perform. Additionally, this project was a quality improvement initiative, because it lowered radiation exposure to all personnel involved in obtaining the correct films.

Materials and Methods

We initiated the project using weight-bearing strategies to impart the valgus stress view of the knee. After trying several different wedges and blocks, and varying patient instructions, we realized a different approach to this problem would be required to find an acceptable solution. We redirected our efforts to effectively performing the stress view with the patient in a supine position on the radiograph table. Ultimately, we decided that a much stiffer wedge and a denser object to squeeze would facilitate obtaining a proper film. Considering all available options, a youth size 4 soccer ball (diameter, 11 in) was introduced along with a slightly larger positioning wedge. The soccer ball was wrapped with 4-in Coban wrap (3M) to create a nonslip surface. This change in patient positioning, along with a standardized 7º to 10º cephalic radiographic tube angulation, helped to correct issues with tibial plateau visualization. Once these changes were enacted, we obtained fairly consistent positive results, and we instituted this patient-directed valgus stress view of the knee, along with a manual valgus stress view for comparison.

The protocol for obtaining the patient-directed valgus stress view of the knee is as follows: The patient lays supine with a dense 45º spine-positioning wedge (Burlington Medical Supplies) placed under both knees and the patient’s heels on the examining table. The radiographic tube is angled cephalad 7º to 10º centered on the inferior pole of the patella, using a 40-in source to image-receptor distance, collimated to part; the image receptor is placed under the affected knee, below the positioning wedge. The affected knee is rotated to the “true” AP position (the patella will be centered between the femoral condyles on the AP exposure), and the ball is placed between the patient’s legs just above the ankle joint. The technologist demonstrates to the patient how to squeeze the ball while maintaining contact of heels with the table. The technologist can exit the room and obtain the exposure, which is taken while the patient is squeezing the ball, as shown in Figures 1A and 1B. Examples of the standing AP, manual stress, and patient-directed valgus radiographs are shown in Figures 2A-2C. The entire technique is demonstrated in the Video.

Vidyard Video

 

 

Results

During the 9 months of this quality improvement project, 78 examinations were performed. Five studies did not show complete correction of the varus deformity. Of these, 3 showed complete correction on a manual valgus stress radiograph, and 2 did not, contraindicating the use of partial knee replacement. Three patients displayed collapse of the lateral compartment, indicating a nonfunctional lateral compartment, and, therefore, were also a contraindication to partial knee arthroplasty. The remaining 70 patients had identical radiographic results with both the manual and patient-directed valgus stress tests. There was no instance of examination failure or need to repeat as a result of difficulty of the examination for the patient. Repeat films because of positioning errors were very rare, usually early in the learning curve, and no more prevalent than when using the manual stress method. The technique was reproducible and easy to teach and adopt.

 

 

Discussion

In total, 73 patients (93.5%) with the patient-directed stress film showed the desired result, either correction of the medial compartment narrowing in conjunction with an intact lateral compartment or narrowing of the lateral compartment. Of the 5 patients (6.5%) whose patient-directed stress films did not show correction of the varus deformity, 3 patients displayed correction with a manually applied stress radiograph and 2 did not. Based on this observation, our recommendation would be for those patients who do not show adequate correction on the patient-directed stress radiograph to have a manual examination to establish the presence or absence of the desired correction.

Performing a valgus stress radiograph is an integral part of the investigation to determine if the patient is an appropriate candidate for partial knee arthroplasty.3 The historical, manually performed valgus stress radiograph requires 2 individuals, 1 to apply the stress with the patient on the table and 1 to shoot the exposure. For the individual or individuals applying this stress, there is an increased radiation exposure that would be undesirable over a long career. The authors developed a new technique using a commercially available spinal positioning wedge and 11-in youth soccer ball wrapped with Coban wrap, as described, which is economical and easy to obtain and use in the clinical setting. We believe this cost-effective method will offer surgeons who perform partial knee arthroplasty a novel method to obtain the important information gleaned from the valgus stress radiograph and to improve surgical outcomes through the preoperative assessment of the lateral compartment. Additionally, as a quality and safety improvement initiative, we believe this technique will reduce radiographic exposure for those performing these studies, and, because the examination can be carried out by a single technologist, it will significantly improve efficiency in the radiology suite.

Conclusion

We have developed a new method of obtaining the important valgus stress radiograph as part of the workup of patients with medial-compartment osteoarthritis of the knee. The technique can be performed with easily obtainable, commercially available products and is reliable 93.5% of the time. It also adds to the efficiency of the radiology suite and reduces radiographic exposure for technologists.

Medial-compartment partial knee arthroplasty (unicompartmental replacement) is an accepted surgical intervention for anteromedial osteoarthritis of the knee.1 The radiographic investigations required in the workup of these patients should include weight-bearing standing anteroposterior (AP), lateral, and sunrise (Merchant) views, as well as a valgus stress AP radiograph to assess the functionality of the lateral compartment. The method of properly obtaining the valgus stress film has been well described by the Oxford Group.2 Its recommended radiographic technique requires that a surgeon or a radiologic technologist perform the valgus stress maneuver, manually, while another technologist shoots the film. The 2 consequences of this technique are that it requires 2 individuals to obtain the film, and it subjects the individual who is applying the stress to some level of radiation exposure, which is undesirable. Because of this and the time inconvenience, many surgeons omit the valgus stress radiograph, which can lead to the adverse outcome of missing a lateral compartment that is functionally incompetent, resulting in the potential for early lateral compartment progression of osteoarthritis and the need for revision surgery, usually to a total knee arthroplasty.

In an attempt to mitigate these barriers to obtaining the necessary valgus stress radiograph, Dr. Mauerhan’s team developed a technique that could be done with the assistance of the patient and would require only 1 technologist to perform. Additionally, this project was a quality improvement initiative, because it lowered radiation exposure to all personnel involved in obtaining the correct films.

Materials and Methods

We initiated the project using weight-bearing strategies to impart the valgus stress view of the knee. After trying several different wedges and blocks, and varying patient instructions, we realized a different approach to this problem would be required to find an acceptable solution. We redirected our efforts to effectively performing the stress view with the patient in a supine position on the radiograph table. Ultimately, we decided that a much stiffer wedge and a denser object to squeeze would facilitate obtaining a proper film. Considering all available options, a youth size 4 soccer ball (diameter, 11 in) was introduced along with a slightly larger positioning wedge. The soccer ball was wrapped with 4-in Coban wrap (3M) to create a nonslip surface. This change in patient positioning, along with a standardized 7º to 10º cephalic radiographic tube angulation, helped to correct issues with tibial plateau visualization. Once these changes were enacted, we obtained fairly consistent positive results, and we instituted this patient-directed valgus stress view of the knee, along with a manual valgus stress view for comparison.

The protocol for obtaining the patient-directed valgus stress view of the knee is as follows: The patient lays supine with a dense 45º spine-positioning wedge (Burlington Medical Supplies) placed under both knees and the patient’s heels on the examining table. The radiographic tube is angled cephalad 7º to 10º centered on the inferior pole of the patella, using a 40-in source to image-receptor distance, collimated to part; the image receptor is placed under the affected knee, below the positioning wedge. The affected knee is rotated to the “true” AP position (the patella will be centered between the femoral condyles on the AP exposure), and the ball is placed between the patient’s legs just above the ankle joint. The technologist demonstrates to the patient how to squeeze the ball while maintaining contact of heels with the table. The technologist can exit the room and obtain the exposure, which is taken while the patient is squeezing the ball, as shown in Figures 1A and 1B. Examples of the standing AP, manual stress, and patient-directed valgus radiographs are shown in Figures 2A-2C. The entire technique is demonstrated in the Video.

Vidyard Video

 

 

Results

During the 9 months of this quality improvement project, 78 examinations were performed. Five studies did not show complete correction of the varus deformity. Of these, 3 showed complete correction on a manual valgus stress radiograph, and 2 did not, contraindicating the use of partial knee replacement. Three patients displayed collapse of the lateral compartment, indicating a nonfunctional lateral compartment, and, therefore, were also a contraindication to partial knee arthroplasty. The remaining 70 patients had identical radiographic results with both the manual and patient-directed valgus stress tests. There was no instance of examination failure or need to repeat as a result of difficulty of the examination for the patient. Repeat films because of positioning errors were very rare, usually early in the learning curve, and no more prevalent than when using the manual stress method. The technique was reproducible and easy to teach and adopt.

 

 

Discussion

In total, 73 patients (93.5%) with the patient-directed stress film showed the desired result, either correction of the medial compartment narrowing in conjunction with an intact lateral compartment or narrowing of the lateral compartment. Of the 5 patients (6.5%) whose patient-directed stress films did not show correction of the varus deformity, 3 patients displayed correction with a manually applied stress radiograph and 2 did not. Based on this observation, our recommendation would be for those patients who do not show adequate correction on the patient-directed stress radiograph to have a manual examination to establish the presence or absence of the desired correction.

Performing a valgus stress radiograph is an integral part of the investigation to determine if the patient is an appropriate candidate for partial knee arthroplasty.3 The historical, manually performed valgus stress radiograph requires 2 individuals, 1 to apply the stress with the patient on the table and 1 to shoot the exposure. For the individual or individuals applying this stress, there is an increased radiation exposure that would be undesirable over a long career. The authors developed a new technique using a commercially available spinal positioning wedge and 11-in youth soccer ball wrapped with Coban wrap, as described, which is economical and easy to obtain and use in the clinical setting. We believe this cost-effective method will offer surgeons who perform partial knee arthroplasty a novel method to obtain the important information gleaned from the valgus stress radiograph and to improve surgical outcomes through the preoperative assessment of the lateral compartment. Additionally, as a quality and safety improvement initiative, we believe this technique will reduce radiographic exposure for those performing these studies, and, because the examination can be carried out by a single technologist, it will significantly improve efficiency in the radiology suite.

Conclusion

We have developed a new method of obtaining the important valgus stress radiograph as part of the workup of patients with medial-compartment osteoarthritis of the knee. The technique can be performed with easily obtainable, commercially available products and is reliable 93.5% of the time. It also adds to the efficiency of the radiology suite and reduces radiographic exposure for technologists.

Isolated brachialis muscle atrophy has been rarely reported. Among the few cases in the literature, 1 was attributed to a presumed compartment syndrome,1 1 to a displaced clavicle fracture,2 and 3 to neuralgic amyotrophy.3,4 We present a case of isolated brachialis muscle atrophy of unknown etiology, the presentation of which is consistent with neuralgic amyotrophy, also known as Parsonage-Turner syndrome or brachial plexitis. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 37-year-old right-handed highway worker presented for evaluation of right-arm muscle atrophy. One year earlier, while lifting heavy bags at work, he felt a painful strain in his right arm, although there was no bruising or swelling. Approximately 4 weeks after this incident, he developed right shoulder pain and began to notice a slight decrease in the muscle mass of his right anterior arm. On evaluation at an outside facility, the physician noted some brachialis muscle atrophy. His shoulder pain was attributed to acromioclavicular joint problems. After an initial trial of physical therapy that did not alleviate this joint pain, an acromioclavicular joint resection was performed, and his pain improved. The brachialis muscle atrophy continued to progress, however. Over the course of the next 6 months, the patient noticed a continually decreasing muscle mass in his right arm, as well as arm fatigue with routine recreational activities. On follow-up, again at an outside institution, the treating physicians noted continued atrophy of the distal arm corresponding to the region of the brachialis musculature. Magnetic resonance imaging showed continuity of the brachialis muscle and tendon, with muscle atrophy. The patient was able to return to work, although with a subjective decrease in right elbow flexion strength.

On presentation at our institution, the patient complained of right arm weakness with heavy use but did not have pain or sensory complaints. His medical history was otherwise unremarkable. Physical examination revealed obvious wasting of the right brachialis muscle, most notable on the lateral aspect of the distal arm (Figures 1, 2A, 2B). His biceps muscle was functioning with full strength and had a normal bulk. He had a normal range of active and passive motion, including full extension and flexion of both elbows, as well as complete pronosupination of the forearms. There was no focal tenderness. Manual muscle testing of both upper extremities was completely normal except for 4/5 flexion strength of the right elbow. Neurovascular examination also revealed normal findings, including intact sensation over the radiolateral forearm. A second magnetic resonance image showed that the brachialis muscle had completely atrophied. Because the clinical examination and imaging studies both indicated isolated brachialis atrophy without deficit elsewhere along the musculocutaneous nerve, electromyography was not performed. The patient was fully functional and working at his usual occupation, and no further intervention was recommended.

Discussion

Isolated wasting of the brachialis muscle is extremely rare with few reports in the literature. Farmer and colleagues¹ reported a case of brachialis atrophy that was presumed to have resulted from exercise-induced chronic compartment syndrome. In that case, the patient developed a prodrome of arm pain followed by brachialis muscle atrophy. This patient was treated with oral anti-inflammatory agents with improvement in pain but without recovery of the brachialis muscle. While this case was attributed to compartment syndrome, it is likely that it represented neuralgic amyotrophy because there was no evidence of elbow flexion contracture, which would have accompanied true necrosis of the brachialis muscle as seen in compartment syndrome. However, acute compartment syndrome of the brachialis muscle after minor trauma has been reported.⁵ In that case, full-scale compartment syndrome was treated with rapid fasciotomy, with complete recovery of the brachialis.

Isolated brachialis atrophy has also been described in the setting of a displaced midshaft clavicle fracture in an elite athlete.² Two fracture fragments were thought to have injured the brachial plexus, separately causing brachialis atrophy and altered sensation over the clavicular head of the deltoid muscle. Atrophy remained 1 year after injury.

Although it had been occasionally reported, the first large series of patients with sporadic neuralgic amyotrophy in the upper extremity was reported by Parsonage and Turner⁶ in 1948. They described 136 patients who developed flaccid paralysis and atrophy of various muscles of the shoulder girdle and/or upper extremity. This was generally preceded by acute pain in the shoulder girdle, often associated with antecedent viral infection, stress, illness, or other precipitating factors.

To our knowledge, there have been 3 other reported cases of neuralgic amyotrophy of the brachialis muscle. Watson and colleagues³ presented 2 patients with nonspecific, neurogenic shoulder pain after which an indolent, progressive atrophy of the brachialis muscle ensued.³ Van Tongel and colleagues⁴ described a more traditional case of Parsonage-Turner syndrome, with bilateral wasting of the shoulder girdle that also exhibited unilateral brachialis atrophy without affecting other muscles in the arm.⁴ Our case, with shoulder pain followed by muscle atrophy, fits the pattern of neuralgic amyotrophy.

Others have similarly described isolated wasting of 1 muscle with the sparing of other muscles with a common innervation. Isolated atrophy of the extensor or flexor pollicis longus has been reported as variants of either posterior or anterior interosseous neuropathy, respectively.^7,8 Nerve fibers in the brachial plexus destined to innervate muscles supplied by the anterior interosseous nerve may be the cause of the motor deficit in cases of anterior interosseous nerve palsy, which seem to be associated with brachial plexitis.⁹

We present a case of isolated brachialis muscle atrophy after a minor trauma that may have resulted from Parsonage-Turner syndrome or a variant of brachial plexitis. The constellation of shoulder and arm pain, with subsequent muscle atrophy, makes this diagnosis likely.

Isolated brachialis muscle atrophy has been rarely reported. Among the few cases in the literature, 1 was attributed to a presumed compartment syndrome,1 1 to a displaced clavicle fracture,2 and 3 to neuralgic amyotrophy.3,4 We present a case of isolated brachialis muscle atrophy of unknown etiology, the presentation of which is consistent with neuralgic amyotrophy, also known as Parsonage-Turner syndrome or brachial plexitis. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 37-year-old right-handed highway worker presented for evaluation of right-arm muscle atrophy. One year earlier, while lifting heavy bags at work, he felt a painful strain in his right arm, although there was no bruising or swelling. Approximately 4 weeks after this incident, he developed right shoulder pain and began to notice a slight decrease in the muscle mass of his right anterior arm. On evaluation at an outside facility, the physician noted some brachialis muscle atrophy. His shoulder pain was attributed to acromioclavicular joint problems. After an initial trial of physical therapy that did not alleviate this joint pain, an acromioclavicular joint resection was performed, and his pain improved. The brachialis muscle atrophy continued to progress, however. Over the course of the next 6 months, the patient noticed a continually decreasing muscle mass in his right arm, as well as arm fatigue with routine recreational activities. On follow-up, again at an outside institution, the treating physicians noted continued atrophy of the distal arm corresponding to the region of the brachialis musculature. Magnetic resonance imaging showed continuity of the brachialis muscle and tendon, with muscle atrophy. The patient was able to return to work, although with a subjective decrease in right elbow flexion strength.

On presentation at our institution, the patient complained of right arm weakness with heavy use but did not have pain or sensory complaints. His medical history was otherwise unremarkable. Physical examination revealed obvious wasting of the right brachialis muscle, most notable on the lateral aspect of the distal arm (Figures 1, 2A, 2B). His biceps muscle was functioning with full strength and had a normal bulk. He had a normal range of active and passive motion, including full extension and flexion of both elbows, as well as complete pronosupination of the forearms. There was no focal tenderness. Manual muscle testing of both upper extremities was completely normal except for 4/5 flexion strength of the right elbow. Neurovascular examination also revealed normal findings, including intact sensation over the radiolateral forearm. A second magnetic resonance image showed that the brachialis muscle had completely atrophied. Because the clinical examination and imaging studies both indicated isolated brachialis atrophy without deficit elsewhere along the musculocutaneous nerve, electromyography was not performed. The patient was fully functional and working at his usual occupation, and no further intervention was recommended.

Discussion

Isolated wasting of the brachialis muscle is extremely rare with few reports in the literature. Farmer and colleagues¹ reported a case of brachialis atrophy that was presumed to have resulted from exercise-induced chronic compartment syndrome. In that case, the patient developed a prodrome of arm pain followed by brachialis muscle atrophy. This patient was treated with oral anti-inflammatory agents with improvement in pain but without recovery of the brachialis muscle. While this case was attributed to compartment syndrome, it is likely that it represented neuralgic amyotrophy because there was no evidence of elbow flexion contracture, which would have accompanied true necrosis of the brachialis muscle as seen in compartment syndrome. However, acute compartment syndrome of the brachialis muscle after minor trauma has been reported.⁵ In that case, full-scale compartment syndrome was treated with rapid fasciotomy, with complete recovery of the brachialis.

Isolated brachialis atrophy has also been described in the setting of a displaced midshaft clavicle fracture in an elite athlete.² Two fracture fragments were thought to have injured the brachial plexus, separately causing brachialis atrophy and altered sensation over the clavicular head of the deltoid muscle. Atrophy remained 1 year after injury.

Although it had been occasionally reported, the first large series of patients with sporadic neuralgic amyotrophy in the upper extremity was reported by Parsonage and Turner⁶ in 1948. They described 136 patients who developed flaccid paralysis and atrophy of various muscles of the shoulder girdle and/or upper extremity. This was generally preceded by acute pain in the shoulder girdle, often associated with antecedent viral infection, stress, illness, or other precipitating factors.

To our knowledge, there have been 3 other reported cases of neuralgic amyotrophy of the brachialis muscle. Watson and colleagues³ presented 2 patients with nonspecific, neurogenic shoulder pain after which an indolent, progressive atrophy of the brachialis muscle ensued.³ Van Tongel and colleagues⁴ described a more traditional case of Parsonage-Turner syndrome, with bilateral wasting of the shoulder girdle that also exhibited unilateral brachialis atrophy without affecting other muscles in the arm.⁴ Our case, with shoulder pain followed by muscle atrophy, fits the pattern of neuralgic amyotrophy.

Others have similarly described isolated wasting of 1 muscle with the sparing of other muscles with a common innervation. Isolated atrophy of the extensor or flexor pollicis longus has been reported as variants of either posterior or anterior interosseous neuropathy, respectively.^7,8 Nerve fibers in the brachial plexus destined to innervate muscles supplied by the anterior interosseous nerve may be the cause of the motor deficit in cases of anterior interosseous nerve palsy, which seem to be associated with brachial plexitis.⁹

We present a case of isolated brachialis muscle atrophy after a minor trauma that may have resulted from Parsonage-Turner syndrome or a variant of brachial plexitis. The constellation of shoulder and arm pain, with subsequent muscle atrophy, makes this diagnosis likely.

Isolated brachialis muscle atrophy has been rarely reported. Among the few cases in the literature, 1 was attributed to a presumed compartment syndrome,1 1 to a displaced clavicle fracture,2 and 3 to neuralgic amyotrophy.3,4 We present a case of isolated brachialis muscle atrophy of unknown etiology, the presentation of which is consistent with neuralgic amyotrophy, also known as Parsonage-Turner syndrome or brachial plexitis. The patient provided written informed consent for print and electronic publication of this case report.

Case Report

A 37-year-old right-handed highway worker presented for evaluation of right-arm muscle atrophy. One year earlier, while lifting heavy bags at work, he felt a painful strain in his right arm, although there was no bruising or swelling. Approximately 4 weeks after this incident, he developed right shoulder pain and began to notice a slight decrease in the muscle mass of his right anterior arm. On evaluation at an outside facility, the physician noted some brachialis muscle atrophy. His shoulder pain was attributed to acromioclavicular joint problems. After an initial trial of physical therapy that did not alleviate this joint pain, an acromioclavicular joint resection was performed, and his pain improved. The brachialis muscle atrophy continued to progress, however. Over the course of the next 6 months, the patient noticed a continually decreasing muscle mass in his right arm, as well as arm fatigue with routine recreational activities. On follow-up, again at an outside institution, the treating physicians noted continued atrophy of the distal arm corresponding to the region of the brachialis musculature. Magnetic resonance imaging showed continuity of the brachialis muscle and tendon, with muscle atrophy. The patient was able to return to work, although with a subjective decrease in right elbow flexion strength.

On presentation at our institution, the patient complained of right arm weakness with heavy use but did not have pain or sensory complaints. His medical history was otherwise unremarkable. Physical examination revealed obvious wasting of the right brachialis muscle, most notable on the lateral aspect of the distal arm (Figures 1, 2A, 2B). His biceps muscle was functioning with full strength and had a normal bulk. He had a normal range of active and passive motion, including full extension and flexion of both elbows, as well as complete pronosupination of the forearms. There was no focal tenderness. Manual muscle testing of both upper extremities was completely normal except for 4/5 flexion strength of the right elbow. Neurovascular examination also revealed normal findings, including intact sensation over the radiolateral forearm. A second magnetic resonance image showed that the brachialis muscle had completely atrophied. Because the clinical examination and imaging studies both indicated isolated brachialis atrophy without deficit elsewhere along the musculocutaneous nerve, electromyography was not performed. The patient was fully functional and working at his usual occupation, and no further intervention was recommended.

Discussion

Isolated wasting of the brachialis muscle is extremely rare with few reports in the literature. Farmer and colleagues¹ reported a case of brachialis atrophy that was presumed to have resulted from exercise-induced chronic compartment syndrome. In that case, the patient developed a prodrome of arm pain followed by brachialis muscle atrophy. This patient was treated with oral anti-inflammatory agents with improvement in pain but without recovery of the brachialis muscle. While this case was attributed to compartment syndrome, it is likely that it represented neuralgic amyotrophy because there was no evidence of elbow flexion contracture, which would have accompanied true necrosis of the brachialis muscle as seen in compartment syndrome. However, acute compartment syndrome of the brachialis muscle after minor trauma has been reported.⁵ In that case, full-scale compartment syndrome was treated with rapid fasciotomy, with complete recovery of the brachialis.

Isolated brachialis atrophy has also been described in the setting of a displaced midshaft clavicle fracture in an elite athlete.² Two fracture fragments were thought to have injured the brachial plexus, separately causing brachialis atrophy and altered sensation over the clavicular head of the deltoid muscle. Atrophy remained 1 year after injury.

Although it had been occasionally reported, the first large series of patients with sporadic neuralgic amyotrophy in the upper extremity was reported by Parsonage and Turner⁶ in 1948. They described 136 patients who developed flaccid paralysis and atrophy of various muscles of the shoulder girdle and/or upper extremity. This was generally preceded by acute pain in the shoulder girdle, often associated with antecedent viral infection, stress, illness, or other precipitating factors.

To our knowledge, there have been 3 other reported cases of neuralgic amyotrophy of the brachialis muscle. Watson and colleagues³ presented 2 patients with nonspecific, neurogenic shoulder pain after which an indolent, progressive atrophy of the brachialis muscle ensued.³ Van Tongel and colleagues⁴ described a more traditional case of Parsonage-Turner syndrome, with bilateral wasting of the shoulder girdle that also exhibited unilateral brachialis atrophy without affecting other muscles in the arm.⁴ Our case, with shoulder pain followed by muscle atrophy, fits the pattern of neuralgic amyotrophy.

Others have similarly described isolated wasting of 1 muscle with the sparing of other muscles with a common innervation. Isolated atrophy of the extensor or flexor pollicis longus has been reported as variants of either posterior or anterior interosseous neuropathy, respectively.^7,8 Nerve fibers in the brachial plexus destined to innervate muscles supplied by the anterior interosseous nerve may be the cause of the motor deficit in cases of anterior interosseous nerve palsy, which seem to be associated with brachial plexitis.⁹

We present a case of isolated brachialis muscle atrophy after a minor trauma that may have resulted from Parsonage-Turner syndrome or a variant of brachial plexitis. The constellation of shoulder and arm pain, with subsequent muscle atrophy, makes this diagnosis likely.