Gregory P. Nicholson, MD

ABSTRACT

An increasing interest focuses on the rates and risk factors for hospital readmission. However, little is known regarding the readmission following total shoulder arthroplasty (TSA). This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA. Patients undergoing TSA (anatomic or reverse) as part of the American College of Surgeons National Surgical Quality Improvement Program in 2011 to 2013 were identified. The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. Using multivariate regression, demographic and comorbidity factors were tested for independent association with readmission. Finally, the reasons for readmission were characterized. A total of 3627 patients were identified. Among the admitted patients, 93 (2.56%) were readmitted within 30 days of surgery. The independent risk factors for readmission included old age (for age 60-69 years, relative risk [RR] = 1.6; for age 70-79 years, RR = 2.3; for age ≥80 years, RR = 23.1; P = .042), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission comprised pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%). Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at higher risk for readmission and should be counseled and monitored accordingly.

Continue to: Total shoulder arthroplasty...

Total shoulder arthroplasty (TSA) is performed with increasing frequency in the United States and is considered to be cost-effective.^1-4 Following the procedure, patients generally achieve shoulder function and pain relief.^5-8 Despite the success of the procedure, the growing literature on TSA has also reported rates of complications between 3.6% and 25% of the treated patients.^9-16

In recent years, an increasing interest has focused on the rates and risk factors for unplanned hospital readmissions; these variables may not only reflect the quality of patient care but also result in considerable costs to the healthcare system. For instance, among Medicare patients, readmissions within 30 days of discharge occur in almost 20% of cases, costing $17.4 billion per year.¹⁷ Readmission rates increasingly factor into hospital performance metrics and reimbursement, including the Hospital Readmissions Reduction Program of the Patient Protection and Affordable Care Act that reduces Centers for Medicare and Medicaid Services payments to hospitals with high 30-day readmission rates.¹⁸

To date, only a few studies have evaluated readmission following TSA, with 30- to 90-day readmission rates ranging from 4.5% to 7.3%.^19-23 These studies comprised single institution series^20,22 and analyses of administrative databases.^19,21,23 Most studies have shown that readmission occurs more often for medical than surgical reasons, with surgical reasons most commonly including infection and dislocation.^19-23 However, only limited analyses have been conducted regarding risk factors for readmission.^21,23 To date and to our knowledge, no study has investigated reasons for readmission following TSA using nationwide data.

This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA in the United States using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

METHODS

DATA SOURCE

The NSQIP database was utilized to address the study purpose. NSQIP is a nationwide prospective surgical registry established by the American College of Surgeons and reports data from academic and community hospitals across the United States.²⁴ Patients undertaking surgery at these centers are followed by the surgical clinical reviewers at the participating NSQIP sites prospectively for 30 days following the procedure to record complications including readmission. Preoperative and surgical data, such as demographics, medical comorbid diseases, and operative time, are also included. Previous studies have analyzed the complications of various orthopedic surgeries using the NSQIP data.^14,16,25-30

DATA COLLECTION

We retrospectively identified from NSQIP the patients who underwent primary TSA (anatomic or reverse) in 2013 to 2014. The timeframe 2013 to 2014 was used because NSQIP only began recording reasons for readmission in 2013. The inclusion criteria were as follows: Current Procedural Terminology (CPT) code for TSA (23472); preoperative diagnosis according to the International Classification of Diseases, Ninth Revision (ICD-9) codes 714.0, 715.11, 715.31, 715.91, 715.21, 715.89, 716.xx 718.xx, 719.xx, 726.x, 727.xx, and 733.41 (where x is a wild card digit); and no missing demographic, comorbidity, or outcome data. Anatomic and reverse TSA were analyzed together because they share the same CPT code, and the NSQIP database prevents searching by the ICD-9 procedure code.

The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. The reasons for readmission in this 30-day period were only available in 2013 and were determined using the ICD-9 diagnosis codes. Patient demographics were recorded for use in identifying potential risk factors for readmission; the demographic data included sex, age, smoking status, body mass index (BMI), and comorbidities, including end-stage renal disease, dyspnea on exertion, congestive heart failure, diabetes mellitus, hypertension, and chronic obstructive pulmonary disease (COPD).

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were performed using Stata version 13.1 (StataCorp). First, using bivariate and multivariate regression, demographic and comorbidity factors were tested for independent association with readmission to the hospital within 30 days of surgery. Second, among the readmitted patients, the reasons for readmission were tabulated. Of note, the reasons for readmission were only documented for the procedures performed in 2013. All tests were 2-tailed and conducted at an α level of 0.05.

RESTULTS

A total of 3627 TSA patients were identified. The mean age (± standard deviation) was 69.4 ± 9.5 years, 55.8% of patients were female, and mean BMI was 30.1 ± 7.0 years. Table 1 provides the additional demographic data. Of the 3627 included patients, 93 (2.56%) were readmitted within 30 days of surgery. The 95% confidence interval for the estimated rate of readmission reached 2.05% to 3.08%.

Table 1. Patient Population

Abbreviation: COPD, chronic obstructive pulmonary disease.

In the bivariate analyses (Table 2), the following factors were positively associated readmission: older age (60-69 years, relative risk [RR] = 1.6; 70-79 years, RR = 2.2; ≥80 years, RR = 3.3; P = .011), dependent functional status (RR = 2.9, P = .008), and anemia (RR = 2.2, P < .001).

Table 2. Bivariate Analysis of Risk Factors for Readmission

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

In the multivariate analyses (Table 3), the following factors were independent risk factors for readmission: older age (60-69 years, RR = 1.6; 70-79 years, RR = 2.3; ≥80 years, RR = 3.1; P =.027), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). Interestingly, readmission showed no independent association with diabetes, dyspnea on exertion, BMI, COPD, hypertension, or current smoking status (P > .05 for each).

Table 3. Independent Risk Factors for Readmission on Multivariate Analysis

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

Continue to: Table 4...

The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission included pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%) (Table 4).

Table 4. Reasons for Readmission

DISCUSSION

Our analysis of 3042 TSAs from the NSQIP database suggests that unplanned readmission to the hospital occurs following about 1 in 40 cases of TSA. The study also suggests that the most common reasons for readmission encompass pneumonia, dislocation, pulmonary embolism, and surgical site infection. Old age, male sex, anemia, and dependent functional status serve as risk factors for readmission, and patients with such factors should be counseled and monitored accordingly.

In recent years, an increasing emphasis has centered on reducing rates of hospital readmission, with programs such as the Hospital Readmissions Reduction Program of the Affordable Care Act cutting reimbursements for hospitals with high 30-day readmission rates.^17,18 To date, only a few studies have evaluated the reasons for readmission and readmission rates for TSA.^19-23 Initial reports consisted of single-institution TSA registry reviews. For example, Mahoney and colleagues²⁰ retrospectively evaluated shoulder arthroplasty procedures at their institution to document the readmission rates, finding a 5.9% readmission rate at 30 days. Readmission occurred more frequently in the first 30 days following discharge than in the 30- to 90-day period, with the most common reasons for readmission including medical complications, infection, and dislocation. Streubel and colleagues²² evaluated reoperation rates from their institution’s TSA registry, finding a 0.6% reoperation rate for primary TSA at 30 days and 1.5% for revision TSA. Instability and infection were the most common indications for reoperation. Our findings confirm these single-institution results and demonstrate their application to a nationwide sample of TSA, not just to high-volume academic centers. We similarly observed that dislocation, surgical site infection, and medical complications (mostly pneumonia and pulmonary embolism) were common causes of readmission, and that the 30-day readmission rate was about 1 in 40.

Several authors have since used statewide databases to analyze and determine risk factors for readmission following TSA. Lyman and colleagues¹⁹ used the New York State Database to show that higher hospital TSA surgical volume was associated with a lower rate of readmission when age and comorbidities were controlled for in a multivariate model. Old age was also associated with an increased readmission rate in their multivariate analysis, but comorbidities (as measured by the Charlson comorbidity index) presented a nonsignificant associative trend. These authors opted not to determine specific causes of readmission. Schairer and colleagues²¹ used State Inpatient Databases from 7 states, finding a 90-day readmission rate of 7.3%, 82% of which were due to medical complications and 18% of which were due to surgical complications (mostly infection and dislocation). Their multivariate regression revealed that male sex, reverse TSA, Medicaid insurance, patients discharged to inpatient rehabilitation or nursing facilities, medical comorbidities, and low-volume TSA hospitals were associated with readmission. Zhang and colleagues²³ used the same source to show that the 90-day readmission rate reached 14% for surgically treated proximal humerus fractures and higher for patients who underwent open reduction internal fixation, were female, were African American, were discharged to a nursing facility, possessed Medicaid insurance, or experienced medical comorbidities. Most recently, Basques and colleagues³¹ analyzed 1505 TSA cases from 2011 and 2012 in the NSQIP database, finding a 3.3% rate of readmission, with heart disease and hypertension as risk factors for readmission. Although the limitations of the NSQIP database prevented us from analyzing surgeon and hospital TSA volume or reverse vs anatomic TSA, our results confirm that the findings from statewide database studies apply to the United States nationwide NSQIP database. Old patient age, male sex, and medical comorbidities (anemia and dependent functional status) are independent risk factors for TSA readmission. We identified pneumonia, dislocation, pulmonary embolism, and surgical site infection as the most common reasons for readmission.

This study features several limitations that should be considered when interpreting the results. Anatomic and reverse TSA share a CPT code and were not separated using NSQIP data. A number of studies have reported that reverse TSA may place patients at higher risk for readmission;^20,21 however, confounding by other patient factors could play a role in this finding. The 30-day timeframe for readmission is another potential limitation; however, this timeframe is frequently used in other studies and is the relevant timeframe for the reduced reimbursement penalties from the Hospital Readmissions Reduction Program of the Affordable Care Act.¹⁸ Furthermore, the NSQIP database contains no information on surgeon or hospital TSA volume, which is a result of safeguards for patient and provider privacy. Additionally, readmission data were only available for 2011 to 2013, with causes of readmission only present in 2013. Although provided with such current information, we cannot analyze readmission trends over time, such as in response to the Affordable Care Act of 2010. Finally, although NSQIP surgical clinical reviewers strive to identify readmissions to other hospitals during their reviews of outpatient medical records, proportions of these readmissions are possibly missed. Therefore, our 30-day readmission rate may slightly underestimate the true rate.

Despite these limitations, the NSQIP database offers a unique opportunity to examine risk factors and reasons for readmission following TSA. The prior literature on readmission following TSA stemmed either from limited samples or administrative data, which feature known limitations.³² By utilizing a large, prospective, non-administrative, nationwide sample, our findings are probably both more reliable and generalizable to the country as a whole.

CONCLUSION

Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at a higher risk for readmission and should be counseled and monitored accordingly.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

An increasing interest focuses on the rates and risk factors for hospital readmission. However, little is known regarding the readmission following total shoulder arthroplasty (TSA). This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA. Patients undergoing TSA (anatomic or reverse) as part of the American College of Surgeons National Surgical Quality Improvement Program in 2011 to 2013 were identified. The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. Using multivariate regression, demographic and comorbidity factors were tested for independent association with readmission. Finally, the reasons for readmission were characterized. A total of 3627 patients were identified. Among the admitted patients, 93 (2.56%) were readmitted within 30 days of surgery. The independent risk factors for readmission included old age (for age 60-69 years, relative risk [RR] = 1.6; for age 70-79 years, RR = 2.3; for age ≥80 years, RR = 23.1; P = .042), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission comprised pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%). Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at higher risk for readmission and should be counseled and monitored accordingly.

Continue to: Total shoulder arthroplasty...

Total shoulder arthroplasty (TSA) is performed with increasing frequency in the United States and is considered to be cost-effective.^1-4 Following the procedure, patients generally achieve shoulder function and pain relief.^5-8 Despite the success of the procedure, the growing literature on TSA has also reported rates of complications between 3.6% and 25% of the treated patients.^9-16

In recent years, an increasing interest has focused on the rates and risk factors for unplanned hospital readmissions; these variables may not only reflect the quality of patient care but also result in considerable costs to the healthcare system. For instance, among Medicare patients, readmissions within 30 days of discharge occur in almost 20% of cases, costing $17.4 billion per year.¹⁷ Readmission rates increasingly factor into hospital performance metrics and reimbursement, including the Hospital Readmissions Reduction Program of the Patient Protection and Affordable Care Act that reduces Centers for Medicare and Medicaid Services payments to hospitals with high 30-day readmission rates.¹⁸

To date, only a few studies have evaluated readmission following TSA, with 30- to 90-day readmission rates ranging from 4.5% to 7.3%.^19-23 These studies comprised single institution series^20,22 and analyses of administrative databases.^19,21,23 Most studies have shown that readmission occurs more often for medical than surgical reasons, with surgical reasons most commonly including infection and dislocation.^19-23 However, only limited analyses have been conducted regarding risk factors for readmission.^21,23 To date and to our knowledge, no study has investigated reasons for readmission following TSA using nationwide data.

This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA in the United States using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

METHODS

DATA SOURCE

The NSQIP database was utilized to address the study purpose. NSQIP is a nationwide prospective surgical registry established by the American College of Surgeons and reports data from academic and community hospitals across the United States.²⁴ Patients undertaking surgery at these centers are followed by the surgical clinical reviewers at the participating NSQIP sites prospectively for 30 days following the procedure to record complications including readmission. Preoperative and surgical data, such as demographics, medical comorbid diseases, and operative time, are also included. Previous studies have analyzed the complications of various orthopedic surgeries using the NSQIP data.^14,16,25-30

DATA COLLECTION

We retrospectively identified from NSQIP the patients who underwent primary TSA (anatomic or reverse) in 2013 to 2014. The timeframe 2013 to 2014 was used because NSQIP only began recording reasons for readmission in 2013. The inclusion criteria were as follows: Current Procedural Terminology (CPT) code for TSA (23472); preoperative diagnosis according to the International Classification of Diseases, Ninth Revision (ICD-9) codes 714.0, 715.11, 715.31, 715.91, 715.21, 715.89, 716.xx 718.xx, 719.xx, 726.x, 727.xx, and 733.41 (where x is a wild card digit); and no missing demographic, comorbidity, or outcome data. Anatomic and reverse TSA were analyzed together because they share the same CPT code, and the NSQIP database prevents searching by the ICD-9 procedure code.

The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. The reasons for readmission in this 30-day period were only available in 2013 and were determined using the ICD-9 diagnosis codes. Patient demographics were recorded for use in identifying potential risk factors for readmission; the demographic data included sex, age, smoking status, body mass index (BMI), and comorbidities, including end-stage renal disease, dyspnea on exertion, congestive heart failure, diabetes mellitus, hypertension, and chronic obstructive pulmonary disease (COPD).

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were performed using Stata version 13.1 (StataCorp). First, using bivariate and multivariate regression, demographic and comorbidity factors were tested for independent association with readmission to the hospital within 30 days of surgery. Second, among the readmitted patients, the reasons for readmission were tabulated. Of note, the reasons for readmission were only documented for the procedures performed in 2013. All tests were 2-tailed and conducted at an α level of 0.05.

RESTULTS

A total of 3627 TSA patients were identified. The mean age (± standard deviation) was 69.4 ± 9.5 years, 55.8% of patients were female, and mean BMI was 30.1 ± 7.0 years. Table 1 provides the additional demographic data. Of the 3627 included patients, 93 (2.56%) were readmitted within 30 days of surgery. The 95% confidence interval for the estimated rate of readmission reached 2.05% to 3.08%.

Table 1. Patient Population

Abbreviation: COPD, chronic obstructive pulmonary disease.

In the bivariate analyses (Table 2), the following factors were positively associated readmission: older age (60-69 years, relative risk [RR] = 1.6; 70-79 years, RR = 2.2; ≥80 years, RR = 3.3; P = .011), dependent functional status (RR = 2.9, P = .008), and anemia (RR = 2.2, P < .001).

Table 2. Bivariate Analysis of Risk Factors for Readmission

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

In the multivariate analyses (Table 3), the following factors were independent risk factors for readmission: older age (60-69 years, RR = 1.6; 70-79 years, RR = 2.3; ≥80 years, RR = 3.1; P =.027), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). Interestingly, readmission showed no independent association with diabetes, dyspnea on exertion, BMI, COPD, hypertension, or current smoking status (P > .05 for each).

Table 3. Independent Risk Factors for Readmission on Multivariate Analysis

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

Continue to: Table 4...

The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission included pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%) (Table 4).

Table 4. Reasons for Readmission

DISCUSSION

Our analysis of 3042 TSAs from the NSQIP database suggests that unplanned readmission to the hospital occurs following about 1 in 40 cases of TSA. The study also suggests that the most common reasons for readmission encompass pneumonia, dislocation, pulmonary embolism, and surgical site infection. Old age, male sex, anemia, and dependent functional status serve as risk factors for readmission, and patients with such factors should be counseled and monitored accordingly.

In recent years, an increasing emphasis has centered on reducing rates of hospital readmission, with programs such as the Hospital Readmissions Reduction Program of the Affordable Care Act cutting reimbursements for hospitals with high 30-day readmission rates.^17,18 To date, only a few studies have evaluated the reasons for readmission and readmission rates for TSA.^19-23 Initial reports consisted of single-institution TSA registry reviews. For example, Mahoney and colleagues²⁰ retrospectively evaluated shoulder arthroplasty procedures at their institution to document the readmission rates, finding a 5.9% readmission rate at 30 days. Readmission occurred more frequently in the first 30 days following discharge than in the 30- to 90-day period, with the most common reasons for readmission including medical complications, infection, and dislocation. Streubel and colleagues²² evaluated reoperation rates from their institution’s TSA registry, finding a 0.6% reoperation rate for primary TSA at 30 days and 1.5% for revision TSA. Instability and infection were the most common indications for reoperation. Our findings confirm these single-institution results and demonstrate their application to a nationwide sample of TSA, not just to high-volume academic centers. We similarly observed that dislocation, surgical site infection, and medical complications (mostly pneumonia and pulmonary embolism) were common causes of readmission, and that the 30-day readmission rate was about 1 in 40.

Several authors have since used statewide databases to analyze and determine risk factors for readmission following TSA. Lyman and colleagues¹⁹ used the New York State Database to show that higher hospital TSA surgical volume was associated with a lower rate of readmission when age and comorbidities were controlled for in a multivariate model. Old age was also associated with an increased readmission rate in their multivariate analysis, but comorbidities (as measured by the Charlson comorbidity index) presented a nonsignificant associative trend. These authors opted not to determine specific causes of readmission. Schairer and colleagues²¹ used State Inpatient Databases from 7 states, finding a 90-day readmission rate of 7.3%, 82% of which were due to medical complications and 18% of which were due to surgical complications (mostly infection and dislocation). Their multivariate regression revealed that male sex, reverse TSA, Medicaid insurance, patients discharged to inpatient rehabilitation or nursing facilities, medical comorbidities, and low-volume TSA hospitals were associated with readmission. Zhang and colleagues²³ used the same source to show that the 90-day readmission rate reached 14% for surgically treated proximal humerus fractures and higher for patients who underwent open reduction internal fixation, were female, were African American, were discharged to a nursing facility, possessed Medicaid insurance, or experienced medical comorbidities. Most recently, Basques and colleagues³¹ analyzed 1505 TSA cases from 2011 and 2012 in the NSQIP database, finding a 3.3% rate of readmission, with heart disease and hypertension as risk factors for readmission. Although the limitations of the NSQIP database prevented us from analyzing surgeon and hospital TSA volume or reverse vs anatomic TSA, our results confirm that the findings from statewide database studies apply to the United States nationwide NSQIP database. Old patient age, male sex, and medical comorbidities (anemia and dependent functional status) are independent risk factors for TSA readmission. We identified pneumonia, dislocation, pulmonary embolism, and surgical site infection as the most common reasons for readmission.

This study features several limitations that should be considered when interpreting the results. Anatomic and reverse TSA share a CPT code and were not separated using NSQIP data. A number of studies have reported that reverse TSA may place patients at higher risk for readmission;^20,21 however, confounding by other patient factors could play a role in this finding. The 30-day timeframe for readmission is another potential limitation; however, this timeframe is frequently used in other studies and is the relevant timeframe for the reduced reimbursement penalties from the Hospital Readmissions Reduction Program of the Affordable Care Act.¹⁸ Furthermore, the NSQIP database contains no information on surgeon or hospital TSA volume, which is a result of safeguards for patient and provider privacy. Additionally, readmission data were only available for 2011 to 2013, with causes of readmission only present in 2013. Although provided with such current information, we cannot analyze readmission trends over time, such as in response to the Affordable Care Act of 2010. Finally, although NSQIP surgical clinical reviewers strive to identify readmissions to other hospitals during their reviews of outpatient medical records, proportions of these readmissions are possibly missed. Therefore, our 30-day readmission rate may slightly underestimate the true rate.

Despite these limitations, the NSQIP database offers a unique opportunity to examine risk factors and reasons for readmission following TSA. The prior literature on readmission following TSA stemmed either from limited samples or administrative data, which feature known limitations.³² By utilizing a large, prospective, non-administrative, nationwide sample, our findings are probably both more reliable and generalizable to the country as a whole.

CONCLUSION

Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at a higher risk for readmission and should be counseled and monitored accordingly.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

An increasing interest focuses on the rates and risk factors for hospital readmission. However, little is known regarding the readmission following total shoulder arthroplasty (TSA). This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA. Patients undergoing TSA (anatomic or reverse) as part of the American College of Surgeons National Surgical Quality Improvement Program in 2011 to 2013 were identified. The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. Using multivariate regression, demographic and comorbidity factors were tested for independent association with readmission. Finally, the reasons for readmission were characterized. A total of 3627 patients were identified. Among the admitted patients, 93 (2.56%) were readmitted within 30 days of surgery. The independent risk factors for readmission included old age (for age 60-69 years, relative risk [RR] = 1.6; for age 70-79 years, RR = 2.3; for age ≥80 years, RR = 23.1; P = .042), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission comprised pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%). Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at higher risk for readmission and should be counseled and monitored accordingly.

Continue to: Total shoulder arthroplasty...

Total shoulder arthroplasty (TSA) is performed with increasing frequency in the United States and is considered to be cost-effective.^1-4 Following the procedure, patients generally achieve shoulder function and pain relief.^5-8 Despite the success of the procedure, the growing literature on TSA has also reported rates of complications between 3.6% and 25% of the treated patients.^9-16

In recent years, an increasing interest has focused on the rates and risk factors for unplanned hospital readmissions; these variables may not only reflect the quality of patient care but also result in considerable costs to the healthcare system. For instance, among Medicare patients, readmissions within 30 days of discharge occur in almost 20% of cases, costing $17.4 billion per year.¹⁷ Readmission rates increasingly factor into hospital performance metrics and reimbursement, including the Hospital Readmissions Reduction Program of the Patient Protection and Affordable Care Act that reduces Centers for Medicare and Medicaid Services payments to hospitals with high 30-day readmission rates.¹⁸

To date, only a few studies have evaluated readmission following TSA, with 30- to 90-day readmission rates ranging from 4.5% to 7.3%.^19-23 These studies comprised single institution series^20,22 and analyses of administrative databases.^19,21,23 Most studies have shown that readmission occurs more often for medical than surgical reasons, with surgical reasons most commonly including infection and dislocation.^19-23 However, only limited analyses have been conducted regarding risk factors for readmission.^21,23 To date and to our knowledge, no study has investigated reasons for readmission following TSA using nationwide data.

This study aims to determine the rates, risk factors, and reasons for hospital readmission following primary TSA in the United States using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database.

METHODS

DATA SOURCE

The NSQIP database was utilized to address the study purpose. NSQIP is a nationwide prospective surgical registry established by the American College of Surgeons and reports data from academic and community hospitals across the United States.²⁴ Patients undertaking surgery at these centers are followed by the surgical clinical reviewers at the participating NSQIP sites prospectively for 30 days following the procedure to record complications including readmission. Preoperative and surgical data, such as demographics, medical comorbid diseases, and operative time, are also included. Previous studies have analyzed the complications of various orthopedic surgeries using the NSQIP data.^14,16,25-30

DATA COLLECTION

We retrospectively identified from NSQIP the patients who underwent primary TSA (anatomic or reverse) in 2013 to 2014. The timeframe 2013 to 2014 was used because NSQIP only began recording reasons for readmission in 2013. The inclusion criteria were as follows: Current Procedural Terminology (CPT) code for TSA (23472); preoperative diagnosis according to the International Classification of Diseases, Ninth Revision (ICD-9) codes 714.0, 715.11, 715.31, 715.91, 715.21, 715.89, 716.xx 718.xx, 719.xx, 726.x, 727.xx, and 733.41 (where x is a wild card digit); and no missing demographic, comorbidity, or outcome data. Anatomic and reverse TSA were analyzed together because they share the same CPT code, and the NSQIP database prevents searching by the ICD-9 procedure code.

The rate of unplanned readmission to the hospital within 30 postoperative days was characterized. The reasons for readmission in this 30-day period were only available in 2013 and were determined using the ICD-9 diagnosis codes. Patient demographics were recorded for use in identifying potential risk factors for readmission; the demographic data included sex, age, smoking status, body mass index (BMI), and comorbidities, including end-stage renal disease, dyspnea on exertion, congestive heart failure, diabetes mellitus, hypertension, and chronic obstructive pulmonary disease (COPD).

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were performed using Stata version 13.1 (StataCorp). First, using bivariate and multivariate regression, demographic and comorbidity factors were tested for independent association with readmission to the hospital within 30 days of surgery. Second, among the readmitted patients, the reasons for readmission were tabulated. Of note, the reasons for readmission were only documented for the procedures performed in 2013. All tests were 2-tailed and conducted at an α level of 0.05.

RESTULTS

A total of 3627 TSA patients were identified. The mean age (± standard deviation) was 69.4 ± 9.5 years, 55.8% of patients were female, and mean BMI was 30.1 ± 7.0 years. Table 1 provides the additional demographic data. Of the 3627 included patients, 93 (2.56%) were readmitted within 30 days of surgery. The 95% confidence interval for the estimated rate of readmission reached 2.05% to 3.08%.

Table 1. Patient Population

Abbreviation: COPD, chronic obstructive pulmonary disease.

In the bivariate analyses (Table 2), the following factors were positively associated readmission: older age (60-69 years, relative risk [RR] = 1.6; 70-79 years, RR = 2.2; ≥80 years, RR = 3.3; P = .011), dependent functional status (RR = 2.9, P = .008), and anemia (RR = 2.2, P < .001).

Table 2. Bivariate Analysis of Risk Factors for Readmission

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

In the multivariate analyses (Table 3), the following factors were independent risk factors for readmission: older age (60-69 years, RR = 1.6; 70-79 years, RR = 2.3; ≥80 years, RR = 3.1; P =.027), male sex (RR = 1.6, P = .025), anemia (RR = 1.9, P = .005), and dependent functional status (RR = 2.8, P = .012). Interestingly, readmission showed no independent association with diabetes, dyspnea on exertion, BMI, COPD, hypertension, or current smoking status (P > .05 for each).

Table 3. Independent Risk Factors for Readmission on Multivariate Analysis

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; RR, relative risk.

Continue to: Table 4...

The reasons for readmission were available for 84 of the 93 readmitted patients. The most common reasons for readmission included pneumonia (14 cases, 16.7%), dislocation (7 cases, 8.3%), pulmonary embolism (7 cases, 8.3%), and surgical site infection (6 cases, 7.1%) (Table 4).

Table 4. Reasons for Readmission

DISCUSSION

Our analysis of 3042 TSAs from the NSQIP database suggests that unplanned readmission to the hospital occurs following about 1 in 40 cases of TSA. The study also suggests that the most common reasons for readmission encompass pneumonia, dislocation, pulmonary embolism, and surgical site infection. Old age, male sex, anemia, and dependent functional status serve as risk factors for readmission, and patients with such factors should be counseled and monitored accordingly.

In recent years, an increasing emphasis has centered on reducing rates of hospital readmission, with programs such as the Hospital Readmissions Reduction Program of the Affordable Care Act cutting reimbursements for hospitals with high 30-day readmission rates.^17,18 To date, only a few studies have evaluated the reasons for readmission and readmission rates for TSA.^19-23 Initial reports consisted of single-institution TSA registry reviews. For example, Mahoney and colleagues²⁰ retrospectively evaluated shoulder arthroplasty procedures at their institution to document the readmission rates, finding a 5.9% readmission rate at 30 days. Readmission occurred more frequently in the first 30 days following discharge than in the 30- to 90-day period, with the most common reasons for readmission including medical complications, infection, and dislocation. Streubel and colleagues²² evaluated reoperation rates from their institution’s TSA registry, finding a 0.6% reoperation rate for primary TSA at 30 days and 1.5% for revision TSA. Instability and infection were the most common indications for reoperation. Our findings confirm these single-institution results and demonstrate their application to a nationwide sample of TSA, not just to high-volume academic centers. We similarly observed that dislocation, surgical site infection, and medical complications (mostly pneumonia and pulmonary embolism) were common causes of readmission, and that the 30-day readmission rate was about 1 in 40.

Several authors have since used statewide databases to analyze and determine risk factors for readmission following TSA. Lyman and colleagues¹⁹ used the New York State Database to show that higher hospital TSA surgical volume was associated with a lower rate of readmission when age and comorbidities were controlled for in a multivariate model. Old age was also associated with an increased readmission rate in their multivariate analysis, but comorbidities (as measured by the Charlson comorbidity index) presented a nonsignificant associative trend. These authors opted not to determine specific causes of readmission. Schairer and colleagues²¹ used State Inpatient Databases from 7 states, finding a 90-day readmission rate of 7.3%, 82% of which were due to medical complications and 18% of which were due to surgical complications (mostly infection and dislocation). Their multivariate regression revealed that male sex, reverse TSA, Medicaid insurance, patients discharged to inpatient rehabilitation or nursing facilities, medical comorbidities, and low-volume TSA hospitals were associated with readmission. Zhang and colleagues²³ used the same source to show that the 90-day readmission rate reached 14% for surgically treated proximal humerus fractures and higher for patients who underwent open reduction internal fixation, were female, were African American, were discharged to a nursing facility, possessed Medicaid insurance, or experienced medical comorbidities. Most recently, Basques and colleagues³¹ analyzed 1505 TSA cases from 2011 and 2012 in the NSQIP database, finding a 3.3% rate of readmission, with heart disease and hypertension as risk factors for readmission. Although the limitations of the NSQIP database prevented us from analyzing surgeon and hospital TSA volume or reverse vs anatomic TSA, our results confirm that the findings from statewide database studies apply to the United States nationwide NSQIP database. Old patient age, male sex, and medical comorbidities (anemia and dependent functional status) are independent risk factors for TSA readmission. We identified pneumonia, dislocation, pulmonary embolism, and surgical site infection as the most common reasons for readmission.

This study features several limitations that should be considered when interpreting the results. Anatomic and reverse TSA share a CPT code and were not separated using NSQIP data. A number of studies have reported that reverse TSA may place patients at higher risk for readmission;^20,21 however, confounding by other patient factors could play a role in this finding. The 30-day timeframe for readmission is another potential limitation; however, this timeframe is frequently used in other studies and is the relevant timeframe for the reduced reimbursement penalties from the Hospital Readmissions Reduction Program of the Affordable Care Act.¹⁸ Furthermore, the NSQIP database contains no information on surgeon or hospital TSA volume, which is a result of safeguards for patient and provider privacy. Additionally, readmission data were only available for 2011 to 2013, with causes of readmission only present in 2013. Although provided with such current information, we cannot analyze readmission trends over time, such as in response to the Affordable Care Act of 2010. Finally, although NSQIP surgical clinical reviewers strive to identify readmissions to other hospitals during their reviews of outpatient medical records, proportions of these readmissions are possibly missed. Therefore, our 30-day readmission rate may slightly underestimate the true rate.

Despite these limitations, the NSQIP database offers a unique opportunity to examine risk factors and reasons for readmission following TSA. The prior literature on readmission following TSA stemmed either from limited samples or administrative data, which feature known limitations.³² By utilizing a large, prospective, non-administrative, nationwide sample, our findings are probably both more reliable and generalizable to the country as a whole.

CONCLUSION

Unplanned readmission occurs following about 1 in 40 cases of TSA. The most common causes of readmission include pneumonia, dislocation, pulmonary embolism, and surgical site infection. Patients with old age, male sex, anemia, and dependent functional status are at a higher risk for readmission and should be counseled and monitored accordingly.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

It has been suggested that the utilization of joint arthroplasty in patients with rheumatoid arthritis (RA) is decreasing; however, this observation is largely based upon evidence pertaining to lower-extremity joint arthroplasty. It remains unknown if these observed trends also hold true for shoulder arthroplasty. The purpose of this study is to utilize a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. Secondarily, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and to compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. Using a large population database in the US, we determined the annual rates of shoulder arthroplasty (overall and individual) in RA patients between 2002 and 2011. Early adverse events, length of stay, and hospitalization costs were determined and compared with those of non-RA patients undergoing shoulder arthroplasty. Overall, we identified 332,593 patients who underwent shoulder arthroplasty between 2002 and 2011, of whom 17,883 patients (5.4%) had a diagnosis of RA. Over the study period, there was a significant increase in the utilization of shoulder arthroplasty in RA patients, particularly total shoulder arthroplasty. Over the same period, there was a significant increase in the number of RA patients who underwent shoulder arthroplasty with a diagnosis of rotator cuff disease. There were no significant differences in adverse events or mean hospitalization costs between RA and non-RA patients. Non-RA patients had a significantly shorter length of stay; however, the difference did not appear to be clinically significant. In conclusion, the utilization of shoulder arthroplasty in patients with RA significantly increased from 2002 to 2011, which may partly reflect a trend toward management of rotator cuff disease with arthroplasty rather than repair.

Continue to: It has been suggested...

It has been suggested that the utilization of total joint arthroplasty (TJA) in patients with rheumatoid arthritis (RA) is decreasing over time;¹ however, this observation is largely based upon evidence pertaining to lower extremity TJA.² It remains unknown if these observed trends also hold true for shoulder arthroplasty, whereby the utilization of shoulder arthroplasty in RA patients is not limited to the management of end-stage inflammatory arthropathy. In this study, we used a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. As a secondary objective, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. We hypothesize that the utilization of shoulder arthroplasty in RA patients would be decreasing, but adverse events, length of stay, and hospitalization costs would not differ between patients with and without RA undergoing shoulder arthroplasty.

METHODS

We conducted a retrospective cohort study using the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) from 2002 to 2011.³ The NIS comprises a 20% stratified sample of all hospital discharges in the US. The NIS includes information about patient characteristics (age, sex, insurance status, and medical comorbidities) and hospitalization outcomes (adverse events, costs, and length of stay). The NIS allows identification of hospitalizations according to procedures and diagnoses using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Given the anonymity of this study, it was exempt from Institutional Review Board ethics approval.

Hospitalizations were selected for the study based on ICD-9-CM procedural codes for hemiarthroplasty (81.81), anatomic total shoulder arthroplasty (TSA) (81.80), and reverse TSA (81.88). These patients were then stratified by an ICD-9-CM diagnosis of RA (714.X). We also utilized ICD-9-CM diagnosis codes to determine the presence of rotator cuff pathology at the time of shoulder arthroplasty (726.13, 727.61, 840.4) and to exclude patients with a history of trauma (812.X, 716.11, 733.8X). In a separate analysis, all patients in the NIS database with an ICD-9-CM diagnosis of RA were identified for each calendar year of the study, and a national estimate of RA patients was generated annually to assess overall and individual utilization rates of shoulder arthroplasty in this population (the national estimate served as the denominator).

Preoperative patient data withdrawn from the NIS included age, sex, insurance status, and medical comorbidities. An Elixhauser Comorbidity Index (ECI) was generated for each patient based on the presence of 29 comorbid conditions. The ECI was chosen because of its capacity to accurately predict mortality and represent the patient burden of comorbidities in similar administrative database studies.^4-6

Early adverse events were also chosen based on ICD-9-CM diagnosis codes (Appendix A), and included the following: death, acute kidney injury, cardiac arrest, thromboembolic event, myocardial infarction, peripheral nerve injury, pneumonia, sepsis, stroke, surgical site infection, urinary tract infection, and wound dehiscence. The overall adverse event rate was defined as the occurrence of ≥1 of the above adverse events in a patient.

Appendix A. ICD-9-CM Codes Corresponding to Postoperative Adverse Events

Abbreviation: ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification

Length of stay and total hospital charges were available for each patient. Length of stay represents the number of calendar days a patient stayed in the hospital. All hospital charges were converted to hospitalization costs using the HCUP Cost-to-Charge Ratio Files. All hospitalization costs were adjusted for inflation using the US Bureau of Labor statistics yearly inflation calculator to represent charges in the year 2011, which was the final and most recent year in this study.

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were conducted using Stata version 13.1 (StataCorp, LP). All analyses took into account the complex survey design of the NIS. Discharge weights, strata, and cluster variables were included to correctly estimate variance and to produce national estimates from the stratified sample. Pearson’s chi-squared test was used to compare age, sex, ECI, and insurance status between RA and non-RA patients undergoing shoulder arthroplasty.

Bivariate and multivariate logistic regressions were subsequently used to compare the rates of adverse events between RA and non-RA patients undergoing shoulder arthroplasty (non-RA cases were used as the reference). Multivariate linear regressions were used to compare hospital length of stay and hospitalization costs between RA and non-RA patients undergoing shoulder arthroplasty. The multivariate regressions were adjusted for baseline differences in age, sex, ECI, and insurance status. Cochran-Armitage tests for trend were used to assess trends over time. All tests were 2-tailed, and the statistical difference was established at a 2-sided α level of 0.05 (P < .05).

RESULTS

Overall, we identified 332,593 patients who underwent shoulder arthroplasty in the US between 2002 and 2011, of which 17,883 patients (5.4%) had a diagnosis of RA. In comparison with non-RA patients undergoing shoulder arthroplasty, patients with RA at the time of shoulder arthroplasty were significantly younger (65.2 ± 12.5 years vs 68.4 ± 11.0 years, P < .001), included a significantly greater proportion of female patients (76.7% vs 53.8%, P < .001), and included a significantly higher proportion of patients with Medicaid insurance (3.6% vs 2.3%, P < .001). There were no significant differences in the mean ECI between patients with and without a diagnosis of RA (Table 1). As depicted in Table 1, there were significant differences in the utilization of specific shoulder arthroplasty types between patients with and without RA, whereby a significantly greater proportion of RA patients underwent hemiarthroplasty (HA) (31.6% vs 29.3%, P = .002) and reverse TSA (7.7% vs 6.6%, P = .002), whereas a significantly greater proportion of non-RA patients underwent anatomic SA (64.0% vs 60.8%, P = .002).

Over the study period from 2002 to 2011, there was a significant increase in the overall utilization of shoulder arthroplasty in RA patients, as indicated by both the absolute number and the proportion of patients with a diagnosis of RA (P < .001) (Table 2, Figure). More specifically, 0.39% of RA patients underwent shoulder arthroplasty in 2002, as compared with 0.58% of RA patients in 2011 (P < .001) (Table 2). With respect to specific arthroplasty types, there was an exponential rise in the utilization of reverse TSA beginning in 2010 and a corresponding decrease in the rates of both HA and anatomic TSA (Table 2, Figure). In addition to changes in shoulder arthroplasty utilization over time among RA patients, we also observed a significant increase in the number of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease (9.7% in 2002 to 15.2% in 2011, P < .001).

Table 2. The Annual Utilization of Shoulder Arthroplasty Among Patients with a Diagnosis of Rheumatoid Arthritis.

^aRate determined as number of RA patients undergoing shoulder arthroplasty compared to the number of patients with an RA diagnosis in the stated calendar year.

Abbreviations: HA, hemiarthroplasty; RA, rheumatoid arthritis; TSA, total shoulder arthroplasty.

Continue to: Among patients with RA...

Among patients with RA undergoing shoulder arthroplasty, the overall rate of early adverse events was 3.12%, of which the most common early adverse events were urinary tract infections (1.8%), acute kidney injury (0.66%), and pneumonia (0.38%) (Table 3). As compared with patients without a diagnosis of RA undergoing shoulder arthroplasty, there were no significant differences in the overall and individual rates of early adverse events (Table 3).

Table 3. A Comparison of Early Adverse Events, Length of Stay, and Cost Between Patients With and Without Rheumatoid Arthritis (RA) Undergoing Shoulder Arthroplasty

^aReported in days. ^bReported in 2011 US dollars, adjusted for inflation.

The mean length of stay following shoulder arthroplasty in RA patients was 2.4 ± 1.6 days, and the mean hospitalization cost was $14,787 ± $7625 (Table 3). As compared with non-RA patients undergoing shoulder arthroplasty, there were no significant differences in the mean hospitalization costs; however, non-RA patients had a significantly shorter length of stay by 0.1 days (P = .002) (Table 3).

DISCUSSION

In this study, we observed that the utilization of shoulder arthroplasty in patients with RA increased significantly in the decade from 2002 to 2011, largely related to a rise in TSA. Interestingly, we also observed a corresponding rise in the proportion of RA patients undergoing shoulder arthroplasty with a diagnosis of rotator cuff disease, and we believe that this may partly account for the recent increase in the use of the reverse TSA in this patient population. Additionally, we found shoulder arthroplasty in RA patients to be safe in the early postoperative period, with no significant increase in cost as compared with patients undergoing shoulder arthroplasty without a diagnosis of RA. Although we did observe a significant increase in length of stay among RA patients as compared with non-RA patients, the absolute difference was only 0.1 days, and given the aforementioned similarities in cost between RA and non-RA patients, we do not believe this difference to be clinically significant.

It has been theorized that the utilization of TJA in RA patients has been decreasing with improvements in medical management; however, this is largely based upon literature pertaining to lower extremity TJA.² On the contrary, past research pertaining to the utilization of shoulder arthroplasty in RA patients has been highly variable. For instance, a Swedish study demonstrated a statistically significant decrease in admissions associated with RA-related upper limb surgery and a stable rate of shoulder arthroplasty between 1998 and 2004.⁷ Similarly, a Finnish study demonstrated that the annual incidence of primary joint arthroplasty in RA patients had declined from 1995 to 2010, with a greater decline for upper-limb arthroplasty as compared with lower-limb arthroplasty.⁸ Despite these European observations, Jain and colleagues⁹ reported an increasing rate of TSA among RA patients in the US between the years 1992 and 2005. In this study, we demonstrate a clear increase in the utilization of shoulder arthroplasty among RA patients between 2002 and 2011. What was most striking about our observation was that the rise in utilization appeared to be driven by an increase in TSA, whereas the utilization of HA decreased over time. This change in practice likely reflects several factors, including the multitude of studies that have demonstrated improved outcomes with anatomic TSA as compared with HA in RA patients.^10-14

Perhaps the most interesting aspect of our data was the recent exponential rise in the utilization of the reverse TSA. Despite improved outcomes following TSA as compared with HA in RA patients, these outcomes all appear to be highly dependent upon the integrity of the rotator cuff.¹⁰ In fact, there is evidence that failure of the rotator cuff could be as high as 75% within 10 years of TSA in patients with RA,¹⁵ which ultimately could jeopardize the long-term durability of the TSA implant in this patient population.¹¹ For this reason, interest in the reverse TSA for the RA patient population has increased since its introduction in the US in 2004;¹⁶ in fact, in RA patients with end-stage inflammatory arthropathy and a damaged rotator cuff, the reverse TSA has demonstrated excellent results.^17-20 Based upon this evidence, it is not surprising that we found an exponential rise in the use of the reverse TSA since 2010, which corresponds to the introduction of an ICD-9 code for this implant.²¹ Prior to 2010, it is likely that many implanted reverse TSAs were coded as TSA, and for this reason, we believe that the observed rise in the utilization of TSA in RA patients prior to 2010 may have been partly fueled by an increase in the use of the reverse TSA. To further support this theory, there was a dramatic decrease in the use of anatomic TSA following 2010, and we believe this was related to increased awareness of the newly introduced reverse TSA code among surgeons.

Another consideration when examining the utilization of shoulder arthroplasty in RA patients is its versatility in managing different disease states, including rotator cuff disease. As has been documented in the literature, outcomes of rotator cuff repair in RA patients are discouraging.²² For this reason, it is reasonable for surgeons and patients with RA to consider alternatives to rotator cuff repair when nonoperative management has failed to provide adequate improvement in symptoms. One alternative may be shoulder arthroplasty, namely the reverse TSA. In this study, we observed a significant increase in the rate of diagnosis of rotator cuff disease among RA patients undergoing shoulder arthroplasty from 2002 to 2011 (9.7% in 2002 to 15.2% in 2011, P < .001), and it is our belief that the simultaneous increase in the diagnosis of rotator cuff disease and use of TSA is not coincidental. More specifically, there is likely an emerging trend among surgeons toward using the reverse TSA to manage rotator cuff tears in the RA population, rather than undertaking a rotator cuff repair that carries a high rate of failure. Going forward, there is a need to not only identify this trend more clearly but to also compare the outcomes between reverse TSA and rotator cuff repair in the management of rotator cuff tears in RA patients.

Continue to: In this study, we observed...

In this study, we observed that RA patients undergoing shoulder arthroplasty were significantly younger than non-RA patients undergoing shoulder arthroplasty. At first, this observation seems to counter recent literature suggesting that the age of patients with inflammatory arthropathy undergoing TJA is increasing over time;¹ however, looking more closely at the data, it becomes clearer that the mean age we report is actually a relative increase as compared with past clinical studies pertaining to RA patients undergoing shoulder arthroplasty (mean ages of 47 years,²³ 55 years,²⁴ 60 years,¹⁰ and 62 years²⁵). On the other hand, the continued existence of an age gap between RA and non-RA patients undergoing shoulder arthroplasty may be the result of several possible phenomena. First, this may reflect issues with patient access to and coverage of expensive biologic antirheumatic medication that would otherwise mitigate disease progression. For instance, the out-of-pocket expense for biologic medication through Medicaid and Medicare is substantial,²⁶ which has direct implications on over two-thirds of our RA cohort. Second, it may be skewed by the proportion of RA patients who have previously been or continue to be poorly managed, enabling disease progression to end-stage arthropathy at a younger age. Ultimately, further investigation is needed to determine the reasons for this continued age disparity.

In comparing RA and non-RA patients undergoing shoulder arthroplasty, we did not find a significant difference in the overall nor the individual rates of early adverse events. This finding appears to be unique, as similar studies pertaining to total knee arthroplasty (TKA) demonstrated a significantly higher incidence of postoperative pneumonia and bleeding requiring transfusion among RA patients as compared with non-RA patients.²⁷ In patients with RA being treated with biologic medication and undergoing shoulder arthroplasty, the frequent concern in the postoperative period is the integrity of the wound and the potential for infection.²⁸ In this study, we did not find a significant difference in the rate of early infection, and although the difference in the rate of early wound dehiscence approached significance, it did not meet the threshold of 0.05 (P = .09). This finding is in keeping with the aforementioned NIS study pertaining to TKA, and we believe that it likely reflects the short duration of follow-up for patients in both studies. Given the nature of the database we utilized, we were only privy to complications that arose during the inpatient hospital stay, and it is likely that the clear majority of patients who develop a postoperative infection or wound dehiscence do so in the postoperative setting following discharge. A second concern regarding postoperative wound complications is the management of biologic medication in the perioperative period, which we cannot determine using this database. Despite all these limitations specific to this database, a past systematic review of reverse TSA in RA patients found a low rate of deep infection after reverse TSA in RA patients (3.3%),¹⁷ which was not higher than that after shoulder arthroplasty performed in non-RA patients.

A final demonstration from this study is that the hospital length of stay was significantly longer for RA patients than non-RA patients undergoing shoulder arthroplasty; however, given that the difference was only 0.1 days, and there was no significant difference in hospitalization cost, we are inclined to believe that statistical significance may not translate into clinical significance in this scenario. Ultimately, we do believe that length of stay is an important consideration in the current healthcare system, and given our finding that shoulder arthroplasty in the RA patient is safe in the early postoperative period, that a prolonged postoperative hospitalization is not warranted on the sole basis of a patient’s history of RA.

As with all studies using data from a search of an administrative database, such as the NIS database, this study has limitations. First, this type of research is limited by the reliability of both diagnosis and procedural coding. Although the NIS database has demonstrated high reliability,³ it is still possible that events may have been miscoded. Second, the tracking period for adverse events is limited to the inpatient hospital stay, which may be too short to detect certain postoperative complications. As such, the rates we report are likely underestimates of the true incidence of these complications, but this is true for both the RA and non-RA populations. Third, the comparisons we draw between RA and non-RA patients are limited to the scope of the NIS database and the available data; as such, we could not draw comparisons between preoperative disease stage, intraoperative findings, and postoperative course following hospital discharge. Lastly, our data are limited to a distinct period between 2002 and 2011 and may not reflect current practice. Ultimately, our findings may underestimate current trends in shoulder arthroplasty utilization among RA patients, particularly for the reverse TSA.

CONCLUSION

In this study, we found that the utilization of shoulder arthroplasty in patients with RA increased significantly from 2002 to 2011, largely related to a rise in the utilization of TSA. Similarly, we observed a rise in the proportion of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease, and we believe the increased utilization of shoulder arthroplasty among RA patients resulted from management of both end-stage inflammatory arthropathy and rotator cuff disease. Although we did not find a significant difference between RA and non-RA patients in the rates of early adverse events and overall hospitalization costs following shoulder arthroplasty, length of stay was significantly longer among RA patients; however, the absolute difference does not appear to be clinically significant.

ABSTRACT

It has been suggested that the utilization of joint arthroplasty in patients with rheumatoid arthritis (RA) is decreasing; however, this observation is largely based upon evidence pertaining to lower-extremity joint arthroplasty. It remains unknown if these observed trends also hold true for shoulder arthroplasty. The purpose of this study is to utilize a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. Secondarily, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and to compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. Using a large population database in the US, we determined the annual rates of shoulder arthroplasty (overall and individual) in RA patients between 2002 and 2011. Early adverse events, length of stay, and hospitalization costs were determined and compared with those of non-RA patients undergoing shoulder arthroplasty. Overall, we identified 332,593 patients who underwent shoulder arthroplasty between 2002 and 2011, of whom 17,883 patients (5.4%) had a diagnosis of RA. Over the study period, there was a significant increase in the utilization of shoulder arthroplasty in RA patients, particularly total shoulder arthroplasty. Over the same period, there was a significant increase in the number of RA patients who underwent shoulder arthroplasty with a diagnosis of rotator cuff disease. There were no significant differences in adverse events or mean hospitalization costs between RA and non-RA patients. Non-RA patients had a significantly shorter length of stay; however, the difference did not appear to be clinically significant. In conclusion, the utilization of shoulder arthroplasty in patients with RA significantly increased from 2002 to 2011, which may partly reflect a trend toward management of rotator cuff disease with arthroplasty rather than repair.

Continue to: It has been suggested...

It has been suggested that the utilization of total joint arthroplasty (TJA) in patients with rheumatoid arthritis (RA) is decreasing over time;¹ however, this observation is largely based upon evidence pertaining to lower extremity TJA.² It remains unknown if these observed trends also hold true for shoulder arthroplasty, whereby the utilization of shoulder arthroplasty in RA patients is not limited to the management of end-stage inflammatory arthropathy. In this study, we used a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. As a secondary objective, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. We hypothesize that the utilization of shoulder arthroplasty in RA patients would be decreasing, but adverse events, length of stay, and hospitalization costs would not differ between patients with and without RA undergoing shoulder arthroplasty.

METHODS

We conducted a retrospective cohort study using the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) from 2002 to 2011.³ The NIS comprises a 20% stratified sample of all hospital discharges in the US. The NIS includes information about patient characteristics (age, sex, insurance status, and medical comorbidities) and hospitalization outcomes (adverse events, costs, and length of stay). The NIS allows identification of hospitalizations according to procedures and diagnoses using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Given the anonymity of this study, it was exempt from Institutional Review Board ethics approval.

Hospitalizations were selected for the study based on ICD-9-CM procedural codes for hemiarthroplasty (81.81), anatomic total shoulder arthroplasty (TSA) (81.80), and reverse TSA (81.88). These patients were then stratified by an ICD-9-CM diagnosis of RA (714.X). We also utilized ICD-9-CM diagnosis codes to determine the presence of rotator cuff pathology at the time of shoulder arthroplasty (726.13, 727.61, 840.4) and to exclude patients with a history of trauma (812.X, 716.11, 733.8X). In a separate analysis, all patients in the NIS database with an ICD-9-CM diagnosis of RA were identified for each calendar year of the study, and a national estimate of RA patients was generated annually to assess overall and individual utilization rates of shoulder arthroplasty in this population (the national estimate served as the denominator).

Preoperative patient data withdrawn from the NIS included age, sex, insurance status, and medical comorbidities. An Elixhauser Comorbidity Index (ECI) was generated for each patient based on the presence of 29 comorbid conditions. The ECI was chosen because of its capacity to accurately predict mortality and represent the patient burden of comorbidities in similar administrative database studies.^4-6

Early adverse events were also chosen based on ICD-9-CM diagnosis codes (Appendix A), and included the following: death, acute kidney injury, cardiac arrest, thromboembolic event, myocardial infarction, peripheral nerve injury, pneumonia, sepsis, stroke, surgical site infection, urinary tract infection, and wound dehiscence. The overall adverse event rate was defined as the occurrence of ≥1 of the above adverse events in a patient.

Appendix A. ICD-9-CM Codes Corresponding to Postoperative Adverse Events

Abbreviation: ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification

Length of stay and total hospital charges were available for each patient. Length of stay represents the number of calendar days a patient stayed in the hospital. All hospital charges were converted to hospitalization costs using the HCUP Cost-to-Charge Ratio Files. All hospitalization costs were adjusted for inflation using the US Bureau of Labor statistics yearly inflation calculator to represent charges in the year 2011, which was the final and most recent year in this study.

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were conducted using Stata version 13.1 (StataCorp, LP). All analyses took into account the complex survey design of the NIS. Discharge weights, strata, and cluster variables were included to correctly estimate variance and to produce national estimates from the stratified sample. Pearson’s chi-squared test was used to compare age, sex, ECI, and insurance status between RA and non-RA patients undergoing shoulder arthroplasty.

Bivariate and multivariate logistic regressions were subsequently used to compare the rates of adverse events between RA and non-RA patients undergoing shoulder arthroplasty (non-RA cases were used as the reference). Multivariate linear regressions were used to compare hospital length of stay and hospitalization costs between RA and non-RA patients undergoing shoulder arthroplasty. The multivariate regressions were adjusted for baseline differences in age, sex, ECI, and insurance status. Cochran-Armitage tests for trend were used to assess trends over time. All tests were 2-tailed, and the statistical difference was established at a 2-sided α level of 0.05 (P < .05).

RESULTS

Overall, we identified 332,593 patients who underwent shoulder arthroplasty in the US between 2002 and 2011, of which 17,883 patients (5.4%) had a diagnosis of RA. In comparison with non-RA patients undergoing shoulder arthroplasty, patients with RA at the time of shoulder arthroplasty were significantly younger (65.2 ± 12.5 years vs 68.4 ± 11.0 years, P < .001), included a significantly greater proportion of female patients (76.7% vs 53.8%, P < .001), and included a significantly higher proportion of patients with Medicaid insurance (3.6% vs 2.3%, P < .001). There were no significant differences in the mean ECI between patients with and without a diagnosis of RA (Table 1). As depicted in Table 1, there were significant differences in the utilization of specific shoulder arthroplasty types between patients with and without RA, whereby a significantly greater proportion of RA patients underwent hemiarthroplasty (HA) (31.6% vs 29.3%, P = .002) and reverse TSA (7.7% vs 6.6%, P = .002), whereas a significantly greater proportion of non-RA patients underwent anatomic SA (64.0% vs 60.8%, P = .002).

Over the study period from 2002 to 2011, there was a significant increase in the overall utilization of shoulder arthroplasty in RA patients, as indicated by both the absolute number and the proportion of patients with a diagnosis of RA (P < .001) (Table 2, Figure). More specifically, 0.39% of RA patients underwent shoulder arthroplasty in 2002, as compared with 0.58% of RA patients in 2011 (P < .001) (Table 2). With respect to specific arthroplasty types, there was an exponential rise in the utilization of reverse TSA beginning in 2010 and a corresponding decrease in the rates of both HA and anatomic TSA (Table 2, Figure). In addition to changes in shoulder arthroplasty utilization over time among RA patients, we also observed a significant increase in the number of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease (9.7% in 2002 to 15.2% in 2011, P < .001).

Table 2. The Annual Utilization of Shoulder Arthroplasty Among Patients with a Diagnosis of Rheumatoid Arthritis.

^aRate determined as number of RA patients undergoing shoulder arthroplasty compared to the number of patients with an RA diagnosis in the stated calendar year.

Abbreviations: HA, hemiarthroplasty; RA, rheumatoid arthritis; TSA, total shoulder arthroplasty.

Continue to: Among patients with RA...

Among patients with RA undergoing shoulder arthroplasty, the overall rate of early adverse events was 3.12%, of which the most common early adverse events were urinary tract infections (1.8%), acute kidney injury (0.66%), and pneumonia (0.38%) (Table 3). As compared with patients without a diagnosis of RA undergoing shoulder arthroplasty, there were no significant differences in the overall and individual rates of early adverse events (Table 3).

Table 3. A Comparison of Early Adverse Events, Length of Stay, and Cost Between Patients With and Without Rheumatoid Arthritis (RA) Undergoing Shoulder Arthroplasty

^aReported in days. ^bReported in 2011 US dollars, adjusted for inflation.

The mean length of stay following shoulder arthroplasty in RA patients was 2.4 ± 1.6 days, and the mean hospitalization cost was $14,787 ± $7625 (Table 3). As compared with non-RA patients undergoing shoulder arthroplasty, there were no significant differences in the mean hospitalization costs; however, non-RA patients had a significantly shorter length of stay by 0.1 days (P = .002) (Table 3).

DISCUSSION

In this study, we observed that the utilization of shoulder arthroplasty in patients with RA increased significantly in the decade from 2002 to 2011, largely related to a rise in TSA. Interestingly, we also observed a corresponding rise in the proportion of RA patients undergoing shoulder arthroplasty with a diagnosis of rotator cuff disease, and we believe that this may partly account for the recent increase in the use of the reverse TSA in this patient population. Additionally, we found shoulder arthroplasty in RA patients to be safe in the early postoperative period, with no significant increase in cost as compared with patients undergoing shoulder arthroplasty without a diagnosis of RA. Although we did observe a significant increase in length of stay among RA patients as compared with non-RA patients, the absolute difference was only 0.1 days, and given the aforementioned similarities in cost between RA and non-RA patients, we do not believe this difference to be clinically significant.

It has been theorized that the utilization of TJA in RA patients has been decreasing with improvements in medical management; however, this is largely based upon literature pertaining to lower extremity TJA.² On the contrary, past research pertaining to the utilization of shoulder arthroplasty in RA patients has been highly variable. For instance, a Swedish study demonstrated a statistically significant decrease in admissions associated with RA-related upper limb surgery and a stable rate of shoulder arthroplasty between 1998 and 2004.⁷ Similarly, a Finnish study demonstrated that the annual incidence of primary joint arthroplasty in RA patients had declined from 1995 to 2010, with a greater decline for upper-limb arthroplasty as compared with lower-limb arthroplasty.⁸ Despite these European observations, Jain and colleagues⁹ reported an increasing rate of TSA among RA patients in the US between the years 1992 and 2005. In this study, we demonstrate a clear increase in the utilization of shoulder arthroplasty among RA patients between 2002 and 2011. What was most striking about our observation was that the rise in utilization appeared to be driven by an increase in TSA, whereas the utilization of HA decreased over time. This change in practice likely reflects several factors, including the multitude of studies that have demonstrated improved outcomes with anatomic TSA as compared with HA in RA patients.^10-14

Perhaps the most interesting aspect of our data was the recent exponential rise in the utilization of the reverse TSA. Despite improved outcomes following TSA as compared with HA in RA patients, these outcomes all appear to be highly dependent upon the integrity of the rotator cuff.¹⁰ In fact, there is evidence that failure of the rotator cuff could be as high as 75% within 10 years of TSA in patients with RA,¹⁵ which ultimately could jeopardize the long-term durability of the TSA implant in this patient population.¹¹ For this reason, interest in the reverse TSA for the RA patient population has increased since its introduction in the US in 2004;¹⁶ in fact, in RA patients with end-stage inflammatory arthropathy and a damaged rotator cuff, the reverse TSA has demonstrated excellent results.^17-20 Based upon this evidence, it is not surprising that we found an exponential rise in the use of the reverse TSA since 2010, which corresponds to the introduction of an ICD-9 code for this implant.²¹ Prior to 2010, it is likely that many implanted reverse TSAs were coded as TSA, and for this reason, we believe that the observed rise in the utilization of TSA in RA patients prior to 2010 may have been partly fueled by an increase in the use of the reverse TSA. To further support this theory, there was a dramatic decrease in the use of anatomic TSA following 2010, and we believe this was related to increased awareness of the newly introduced reverse TSA code among surgeons.

Another consideration when examining the utilization of shoulder arthroplasty in RA patients is its versatility in managing different disease states, including rotator cuff disease. As has been documented in the literature, outcomes of rotator cuff repair in RA patients are discouraging.²² For this reason, it is reasonable for surgeons and patients with RA to consider alternatives to rotator cuff repair when nonoperative management has failed to provide adequate improvement in symptoms. One alternative may be shoulder arthroplasty, namely the reverse TSA. In this study, we observed a significant increase in the rate of diagnosis of rotator cuff disease among RA patients undergoing shoulder arthroplasty from 2002 to 2011 (9.7% in 2002 to 15.2% in 2011, P < .001), and it is our belief that the simultaneous increase in the diagnosis of rotator cuff disease and use of TSA is not coincidental. More specifically, there is likely an emerging trend among surgeons toward using the reverse TSA to manage rotator cuff tears in the RA population, rather than undertaking a rotator cuff repair that carries a high rate of failure. Going forward, there is a need to not only identify this trend more clearly but to also compare the outcomes between reverse TSA and rotator cuff repair in the management of rotator cuff tears in RA patients.

Continue to: In this study, we observed...

In this study, we observed that RA patients undergoing shoulder arthroplasty were significantly younger than non-RA patients undergoing shoulder arthroplasty. At first, this observation seems to counter recent literature suggesting that the age of patients with inflammatory arthropathy undergoing TJA is increasing over time;¹ however, looking more closely at the data, it becomes clearer that the mean age we report is actually a relative increase as compared with past clinical studies pertaining to RA patients undergoing shoulder arthroplasty (mean ages of 47 years,²³ 55 years,²⁴ 60 years,¹⁰ and 62 years²⁵). On the other hand, the continued existence of an age gap between RA and non-RA patients undergoing shoulder arthroplasty may be the result of several possible phenomena. First, this may reflect issues with patient access to and coverage of expensive biologic antirheumatic medication that would otherwise mitigate disease progression. For instance, the out-of-pocket expense for biologic medication through Medicaid and Medicare is substantial,²⁶ which has direct implications on over two-thirds of our RA cohort. Second, it may be skewed by the proportion of RA patients who have previously been or continue to be poorly managed, enabling disease progression to end-stage arthropathy at a younger age. Ultimately, further investigation is needed to determine the reasons for this continued age disparity.

In comparing RA and non-RA patients undergoing shoulder arthroplasty, we did not find a significant difference in the overall nor the individual rates of early adverse events. This finding appears to be unique, as similar studies pertaining to total knee arthroplasty (TKA) demonstrated a significantly higher incidence of postoperative pneumonia and bleeding requiring transfusion among RA patients as compared with non-RA patients.²⁷ In patients with RA being treated with biologic medication and undergoing shoulder arthroplasty, the frequent concern in the postoperative period is the integrity of the wound and the potential for infection.²⁸ In this study, we did not find a significant difference in the rate of early infection, and although the difference in the rate of early wound dehiscence approached significance, it did not meet the threshold of 0.05 (P = .09). This finding is in keeping with the aforementioned NIS study pertaining to TKA, and we believe that it likely reflects the short duration of follow-up for patients in both studies. Given the nature of the database we utilized, we were only privy to complications that arose during the inpatient hospital stay, and it is likely that the clear majority of patients who develop a postoperative infection or wound dehiscence do so in the postoperative setting following discharge. A second concern regarding postoperative wound complications is the management of biologic medication in the perioperative period, which we cannot determine using this database. Despite all these limitations specific to this database, a past systematic review of reverse TSA in RA patients found a low rate of deep infection after reverse TSA in RA patients (3.3%),¹⁷ which was not higher than that after shoulder arthroplasty performed in non-RA patients.

A final demonstration from this study is that the hospital length of stay was significantly longer for RA patients than non-RA patients undergoing shoulder arthroplasty; however, given that the difference was only 0.1 days, and there was no significant difference in hospitalization cost, we are inclined to believe that statistical significance may not translate into clinical significance in this scenario. Ultimately, we do believe that length of stay is an important consideration in the current healthcare system, and given our finding that shoulder arthroplasty in the RA patient is safe in the early postoperative period, that a prolonged postoperative hospitalization is not warranted on the sole basis of a patient’s history of RA.

As with all studies using data from a search of an administrative database, such as the NIS database, this study has limitations. First, this type of research is limited by the reliability of both diagnosis and procedural coding. Although the NIS database has demonstrated high reliability,³ it is still possible that events may have been miscoded. Second, the tracking period for adverse events is limited to the inpatient hospital stay, which may be too short to detect certain postoperative complications. As such, the rates we report are likely underestimates of the true incidence of these complications, but this is true for both the RA and non-RA populations. Third, the comparisons we draw between RA and non-RA patients are limited to the scope of the NIS database and the available data; as such, we could not draw comparisons between preoperative disease stage, intraoperative findings, and postoperative course following hospital discharge. Lastly, our data are limited to a distinct period between 2002 and 2011 and may not reflect current practice. Ultimately, our findings may underestimate current trends in shoulder arthroplasty utilization among RA patients, particularly for the reverse TSA.

CONCLUSION

In this study, we found that the utilization of shoulder arthroplasty in patients with RA increased significantly from 2002 to 2011, largely related to a rise in the utilization of TSA. Similarly, we observed a rise in the proportion of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease, and we believe the increased utilization of shoulder arthroplasty among RA patients resulted from management of both end-stage inflammatory arthropathy and rotator cuff disease. Although we did not find a significant difference between RA and non-RA patients in the rates of early adverse events and overall hospitalization costs following shoulder arthroplasty, length of stay was significantly longer among RA patients; however, the absolute difference does not appear to be clinically significant.

ABSTRACT

It has been suggested that the utilization of joint arthroplasty in patients with rheumatoid arthritis (RA) is decreasing; however, this observation is largely based upon evidence pertaining to lower-extremity joint arthroplasty. It remains unknown if these observed trends also hold true for shoulder arthroplasty. The purpose of this study is to utilize a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. Secondarily, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and to compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. Using a large population database in the US, we determined the annual rates of shoulder arthroplasty (overall and individual) in RA patients between 2002 and 2011. Early adverse events, length of stay, and hospitalization costs were determined and compared with those of non-RA patients undergoing shoulder arthroplasty. Overall, we identified 332,593 patients who underwent shoulder arthroplasty between 2002 and 2011, of whom 17,883 patients (5.4%) had a diagnosis of RA. Over the study period, there was a significant increase in the utilization of shoulder arthroplasty in RA patients, particularly total shoulder arthroplasty. Over the same period, there was a significant increase in the number of RA patients who underwent shoulder arthroplasty with a diagnosis of rotator cuff disease. There were no significant differences in adverse events or mean hospitalization costs between RA and non-RA patients. Non-RA patients had a significantly shorter length of stay; however, the difference did not appear to be clinically significant. In conclusion, the utilization of shoulder arthroplasty in patients with RA significantly increased from 2002 to 2011, which may partly reflect a trend toward management of rotator cuff disease with arthroplasty rather than repair.

Continue to: It has been suggested...

It has been suggested that the utilization of total joint arthroplasty (TJA) in patients with rheumatoid arthritis (RA) is decreasing over time;¹ however, this observation is largely based upon evidence pertaining to lower extremity TJA.² It remains unknown if these observed trends also hold true for shoulder arthroplasty, whereby the utilization of shoulder arthroplasty in RA patients is not limited to the management of end-stage inflammatory arthropathy. In this study, we used a nationally representative population database in the US to identify trends in the utilization of shoulder arthroplasty among patients with RA. As a secondary objective, we sought to determine the rate of early adverse events, length of stay, and hospitalization costs associated with RA patients undergoing shoulder arthroplasty and compare these outcomes to those of patients without a diagnosis of RA undergoing shoulder arthroplasty. We hypothesize that the utilization of shoulder arthroplasty in RA patients would be decreasing, but adverse events, length of stay, and hospitalization costs would not differ between patients with and without RA undergoing shoulder arthroplasty.

METHODS

We conducted a retrospective cohort study using the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) from 2002 to 2011.³ The NIS comprises a 20% stratified sample of all hospital discharges in the US. The NIS includes information about patient characteristics (age, sex, insurance status, and medical comorbidities) and hospitalization outcomes (adverse events, costs, and length of stay). The NIS allows identification of hospitalizations according to procedures and diagnoses using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Given the anonymity of this study, it was exempt from Institutional Review Board ethics approval.

Hospitalizations were selected for the study based on ICD-9-CM procedural codes for hemiarthroplasty (81.81), anatomic total shoulder arthroplasty (TSA) (81.80), and reverse TSA (81.88). These patients were then stratified by an ICD-9-CM diagnosis of RA (714.X). We also utilized ICD-9-CM diagnosis codes to determine the presence of rotator cuff pathology at the time of shoulder arthroplasty (726.13, 727.61, 840.4) and to exclude patients with a history of trauma (812.X, 716.11, 733.8X). In a separate analysis, all patients in the NIS database with an ICD-9-CM diagnosis of RA were identified for each calendar year of the study, and a national estimate of RA patients was generated annually to assess overall and individual utilization rates of shoulder arthroplasty in this population (the national estimate served as the denominator).

Preoperative patient data withdrawn from the NIS included age, sex, insurance status, and medical comorbidities. An Elixhauser Comorbidity Index (ECI) was generated for each patient based on the presence of 29 comorbid conditions. The ECI was chosen because of its capacity to accurately predict mortality and represent the patient burden of comorbidities in similar administrative database studies.^4-6

Early adverse events were also chosen based on ICD-9-CM diagnosis codes (Appendix A), and included the following: death, acute kidney injury, cardiac arrest, thromboembolic event, myocardial infarction, peripheral nerve injury, pneumonia, sepsis, stroke, surgical site infection, urinary tract infection, and wound dehiscence. The overall adverse event rate was defined as the occurrence of ≥1 of the above adverse events in a patient.

Appendix A. ICD-9-CM Codes Corresponding to Postoperative Adverse Events

Abbreviation: ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification

Length of stay and total hospital charges were available for each patient. Length of stay represents the number of calendar days a patient stayed in the hospital. All hospital charges were converted to hospitalization costs using the HCUP Cost-to-Charge Ratio Files. All hospitalization costs were adjusted for inflation using the US Bureau of Labor statistics yearly inflation calculator to represent charges in the year 2011, which was the final and most recent year in this study.

Continue to: Statistical analysis...

STATISTICAL ANALYSIS

Statistical analyses were conducted using Stata version 13.1 (StataCorp, LP). All analyses took into account the complex survey design of the NIS. Discharge weights, strata, and cluster variables were included to correctly estimate variance and to produce national estimates from the stratified sample. Pearson’s chi-squared test was used to compare age, sex, ECI, and insurance status between RA and non-RA patients undergoing shoulder arthroplasty.

Bivariate and multivariate logistic regressions were subsequently used to compare the rates of adverse events between RA and non-RA patients undergoing shoulder arthroplasty (non-RA cases were used as the reference). Multivariate linear regressions were used to compare hospital length of stay and hospitalization costs between RA and non-RA patients undergoing shoulder arthroplasty. The multivariate regressions were adjusted for baseline differences in age, sex, ECI, and insurance status. Cochran-Armitage tests for trend were used to assess trends over time. All tests were 2-tailed, and the statistical difference was established at a 2-sided α level of 0.05 (P < .05).

RESULTS

Overall, we identified 332,593 patients who underwent shoulder arthroplasty in the US between 2002 and 2011, of which 17,883 patients (5.4%) had a diagnosis of RA. In comparison with non-RA patients undergoing shoulder arthroplasty, patients with RA at the time of shoulder arthroplasty were significantly younger (65.2 ± 12.5 years vs 68.4 ± 11.0 years, P < .001), included a significantly greater proportion of female patients (76.7% vs 53.8%, P < .001), and included a significantly higher proportion of patients with Medicaid insurance (3.6% vs 2.3%, P < .001). There were no significant differences in the mean ECI between patients with and without a diagnosis of RA (Table 1). As depicted in Table 1, there were significant differences in the utilization of specific shoulder arthroplasty types between patients with and without RA, whereby a significantly greater proportion of RA patients underwent hemiarthroplasty (HA) (31.6% vs 29.3%, P = .002) and reverse TSA (7.7% vs 6.6%, P = .002), whereas a significantly greater proportion of non-RA patients underwent anatomic SA (64.0% vs 60.8%, P = .002).

Over the study period from 2002 to 2011, there was a significant increase in the overall utilization of shoulder arthroplasty in RA patients, as indicated by both the absolute number and the proportion of patients with a diagnosis of RA (P < .001) (Table 2, Figure). More specifically, 0.39% of RA patients underwent shoulder arthroplasty in 2002, as compared with 0.58% of RA patients in 2011 (P < .001) (Table 2). With respect to specific arthroplasty types, there was an exponential rise in the utilization of reverse TSA beginning in 2010 and a corresponding decrease in the rates of both HA and anatomic TSA (Table 2, Figure). In addition to changes in shoulder arthroplasty utilization over time among RA patients, we also observed a significant increase in the number of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease (9.7% in 2002 to 15.2% in 2011, P < .001).

Table 2. The Annual Utilization of Shoulder Arthroplasty Among Patients with a Diagnosis of Rheumatoid Arthritis.

^aRate determined as number of RA patients undergoing shoulder arthroplasty compared to the number of patients with an RA diagnosis in the stated calendar year.

Abbreviations: HA, hemiarthroplasty; RA, rheumatoid arthritis; TSA, total shoulder arthroplasty.

Continue to: Among patients with RA...

Among patients with RA undergoing shoulder arthroplasty, the overall rate of early adverse events was 3.12%, of which the most common early adverse events were urinary tract infections (1.8%), acute kidney injury (0.66%), and pneumonia (0.38%) (Table 3). As compared with patients without a diagnosis of RA undergoing shoulder arthroplasty, there were no significant differences in the overall and individual rates of early adverse events (Table 3).

Table 3. A Comparison of Early Adverse Events, Length of Stay, and Cost Between Patients With and Without Rheumatoid Arthritis (RA) Undergoing Shoulder Arthroplasty

^aReported in days. ^bReported in 2011 US dollars, adjusted for inflation.

The mean length of stay following shoulder arthroplasty in RA patients was 2.4 ± 1.6 days, and the mean hospitalization cost was $14,787 ± $7625 (Table 3). As compared with non-RA patients undergoing shoulder arthroplasty, there were no significant differences in the mean hospitalization costs; however, non-RA patients had a significantly shorter length of stay by 0.1 days (P = .002) (Table 3).

DISCUSSION

In this study, we observed that the utilization of shoulder arthroplasty in patients with RA increased significantly in the decade from 2002 to 2011, largely related to a rise in TSA. Interestingly, we also observed a corresponding rise in the proportion of RA patients undergoing shoulder arthroplasty with a diagnosis of rotator cuff disease, and we believe that this may partly account for the recent increase in the use of the reverse TSA in this patient population. Additionally, we found shoulder arthroplasty in RA patients to be safe in the early postoperative period, with no significant increase in cost as compared with patients undergoing shoulder arthroplasty without a diagnosis of RA. Although we did observe a significant increase in length of stay among RA patients as compared with non-RA patients, the absolute difference was only 0.1 days, and given the aforementioned similarities in cost between RA and non-RA patients, we do not believe this difference to be clinically significant.

It has been theorized that the utilization of TJA in RA patients has been decreasing with improvements in medical management; however, this is largely based upon literature pertaining to lower extremity TJA.² On the contrary, past research pertaining to the utilization of shoulder arthroplasty in RA patients has been highly variable. For instance, a Swedish study demonstrated a statistically significant decrease in admissions associated with RA-related upper limb surgery and a stable rate of shoulder arthroplasty between 1998 and 2004.⁷ Similarly, a Finnish study demonstrated that the annual incidence of primary joint arthroplasty in RA patients had declined from 1995 to 2010, with a greater decline for upper-limb arthroplasty as compared with lower-limb arthroplasty.⁸ Despite these European observations, Jain and colleagues⁹ reported an increasing rate of TSA among RA patients in the US between the years 1992 and 2005. In this study, we demonstrate a clear increase in the utilization of shoulder arthroplasty among RA patients between 2002 and 2011. What was most striking about our observation was that the rise in utilization appeared to be driven by an increase in TSA, whereas the utilization of HA decreased over time. This change in practice likely reflects several factors, including the multitude of studies that have demonstrated improved outcomes with anatomic TSA as compared with HA in RA patients.^10-14

Perhaps the most interesting aspect of our data was the recent exponential rise in the utilization of the reverse TSA. Despite improved outcomes following TSA as compared with HA in RA patients, these outcomes all appear to be highly dependent upon the integrity of the rotator cuff.¹⁰ In fact, there is evidence that failure of the rotator cuff could be as high as 75% within 10 years of TSA in patients with RA,¹⁵ which ultimately could jeopardize the long-term durability of the TSA implant in this patient population.¹¹ For this reason, interest in the reverse TSA for the RA patient population has increased since its introduction in the US in 2004;¹⁶ in fact, in RA patients with end-stage inflammatory arthropathy and a damaged rotator cuff, the reverse TSA has demonstrated excellent results.^17-20 Based upon this evidence, it is not surprising that we found an exponential rise in the use of the reverse TSA since 2010, which corresponds to the introduction of an ICD-9 code for this implant.²¹ Prior to 2010, it is likely that many implanted reverse TSAs were coded as TSA, and for this reason, we believe that the observed rise in the utilization of TSA in RA patients prior to 2010 may have been partly fueled by an increase in the use of the reverse TSA. To further support this theory, there was a dramatic decrease in the use of anatomic TSA following 2010, and we believe this was related to increased awareness of the newly introduced reverse TSA code among surgeons.

Another consideration when examining the utilization of shoulder arthroplasty in RA patients is its versatility in managing different disease states, including rotator cuff disease. As has been documented in the literature, outcomes of rotator cuff repair in RA patients are discouraging.²² For this reason, it is reasonable for surgeons and patients with RA to consider alternatives to rotator cuff repair when nonoperative management has failed to provide adequate improvement in symptoms. One alternative may be shoulder arthroplasty, namely the reverse TSA. In this study, we observed a significant increase in the rate of diagnosis of rotator cuff disease among RA patients undergoing shoulder arthroplasty from 2002 to 2011 (9.7% in 2002 to 15.2% in 2011, P < .001), and it is our belief that the simultaneous increase in the diagnosis of rotator cuff disease and use of TSA is not coincidental. More specifically, there is likely an emerging trend among surgeons toward using the reverse TSA to manage rotator cuff tears in the RA population, rather than undertaking a rotator cuff repair that carries a high rate of failure. Going forward, there is a need to not only identify this trend more clearly but to also compare the outcomes between reverse TSA and rotator cuff repair in the management of rotator cuff tears in RA patients.

Continue to: In this study, we observed...

In this study, we observed that RA patients undergoing shoulder arthroplasty were significantly younger than non-RA patients undergoing shoulder arthroplasty. At first, this observation seems to counter recent literature suggesting that the age of patients with inflammatory arthropathy undergoing TJA is increasing over time;¹ however, looking more closely at the data, it becomes clearer that the mean age we report is actually a relative increase as compared with past clinical studies pertaining to RA patients undergoing shoulder arthroplasty (mean ages of 47 years,²³ 55 years,²⁴ 60 years,¹⁰ and 62 years²⁵). On the other hand, the continued existence of an age gap between RA and non-RA patients undergoing shoulder arthroplasty may be the result of several possible phenomena. First, this may reflect issues with patient access to and coverage of expensive biologic antirheumatic medication that would otherwise mitigate disease progression. For instance, the out-of-pocket expense for biologic medication through Medicaid and Medicare is substantial,²⁶ which has direct implications on over two-thirds of our RA cohort. Second, it may be skewed by the proportion of RA patients who have previously been or continue to be poorly managed, enabling disease progression to end-stage arthropathy at a younger age. Ultimately, further investigation is needed to determine the reasons for this continued age disparity.

In comparing RA and non-RA patients undergoing shoulder arthroplasty, we did not find a significant difference in the overall nor the individual rates of early adverse events. This finding appears to be unique, as similar studies pertaining to total knee arthroplasty (TKA) demonstrated a significantly higher incidence of postoperative pneumonia and bleeding requiring transfusion among RA patients as compared with non-RA patients.²⁷ In patients with RA being treated with biologic medication and undergoing shoulder arthroplasty, the frequent concern in the postoperative period is the integrity of the wound and the potential for infection.²⁸ In this study, we did not find a significant difference in the rate of early infection, and although the difference in the rate of early wound dehiscence approached significance, it did not meet the threshold of 0.05 (P = .09). This finding is in keeping with the aforementioned NIS study pertaining to TKA, and we believe that it likely reflects the short duration of follow-up for patients in both studies. Given the nature of the database we utilized, we were only privy to complications that arose during the inpatient hospital stay, and it is likely that the clear majority of patients who develop a postoperative infection or wound dehiscence do so in the postoperative setting following discharge. A second concern regarding postoperative wound complications is the management of biologic medication in the perioperative period, which we cannot determine using this database. Despite all these limitations specific to this database, a past systematic review of reverse TSA in RA patients found a low rate of deep infection after reverse TSA in RA patients (3.3%),¹⁷ which was not higher than that after shoulder arthroplasty performed in non-RA patients.

A final demonstration from this study is that the hospital length of stay was significantly longer for RA patients than non-RA patients undergoing shoulder arthroplasty; however, given that the difference was only 0.1 days, and there was no significant difference in hospitalization cost, we are inclined to believe that statistical significance may not translate into clinical significance in this scenario. Ultimately, we do believe that length of stay is an important consideration in the current healthcare system, and given our finding that shoulder arthroplasty in the RA patient is safe in the early postoperative period, that a prolonged postoperative hospitalization is not warranted on the sole basis of a patient’s history of RA.

As with all studies using data from a search of an administrative database, such as the NIS database, this study has limitations. First, this type of research is limited by the reliability of both diagnosis and procedural coding. Although the NIS database has demonstrated high reliability,³ it is still possible that events may have been miscoded. Second, the tracking period for adverse events is limited to the inpatient hospital stay, which may be too short to detect certain postoperative complications. As such, the rates we report are likely underestimates of the true incidence of these complications, but this is true for both the RA and non-RA populations. Third, the comparisons we draw between RA and non-RA patients are limited to the scope of the NIS database and the available data; as such, we could not draw comparisons between preoperative disease stage, intraoperative findings, and postoperative course following hospital discharge. Lastly, our data are limited to a distinct period between 2002 and 2011 and may not reflect current practice. Ultimately, our findings may underestimate current trends in shoulder arthroplasty utilization among RA patients, particularly for the reverse TSA.

CONCLUSION

In this study, we found that the utilization of shoulder arthroplasty in patients with RA increased significantly from 2002 to 2011, largely related to a rise in the utilization of TSA. Similarly, we observed a rise in the proportion of RA patients undergoing shoulder arthroplasty with a corresponding diagnosis of rotator cuff disease, and we believe the increased utilization of shoulder arthroplasty among RA patients resulted from management of both end-stage inflammatory arthropathy and rotator cuff disease. Although we did not find a significant difference between RA and non-RA patients in the rates of early adverse events and overall hospitalization costs following shoulder arthroplasty, length of stay was significantly longer among RA patients; however, the absolute difference does not appear to be clinically significant.

Take-Home Points

• The LHB tendon has been shown to be a significant pain generator in the shoulder.
• At our institution, the number of LHB tenodeses significantly increased from 2004 to 2014.
• The age of patients who underwent a LHB tenodesis did not change significantly over the study period.
• Furthermore, the percentage of shoulder procedures that involved a LHB tenodesis significantly increased over the study period.

• Biceps tenodesis has become a more common procedure to treat shoulder pathology.

Although the exact function of the long head of the biceps (LHB) tendon is not completely understood, it is accepted that the LHB tendon can be a significant source of pain within the shoulder.^1-4 Patients with symptoms related to biceps pathology often present with anterior shoulder pain that worsens with flexion and supination of the affected elbow and wrist.⁵ Although the sensitivity and specificity of physical examination maneuvers have been called into question, special tests have been developed to aid in the diagnosis of tendonitis of the LHB. These tests include the Speed, Yergason, bear hug, and uppercut tests as well as the O’Brien test (cross-body adduction).^6,7 Recent studies have found LHB pathology in 45% of patients who undergo rotator cuff repair and in 63% of patients with a subscapularis tear.^8,9

Pathology of the LHB tendon, including superior labrum anterior to posterior (SLAP) tears, can be treated in many ways.^5,10,11 Options include SLAP repair, biceps tenodesis, débridement, and biceps tenotomy.^11,12 Results of SLAP repairs have been less than optimal, but biceps tenodesis has been effective, and avoids the issue of cramping as can be seen with biceps tenotomy and débridement.^10,12,13 Surgical methods for biceps tenodesis include open subpectoral and all-arthroscopic.^11,12 Both methods have had good, reliable outcomes, but the all-arthroscopic technique is relatively new.^11,12,14We conducted a study to determine LHB tenodesis trends, including patient age at time of surgery. We used surgical data from fellowship-trained sports or shoulder/elbow orthopedic surgeons at a busy subspecialty-based shoulder orthopedic practice. We hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis.

Methods

Our Institutional Review Board exempted this study. To determine the number of LHB tenodesis procedures performed at our institution, overall and in comparison with other common arthroscopic shoulder procedures, we queried the surgical database of 4 fellowship-trained orthopedic surgeons (shoulder/elbow, Drs. Nicholson and Cole; sports, Drs. Romeo and Verma) for the period January 1, 2004 to December 31, 2014. We used Current Procedural Terminology (CPT) code 23430 to determine the number of LHB tenodesis cases, as the surgeons primarily perform an open subpectoral biceps tenodesis. Patient age at time of surgery and the date of surgery were recorded. All patients who underwent LHB tenodesis between January 1, 2004 and December 31, 2014 were included. Number of procedures performed each year by each surgeon was recorded, as were concomitant procedures performed at the same time as the LHB tenodesis. To get the denominator (and reference point) for the number of arthroscopic shoulder surgeries performed by these 4 surgeons during the study period, and thereby determine the rate of LHB tenodesis, we selected the most common shoulder arthroscopy CPT codes used in our practice: 23430, 29806, 29807, 29822, 29823, 29825, 29826, and 29827. For a patient who underwent multiple procedures on the same day (multiple CPT codes entered on the same day), only one code was counted for that day. If 23430 was among the codes, it was included, and the case was placed in the numerator; if 23430 was not among the codes, the case was placed in the denominator.

The Arthroscopy Association of North America provides descriptions for the CPT codes: 23430 (tenodesis of long tendon of biceps), 29806 (arthroscopy, shoulder, surgical; capsulorrhaphy), 29807 (arthroscopy, shoulder, surgical; repair of SLAP lesion), 29822 (arthroscopy, shoulder, surgical; débridement, limited), 29823 (arthroscopy, shoulder, surgical; débridement, extensive), 29825 (arthroscopy, shoulder, surgical; with lysis and resection of adhesions, with or without manipulation), 29826 (arthroscopy, shoulder, surgical; decompression of subacromial space with partial acromioplasty, with or without coracoacromial release), and 29827 (arthroscopy, shoulder, surgical; with rotator cuff repair).

For analysis, we divided the data into total number of arthroscopic shoulder procedures performed by each surgeon each year and number of LHB tenodesis procedures performed by each surgeon each year. Total number of patients who had an arthroscopic procedure was used to create a denominator, and number of LHB tenodesis procedures showed the percentage of arthroscopic shoulder surgery patients who underwent LHB tenodesis. (All patients who undergo biceps tenodesis also have, at the least, diagnostic shoulder arthroscopy with or without tenotomy; if the tendon is ruptured, tenotomy is unnecessary.)

Descriptive statistics were calculated as means (SDs) for continuous variables and as frequencies with percentages for categorical variables. Linear regression analysis was used to determine whether the number of LHB tenodesis procedures changed during the study period and whether patient age changed over time. Significance was set at P < .05.

Results

Of the 7640 patients who underwent arthroscopic shoulder procedures between 2004 and 2014, 2125 had LHB tenodesis (CPT code 23430).

Discussion

Tenodesis has become a common treatment option for several pathologic shoulder conditions involving the LHB tendon.⁵ We set out to determine trends in LHB tenodesis at a subspecialty-focused shoulder orthopedic practice and hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis. Our hypotheses were confirmed: The number of LHB tenodesis cases increased significantly without a significant change in patient age.

Treatment options for LHB pathology and SLAP tears include simple tenotomy, débridement, open biceps tenodesis, and arthroscopic tenodesis.^11,12,15

Am J Orthop. 2017;46(4):E219-E223. Copyright Frontline Medical Communications Inc. 2017. All rights reserved.

Take-Home Points

• The LHB tendon has been shown to be a significant pain generator in the shoulder.
• At our institution, the number of LHB tenodeses significantly increased from 2004 to 2014.
• The age of patients who underwent a LHB tenodesis did not change significantly over the study period.
• Furthermore, the percentage of shoulder procedures that involved a LHB tenodesis significantly increased over the study period.

• Biceps tenodesis has become a more common procedure to treat shoulder pathology.

Although the exact function of the long head of the biceps (LHB) tendon is not completely understood, it is accepted that the LHB tendon can be a significant source of pain within the shoulder.^1-4 Patients with symptoms related to biceps pathology often present with anterior shoulder pain that worsens with flexion and supination of the affected elbow and wrist.⁵ Although the sensitivity and specificity of physical examination maneuvers have been called into question, special tests have been developed to aid in the diagnosis of tendonitis of the LHB. These tests include the Speed, Yergason, bear hug, and uppercut tests as well as the O’Brien test (cross-body adduction).^6,7 Recent studies have found LHB pathology in 45% of patients who undergo rotator cuff repair and in 63% of patients with a subscapularis tear.^8,9

Pathology of the LHB tendon, including superior labrum anterior to posterior (SLAP) tears, can be treated in many ways.^5,10,11 Options include SLAP repair, biceps tenodesis, débridement, and biceps tenotomy.^11,12 Results of SLAP repairs have been less than optimal, but biceps tenodesis has been effective, and avoids the issue of cramping as can be seen with biceps tenotomy and débridement.^10,12,13 Surgical methods for biceps tenodesis include open subpectoral and all-arthroscopic.^11,12 Both methods have had good, reliable outcomes, but the all-arthroscopic technique is relatively new.^11,12,14We conducted a study to determine LHB tenodesis trends, including patient age at time of surgery. We used surgical data from fellowship-trained sports or shoulder/elbow orthopedic surgeons at a busy subspecialty-based shoulder orthopedic practice. We hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis.

Methods

Our Institutional Review Board exempted this study. To determine the number of LHB tenodesis procedures performed at our institution, overall and in comparison with other common arthroscopic shoulder procedures, we queried the surgical database of 4 fellowship-trained orthopedic surgeons (shoulder/elbow, Drs. Nicholson and Cole; sports, Drs. Romeo and Verma) for the period January 1, 2004 to December 31, 2014. We used Current Procedural Terminology (CPT) code 23430 to determine the number of LHB tenodesis cases, as the surgeons primarily perform an open subpectoral biceps tenodesis. Patient age at time of surgery and the date of surgery were recorded. All patients who underwent LHB tenodesis between January 1, 2004 and December 31, 2014 were included. Number of procedures performed each year by each surgeon was recorded, as were concomitant procedures performed at the same time as the LHB tenodesis. To get the denominator (and reference point) for the number of arthroscopic shoulder surgeries performed by these 4 surgeons during the study period, and thereby determine the rate of LHB tenodesis, we selected the most common shoulder arthroscopy CPT codes used in our practice: 23430, 29806, 29807, 29822, 29823, 29825, 29826, and 29827. For a patient who underwent multiple procedures on the same day (multiple CPT codes entered on the same day), only one code was counted for that day. If 23430 was among the codes, it was included, and the case was placed in the numerator; if 23430 was not among the codes, the case was placed in the denominator.

The Arthroscopy Association of North America provides descriptions for the CPT codes: 23430 (tenodesis of long tendon of biceps), 29806 (arthroscopy, shoulder, surgical; capsulorrhaphy), 29807 (arthroscopy, shoulder, surgical; repair of SLAP lesion), 29822 (arthroscopy, shoulder, surgical; débridement, limited), 29823 (arthroscopy, shoulder, surgical; débridement, extensive), 29825 (arthroscopy, shoulder, surgical; with lysis and resection of adhesions, with or without manipulation), 29826 (arthroscopy, shoulder, surgical; decompression of subacromial space with partial acromioplasty, with or without coracoacromial release), and 29827 (arthroscopy, shoulder, surgical; with rotator cuff repair).

For analysis, we divided the data into total number of arthroscopic shoulder procedures performed by each surgeon each year and number of LHB tenodesis procedures performed by each surgeon each year. Total number of patients who had an arthroscopic procedure was used to create a denominator, and number of LHB tenodesis procedures showed the percentage of arthroscopic shoulder surgery patients who underwent LHB tenodesis. (All patients who undergo biceps tenodesis also have, at the least, diagnostic shoulder arthroscopy with or without tenotomy; if the tendon is ruptured, tenotomy is unnecessary.)

Descriptive statistics were calculated as means (SDs) for continuous variables and as frequencies with percentages for categorical variables. Linear regression analysis was used to determine whether the number of LHB tenodesis procedures changed during the study period and whether patient age changed over time. Significance was set at P < .05.

Results

Of the 7640 patients who underwent arthroscopic shoulder procedures between 2004 and 2014, 2125 had LHB tenodesis (CPT code 23430).

Discussion

Tenodesis has become a common treatment option for several pathologic shoulder conditions involving the LHB tendon.⁵ We set out to determine trends in LHB tenodesis at a subspecialty-focused shoulder orthopedic practice and hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis. Our hypotheses were confirmed: The number of LHB tenodesis cases increased significantly without a significant change in patient age.

Treatment options for LHB pathology and SLAP tears include simple tenotomy, débridement, open biceps tenodesis, and arthroscopic tenodesis.^11,12,15

Am J Orthop. 2017;46(4):E219-E223. Copyright Frontline Medical Communications Inc. 2017. All rights reserved.

Take-Home Points

• The LHB tendon has been shown to be a significant pain generator in the shoulder.
• At our institution, the number of LHB tenodeses significantly increased from 2004 to 2014.
• The age of patients who underwent a LHB tenodesis did not change significantly over the study period.
• Furthermore, the percentage of shoulder procedures that involved a LHB tenodesis significantly increased over the study period.

• Biceps tenodesis has become a more common procedure to treat shoulder pathology.

Although the exact function of the long head of the biceps (LHB) tendon is not completely understood, it is accepted that the LHB tendon can be a significant source of pain within the shoulder.^1-4 Patients with symptoms related to biceps pathology often present with anterior shoulder pain that worsens with flexion and supination of the affected elbow and wrist.⁵ Although the sensitivity and specificity of physical examination maneuvers have been called into question, special tests have been developed to aid in the diagnosis of tendonitis of the LHB. These tests include the Speed, Yergason, bear hug, and uppercut tests as well as the O’Brien test (cross-body adduction).^6,7 Recent studies have found LHB pathology in 45% of patients who undergo rotator cuff repair and in 63% of patients with a subscapularis tear.^8,9

Pathology of the LHB tendon, including superior labrum anterior to posterior (SLAP) tears, can be treated in many ways.^5,10,11 Options include SLAP repair, biceps tenodesis, débridement, and biceps tenotomy.^11,12 Results of SLAP repairs have been less than optimal, but biceps tenodesis has been effective, and avoids the issue of cramping as can be seen with biceps tenotomy and débridement.^10,12,13 Surgical methods for biceps tenodesis include open subpectoral and all-arthroscopic.^11,12 Both methods have had good, reliable outcomes, but the all-arthroscopic technique is relatively new.^11,12,14We conducted a study to determine LHB tenodesis trends, including patient age at time of surgery. We used surgical data from fellowship-trained sports or shoulder/elbow orthopedic surgeons at a busy subspecialty-based shoulder orthopedic practice. We hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis.

Methods

Our Institutional Review Board exempted this study. To determine the number of LHB tenodesis procedures performed at our institution, overall and in comparison with other common arthroscopic shoulder procedures, we queried the surgical database of 4 fellowship-trained orthopedic surgeons (shoulder/elbow, Drs. Nicholson and Cole; sports, Drs. Romeo and Verma) for the period January 1, 2004 to December 31, 2014. We used Current Procedural Terminology (CPT) code 23430 to determine the number of LHB tenodesis cases, as the surgeons primarily perform an open subpectoral biceps tenodesis. Patient age at time of surgery and the date of surgery were recorded. All patients who underwent LHB tenodesis between January 1, 2004 and December 31, 2014 were included. Number of procedures performed each year by each surgeon was recorded, as were concomitant procedures performed at the same time as the LHB tenodesis. To get the denominator (and reference point) for the number of arthroscopic shoulder surgeries performed by these 4 surgeons during the study period, and thereby determine the rate of LHB tenodesis, we selected the most common shoulder arthroscopy CPT codes used in our practice: 23430, 29806, 29807, 29822, 29823, 29825, 29826, and 29827. For a patient who underwent multiple procedures on the same day (multiple CPT codes entered on the same day), only one code was counted for that day. If 23430 was among the codes, it was included, and the case was placed in the numerator; if 23430 was not among the codes, the case was placed in the denominator.

The Arthroscopy Association of North America provides descriptions for the CPT codes: 23430 (tenodesis of long tendon of biceps), 29806 (arthroscopy, shoulder, surgical; capsulorrhaphy), 29807 (arthroscopy, shoulder, surgical; repair of SLAP lesion), 29822 (arthroscopy, shoulder, surgical; débridement, limited), 29823 (arthroscopy, shoulder, surgical; débridement, extensive), 29825 (arthroscopy, shoulder, surgical; with lysis and resection of adhesions, with or without manipulation), 29826 (arthroscopy, shoulder, surgical; decompression of subacromial space with partial acromioplasty, with or without coracoacromial release), and 29827 (arthroscopy, shoulder, surgical; with rotator cuff repair).

For analysis, we divided the data into total number of arthroscopic shoulder procedures performed by each surgeon each year and number of LHB tenodesis procedures performed by each surgeon each year. Total number of patients who had an arthroscopic procedure was used to create a denominator, and number of LHB tenodesis procedures showed the percentage of arthroscopic shoulder surgery patients who underwent LHB tenodesis. (All patients who undergo biceps tenodesis also have, at the least, diagnostic shoulder arthroscopy with or without tenotomy; if the tendon is ruptured, tenotomy is unnecessary.)

Descriptive statistics were calculated as means (SDs) for continuous variables and as frequencies with percentages for categorical variables. Linear regression analysis was used to determine whether the number of LHB tenodesis procedures changed during the study period and whether patient age changed over time. Significance was set at P < .05.

Results

Of the 7640 patients who underwent arthroscopic shoulder procedures between 2004 and 2014, 2125 had LHB tenodesis (CPT code 23430).

Discussion

Tenodesis has become a common treatment option for several pathologic shoulder conditions involving the LHB tendon.⁵ We set out to determine trends in LHB tenodesis at a subspecialty-focused shoulder orthopedic practice and hypothesized that the rate of LHB tenodesis would increase significantly over time and that there would be no significant change in the age of patients who underwent LHB tenodesis. Our hypotheses were confirmed: The number of LHB tenodesis cases increased significantly without a significant change in patient age.

Treatment options for LHB pathology and SLAP tears include simple tenotomy, débridement, open biceps tenodesis, and arthroscopic tenodesis.^11,12,15

Am J Orthop. 2017;46(4):E219-E223. Copyright Frontline Medical Communications Inc. 2017. All rights reserved.

Take-Home Points

• According to the orthopedic literature, ST and LTO for a TSA produce excellent clinical outcomes, and technique selection should be based on surgeon discretion and expertise.
• Compared with the LTO approach, the ST approach produced significantly more forward elevation improvement and trended toward more external rotation and abduction and fewer revisions.
• ST and LTO approaches for a TSA result in similar Constant scores, pain scores, radiographic outcomes, and complication rates.

During total shoulder arthroplasty (TSA) exposure, the subscapularis muscle must be mobilized; its repair is crucial to the stability of the arthroplasty. The subscapularis is the largest rotator cuff muscle and has a contractile force equal to that of the other 3 muscles combined.^1,2 Traditionally it is mobilized with a tenotomy just medial to the tendon’s insertion onto the lesser tuberosity. Over the past 15 years, however, numerous authors have reported dysfunction after subscapularis tenotomy (ST). In 2003, Miller and colleagues³ reported that, at 2-year follow-up, almost 70% of patients had abnormal belly-press and liftoff tests, surrogate markers of subscapularis function. Other authors have found increased rates of anterior instability after subscapularis rupture.^4,5

In 2005, Gerber and colleagues⁶ introduced a technique for circumventing surgical division of the subscapularis. They described a lesser tuberosity osteotomy (LTO), in which the subscapularis tendon is detached with a bone fragment 5 mm to 10 mm in thickness and 3 cm to 4 cm in length. This approach was based on the premise that bone-to-bone healing is more reliable than tendon-to-tendon healing. Initial studies reported successful osteotomy healing, improved clinical outcome scores, and fewer abnormalities with belly-press and liftoff tests.^2,6 More recent literature, however, has questioned the necessity of LTO.^2,4,7-9We performed a systematic review to evaluate the literature, describe ST and LTO, and summarize the radiographic and clinical outcomes of both techniques. We hypothesized there would be no significant clinical differences between these approaches.

Methods

Search Strategy and Study Selection

Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we systematically reviewed the literature.¹⁰ Searches were completed in September 2014 using the PubMed Medline database and the Cochrane Central Register of Clinical Trials. Two reviewers (Dr. Louie, Dr. Levy) independently performed the search and assessed eligibility of all relevant studies based on predetermined inclusion criteria. Disagreements between reviewers were resolved by discussion. Key word selection was designed to capture all English-language studies with clinical and/or radiographic outcomes and level I to IV evidence. We used an electronic search algorithm with key words and a series of NOT phrases to match certain exclusion criteria:

(((((((((((((((((((((((((((((((((((((total[Text Word]) AND shoulder[Title]) AND arthroplasty[Title] AND (English[lang]))) NOT reverse[Title/Abstract]) NOT hemiarthroplasty[Title]) NOT nonoperative[Title]) NOT nonsurgical[Title] AND (English[lang]))) NOT rheumatoid[Title/Abstract]) NOT inflammatory[Title/Abstract]) NOT elbow[Title/Abstract]) NOT wrist[Title/Abstract]) NOT hip[Title/Abstract]) NOT knee[Title/Abstract]) NOT ankle[Title/Abstract] AND (English[lang]))) NOT biomechanic[Title/Abstract]) NOT biomechanics[Title/Abstract]) NOT biomechanical [Title/Abstract]) NOT cadaveric[Title/Abstract]) NOT revision[Title]) NOT resurfacing[Title/Abstract]) NOT surface[Title/Abstract]) NOT interphalangeal[Title/Abstract] AND (English[lang]))) NOT radiostereometric[Title/Abstract] AND (English[lang]))) NOT cmc[Title/Abstract]) NOT carpometacarpal[Title/Abstract]) NOT cervical[Title/Abstract]) NOT histology[Title/Abstract]) NOT histological[Title/Abstract]) NOT collagen[Title/Abstract] AND (English[lang]))) NOT kinematic[Title/Abstract]) NOT kinematics[Title/Abstract] AND (English[lang]))) NOT vitro[Title/Abstract] AND (English[lang]))) NOT inverted[Title/Abstract]) NOT grammont[Title/Abstract]) NOT arthrodesis[Title/Abstract]) NOT fusion[Title/Abstract]) NOT reverse[Title/Abstract] AND (English[lang]))

Study exclusion criteria consisted of cadaveric, biomechanical, histologic, and kinematic results as well as analyses of nonoperative management, hemiarthroplasty, or reverse TSA. Studies were excluded if they did not report clinical and/or radiographic data. Minimum mean follow-up was 2 years. To discount the effect of other TSA technical innovations, we evaluated the same period for the 2 surgical approaches. The first study with clinical outcomes after LTO was published in early 2005,⁶ so all studies published before 2005 were excluded.

We reviewed all references within the studies included by the initial search algorithm: randomized control trials, retrospective and prospective cohort designs, case series, and treatment studies. Technical notes, review papers, letters to the editor, and level V evidence reviews were excluded. To avoid counting patients twice, we compared each study’s authors and data collection period with those of the other studies. If there was overlap in authorship, period, and place, only the study with the longer follow-up or more comprehensive data was included. All trials comparing ST and LTO were included. If the authors of a TSA study did not describe the approach used, that study was excluded from our review.

Data Extraction

We collected details of study design, sample size, and patient demographics (sex, age, hand dominance, primary diagnosis). We also abstracted surgical factors about the glenoid component (cemented vs uncemented; pegged vs keeled; all-polyethylene vs metal-backed) and the humeral component (cemented vs press-fit; stemmed vs stemless). Clinical outcomes included pain scores, functional scores, number of revisions, range of motion (ROM), and subscapularis-specific tests (eg, belly-press, liftoff). As pain scales varied between studies, all values were converted to a 10-point scoring scale (0 = no pain; 10 = maximum pain) for comparisons. Numerous functional outcome scores were reported, but the Constant score was the only one consistently used across studies, making it a good choice for comparisons. One study used Penn Shoulder Scores (PSSs) and directly compared ST and LTO groups, so its data were included. In addition, radiographic data were compiled: radiolucencies around the humeral stem and glenoid component, humeral head subluxation/migration, and osteotomy healing. The only consistent radiographic parameter available for comparisons between groups was the presence of radiolucencies.

The Modified Coleman Methodology Score (MCMS), described by Cowan and colleagues,¹¹ was used to evaluate the methodologic quality of each study. The MCMS is a 15-item instrument that has been used to assess both randomized and nonrandomized trials.^12,13 It has a scaled score ranging from 0 to 100 (85-100, excellent; 70-84, good; 55-69, fair; <55, poor). Study quality was not factored into the data synthesis analysis.

Statistical Analysis

Data are reported as weighted means and standard deviations. A mean was calculated for each study reporting on a respective data point and was then weighed according to the study sample size. The result was that the nonweighted means from studies with smaller samples did not carry as much weight as those from studies with larger samples. Student t tests and 2-way analysis of variance were used to compare the ST and LTO groups and assess differences over time (SPSS Version 18; IBM). An α of 0.05 was set as statistically significant.

Results

Twenty studies (1420 shoulders, 1392 patients) were included in the final dataset (Figure).^2,6,8,14-30 

The youngest patients in the ST and LTO groups were 22 years and 19 years of age, respectively.

Discussion

Our goal in this systematic review was to analyze outcomes associated with ST and LTO in a heterogenous TSA population. We hypothesized TSA with ST or LTO would produce similar clinical and radiographic outcomes. There were no significant differences in Constant scores, pain scores, radiolucencies, or complications between the 2 groups. The ST group showed trends toward wider ROM improvements and fewer revisions, but only the change in forward elevation was significant. The components used in the 2 groups were similar with the exception of a lack of keeled glenoids and cemented humeral stems in the LTO group; data stratification controlling for these differences revealed no change in outcomes.

The optimal method of subscapularis mobilization for TSA remains a source of debate. Jackson and colleagues²³ found significant improvements in Neer and DASH scores after ST. However, 7 of 15 patients ruptured the subscapularis after 6 months and had significantly lower DASH scores. In 2005, Gerber and colleagues⁶ first described the LTO technique as an alternative to ST. After a mean of 39 months, 89% of their patients had a negative belly-press test, and 75% had a normal liftoff test. Radiographic evaluation revealed that the osteotomized fragment had healed in an anatomical position in all shoulders. In a large case series, Small and colleagues²⁰ used radiographs and computed tomography to further investigate LTO healing rates and found that 89% of patients had bony union by 6 months and that smoking was a significant risk factor for nonunion.

Biomechanical studies comparing ST and LTO approaches have shown mixed results. Ponce and colleagues² found decreased cyclic displacement and increased maximum load to failure with LTO, but Giuseffi and colleagues³² showed less cyclic displacement with ST and no difference in load to failure. Others authors have found no significant differences in stiffness or maximum load to failure.³³ Van den Berghe and colleagues⁷ reported a higher failure rate in bone-to-bone repairs compared with tendon-to-tendon constructs. Moreover, they found that suture cut-out through bone tunnels is the primary mode of LTO failure, so many LTO surgeons now pass sutures around the humeral stem instead.

Three TSA studies directly compared ST and LTO approaches. Buckley and colleagues¹⁴ analyzed 60 TSAs and found no significant differences in WOOS, DASH, or Constant scores between groups. The authors described an ST subgroup with subscapularis attenuation on ultrasound but did not report the group as having any inferior functional outcome. Scalise and colleagues¹⁵ showed improved strength and PSSs in both groups after 2 years. However, the LTO group had a lower rate of subscapularis tears and significantly higher PSSs. Finally, Jandhyala and colleagues¹⁶ reported more favorable outcomes with LTO, which trended toward wider ROM and significantly higher belly-press test grades. Lapner and colleagues³⁴ conducted a randomized, controlled trial (often referenced) and found no significant differences between the 2 groups in terms of strength or functional outcome at 2-year follow-up. Their study, however, included hemiarthroplasties and did not substratify the TSA population, so we did not include it in our review.

Our systematic review found significantly more forward elevation improvement for the ST group than the LTO group, which may suggest improved ROM with a soft-tissue approach than a bony approach. At the same time, the ST group trended toward better passive external rotation relative to the LTO group. This trend indicates fewer constraints to external rotation in the ST group, possibly attributable to a more attenuated subscapularis after tenotomy. Subscapularis tear or attenuation was more commonly reported in the ST group than in the LTO group, though not significantly so. This may indicate that more ST studies than LTO studies specially emphasized postoperative subscapularis function, but these data also highlight some authors’ concerns regarding subscapularis dysfunction after tenotomy.^6,15,16The study populations’ complication rates were similar, just over 17%. The LTO group trended toward a higher revision rate, but it was not statistically significant. The LTO group also had significantly fewer patients with osteoarthritis and more patients with posttraumatic arthritis, so this group may have had more complex patients predisposed to a higher likelihood of revision surgery. Revisions were most commonly performed for aseptic loosening; theoretically, if osteotomies heal less effectively than tenotomies, the LTO approach could produce component instability and aseptic loosening. However, no prior studies or other clinical findings from this review suggest LTO predisposes to aseptic loosening. Overall, the uneven revision rates represent a clinical concern that should be monitored as larger samples of patients undergo ST and LTO procedures.

Glenoid radiolucencies were the only radiographic parameter consistently reported in the included studies. Twelve ST studies had radiolucency data—compared with only 2 LTO studies. Thus, our ability to compare radiographic outcomes was limited. Our data revealed similar rates of glenoid radiolucencies between the 2 approaches. The clinical relevance of radiolucencies is questioned by some authors, and, indeed, Razmjou and colleagues²⁵ found no correlation of radiolucencies with patient satisfaction. Nevertheless, early presence of radiolucencies may raise concerns about progressive loss of fixation,^35,36 so this should be monitored.

Limitations of this systematic review reflect the studies analyzed. We minimized selection bias by including level I to IV evidence, but most studies were level IV, and only 1 was level I. As such, there was a relative paucity of consistent clinical and radiographic data. For instance, although many ST studies reported patient satisfaction as an outcomes measure, only 1 LTO study commented on it. Perhaps the relative novelty of the LTO approach has prompted some authors to focus more on technical details and less on reporting a variety of outcome measures. As mentioned earlier, the significance of radiolucency data is controversial, and determination of their presence or absence depends on the observer. A radiolucency found in one study may not qualify as one in a study that uses different criteria. However, lucency data were the most frequently and reliably reported radiographic parameter, so we deemed it the most appropriate method for comparing radiographic outcomes. Finally, the baseline differences in diagnosis between the ST and LTO groups complicated comparisons. We stratified the groups by component design because use of keeled or pegged implants or humeral cemented or press-fit stems was usually a uniform feature of each study—enabling removal of certain studies for data stratification. However, we were unable to stratify by original diagnosis because these groups were not stratified within the individual studies.

Conclusion

Our systematic review found similar Constant scores, pain scores, radiographic outcomes, and complication rates for the ST and LTO approaches. Compared with the LTO approach, the ST approach produced significantly more forward elevation improvement and trended toward more external rotation and abduction and fewer revisions. Although not definitive, these data suggest the ST approach may provide more stability over the long term, but additional comprehensive studies are needed to increase the sample size and the power of the trends elucidated in this review. According to the orthopedic literature, both techniques produce excellent clinical outcomes, and technique selection should be based on surgeon discretion and expertise.

Am J Orthop. 2017;46(2):E131-E138. Copyright Frontline Medical Communications Inc. 2017. All rights reserved.

Take-Home Points

• According to the orthopedic literature, ST and LTO for a TSA produce excellent clinical outcomes, and technique selection should be based on surgeon discretion and expertise.
• Compared with the LTO approach, the ST approach produced significantly more forward elevation improvement and trended toward more external rotation and abduction and fewer revisions.
• ST and LTO approaches for a TSA result in similar Constant scores, pain scores, radiographic outcomes, and complication rates.

During total shoulder arthroplasty (TSA) exposure, the subscapularis muscle must be mobilized; its repair is crucial to the stability of the arthroplasty. The subscapularis is the largest rotator cuff muscle and has a contractile force equal to that of the other 3 muscles combined.^1,2 Traditionally it is mobilized with a tenotomy just medial to the tendon’s insertion onto the lesser tuberosity. Over the past 15 years, however, numerous authors have reported dysfunction after subscapularis tenotomy (ST). In 2003, Miller and colleagues³ reported that, at 2-year follow-up, almost 70% of patients had abnormal belly-press and liftoff tests, surrogate markers of subscapularis function. Other authors have found increased rates of anterior instability after subscapularis rupture.^4,5

In 2005, Gerber and colleagues⁶ introduced a technique for circumventing surgical division of the subscapularis. They described a lesser tuberosity osteotomy (LTO), in which the subscapularis tendon is detached with a bone fragment 5 mm to 10 mm in thickness and 3 cm to 4 cm in length. This approach was based on the premise that bone-to-bone healing is more reliable than tendon-to-tendon healing. Initial studies reported successful osteotomy healing, improved clinical outcome scores, and fewer abnormalities with belly-press and liftoff tests.^2,6 More recent literature, however, has questioned the necessity of LTO.^2,4,7-9We performed a systematic review to evaluate the literature, describe ST and LTO, and summarize the radiographic and clinical outcomes of both techniques. We hypothesized there would be no significant clinical differences between these approaches.

Methods

Search Strategy and Study Selection

Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we systematically reviewed the literature.¹⁰ Searches were completed in September 2014 using the PubMed Medline database and the Cochrane Central Register of Clinical Trials. Two reviewers (Dr. Louie, Dr. Levy) independently performed the search and assessed eligibility of all relevant studies based on predetermined inclusion criteria. Disagreements between reviewers were resolved by discussion. Key word selection was designed to capture all English-language studies with clinical and/or radiographic outcomes and level I to IV evidence. We used an electronic search algorithm with key words and a series of NOT phrases to match certain exclusion criteria:

(((((((((((((((((((((((((((((((((((((total[Text Word]) AND shoulder[Title]) AND arthroplasty[Title] AND (English[lang]))) NOT reverse[Title/Abstract]) NOT hemiarthroplasty[Title]) NOT nonoperative[Title]) NOT nonsurgical[Title] AND (English[lang]))) NOT rheumatoid[Title/Abstract]) NOT inflammatory[Title/Abstract]) NOT elbow[Title/Abstract]) NOT wrist[Title/Abstract]) NOT hip[Title/Abstract]) NOT knee[Title/Abstract]) NOT ankle[Title/Abstract] AND (English[lang]))) NOT biomechanic[Title/Abstract]) NOT biomechanics[Title/Abstract]) NOT biomechanical [Title/Abstract]) NOT cadaveric[Title/Abstract]) NOT revision[Title]) NOT resurfacing[Title/Abstract]) NOT surface[Title/Abstract]) NOT interphalangeal[Title/Abstract] AND (English[lang]))) NOT radiostereometric[Title/Abstract] AND (English[lang]))) NOT cmc[Title/Abstract]) NOT carpometacarpal[Title/Abstract]) NOT cervical[Title/Abstract]) NOT histology[Title/Abstract]) NOT histological[Title/Abstract]) NOT collagen[Title/Abstract] AND (English[lang]))) NOT kinematic[Title/Abstract]) NOT kinematics[Title/Abstract] AND (English[lang]))) NOT vitro[Title/Abstract] AND (English[lang]))) NOT inverted[Title/Abstract]) NOT grammont[Title/Abstract]) NOT arthrodesis[Title/Abstract]) NOT fusion[Title/Abstract]) NOT reverse[Title/Abstract] AND (English[lang]))

Study exclusion criteria consisted of cadaveric, biomechanical, histologic, and kinematic results as well as analyses of nonoperative management, hemiarthroplasty, or reverse TSA. Studies were excluded if they did not report clinical and/or radiographic data. Minimum mean follow-up was 2 years. To discount the effect of other TSA technical innovations, we evaluated the same period for the 2 surgical approaches. The first study with clinical outcomes after LTO was published in early 2005,⁶ so all studies published before 2005 were excluded.

We reviewed all references within the studies included by the initial search algorithm: randomized control trials, retrospective and prospective cohort designs, case series, and treatment studies. Technical notes, review papers, letters to the editor, and level V evidence reviews were excluded. To avoid counting patients twice, we compared each study’s authors and data collection period with those of the other studies. If there was overlap in authorship, period, and place, only the study with the longer follow-up or more comprehensive data was included. All trials comparing ST and LTO were included. If the authors of a TSA study did not describe the approach used, that study was excluded from our review.

Data Extraction

We collected details of study design, sample size, and patient demographics (sex, age, hand dominance, primary diagnosis). We also abstracted surgical factors about the glenoid component (cemented vs uncemented; pegged vs keeled; all-polyethylene vs metal-backed) and the humeral component (cemented vs press-fit; stemmed vs stemless). Clinical outcomes included pain scores, functional scores, number of revisions, range of motion (ROM), and subscapularis-specific tests (eg, belly-press, liftoff). As pain scales varied between studies, all values were converted to a 10-point scoring scale (0 = no pain; 10 = maximum pain) for comparisons. Numerous functional outcome scores were reported, but the Constant score was the only one consistently used across studies, making it a good choice for comparisons. One study used Penn Shoulder Scores (PSSs) and directly compared ST and LTO groups, so its data were included. In addition, radiographic data were compiled: radiolucencies around the humeral stem and glenoid component, humeral head subluxation/migration, and osteotomy healing. The only consistent radiographic parameter available for comparisons between groups was the presence of radiolucencies.

The Modified Coleman Methodology Score (MCMS), described by Cowan and colleagues,¹¹ was used to evaluate the methodologic quality of each study. The MCMS is a 15-item instrument that has been used to assess both randomized and nonrandomized trials.^12,13 It has a scaled score ranging from 0 to 100 (85-100, excellent; 70-84, good; 55-69, fair; <55, poor). Study quality was not factored into the data synthesis analysis.

Statistical Analysis

Data are reported as weighted means and standard deviations. A mean was calculated for each study reporting on a respective data point and was then weighed according to the study sample size. The result was that the nonweighted means from studies with smaller samples did not carry as much weight as those from studies with larger samples. Student t tests and 2-way analysis of variance were used to compare the ST and LTO groups and assess differences over time (SPSS Version 18; IBM). An α of 0.05 was set as statistically significant.

Results

Twenty studies (1420 shoulders, 1392 patients) were included in the final dataset (Figure).^2,6,8,14-30 

The youngest patients in the ST and LTO groups were 22 years and 19 years of age, respectively.

Discussion

Our goal in this systematic review was to analyze outcomes associated with ST and LTO in a heterogenous TSA population. We hypothesized TSA with ST or LTO would produce similar clinical and radiographic outcomes. There were no significant differences in Constant scores, pain scores, radiolucencies, or complications between the 2 groups. The ST group showed trends toward wider ROM improvements and fewer revisions, but only the change in forward elevation was significant. The components used in the 2 groups were similar with the exception of a lack of keeled glenoids and cemented humeral stems in the LTO group; data stratification controlling for these differences revealed no change in outcomes.

The optimal method of subscapularis mobilization for TSA remains a source of debate. Jackson and colleagues²³ found significant improvements in Neer and DASH scores after ST. However, 7 of 15 patients ruptured the subscapularis after 6 months and had significantly lower DASH scores. In 2005, Gerber and colleagues⁶ first described the LTO technique as an alternative to ST. After a mean of 39 months, 89% of their patients had a negative belly-press test, and 75% had a normal liftoff test. Radiographic evaluation revealed that the osteotomized fragment had healed in an anatomical position in all shoulders. In a large case series, Small and colleagues²⁰ used radiographs and computed tomography to further investigate LTO healing rates and found that 89% of patients had bony union by 6 months and that smoking was a significant risk factor for nonunion.

Biomechanical studies comparing ST and LTO approaches have shown mixed results. Ponce and colleagues² found decreased cyclic displacement and increased maximum load to failure with LTO, but Giuseffi and colleagues³² showed less cyclic displacement with ST and no difference in load to failure. Others authors have found no significant differences in stiffness or maximum load to failure.³³ Van den Berghe and colleagues⁷ reported a higher failure rate in bone-to-bone repairs compared with tendon-to-tendon constructs. Moreover, they found that suture cut-out through bone tunnels is the primary mode of LTO failure, so many LTO surgeons now pass sutures around the humeral stem instead.

Three TSA studies directly compared ST and LTO approaches. Buckley and colleagues¹⁴ analyzed 60 TSAs and found no significant differences in WOOS, DASH, or Constant scores between groups. The authors described an ST subgroup with subscapularis attenuation on ultrasound but did not report the group as having any inferior functional outcome. Scalise and colleagues¹⁵ showed improved strength and PSSs in both groups after 2 years. However, the LTO group had a lower rate of subscapularis tears and significantly higher PSSs. Finally, Jandhyala and colleagues¹⁶ reported more favorable outcomes with LTO, which trended toward wider ROM and significantly higher belly-press test grades. Lapner and colleagues³⁴ conducted a randomized, controlled trial (often referenced) and found no significant differences between the 2 groups in terms of strength or functional outcome at 2-year follow-up. Their study, however, included hemiarthroplasties and did not substratify the TSA population, so we did not include it in our review.

Our systematic review found significantly more forward elevation improvement for the ST group than the LTO group, which may suggest improved ROM with a soft-tissue approach than a bony approach. At the same time, the ST group trended toward better passive external rotation relative to the LTO group. This trend indicates fewer constraints to external rotation in the ST group, possibly attributable to a more attenuated subscapularis after tenotomy. Subscapularis tear or attenuation was more commonly reported in the ST group than in the LTO group, though not significantly so. This may indicate that more ST studies than LTO studies specially emphasized postoperative subscapularis function, but these data also highlight some authors’ concerns regarding subscapularis dysfunction after tenotomy.^6,15,16The study populations’ complication rates were similar, just over 17%. The LTO group trended toward a higher revision rate, but it was not statistically significant. The LTO group also had significantly fewer patients with osteoarthritis and more patients with posttraumatic arthritis, so this group may have had more complex patients predisposed to a higher likelihood of revision surgery. Revisions were most commonly performed for aseptic loosening; theoretically, if osteotomies heal less effectively than tenotomies, the LTO approach could produce component instability and aseptic loosening. However, no prior studies or other clinical findings from this review suggest LTO predisposes to aseptic loosening. Overall, the uneven revision rates represent a clinical concern that should be monitored as larger samples of patients undergo ST and LTO procedures.

Glenoid radiolucencies were the only radiographic parameter consistently reported in the included studies. Twelve ST studies had radiolucency data—compared with only 2 LTO studies. Thus, our ability to compare radiographic outcomes was limited. Our data revealed similar rates of glenoid radiolucencies between the 2 approaches. The clinical relevance of radiolucencies is questioned by some authors, and, indeed, Razmjou and colleagues²⁵ found no correlation of radiolucencies with patient satisfaction. Nevertheless, early presence of radiolucencies may raise concerns about progressive loss of fixation,^35,36 so this should be monitored.

Limitations of this systematic review reflect the studies analyzed. We minimized selection bias by including level I to IV evidence, but most studies were level IV, and only 1 was level I. As such, there was a relative paucity of consistent clinical and radiographic data. For instance, although many ST studies reported patient satisfaction as an outcomes measure, only 1 LTO study commented on it. Perhaps the relative novelty of the LTO approach has prompted some authors to focus more on technical details and less on reporting a variety of outcome measures. As mentioned earlier, the significance of radiolucency data is controversial, and determination of their presence or absence depends on the observer. A radiolucency found in one study may not qualify as one in a study that uses different criteria. However, lucency data were the most frequently and reliably reported radiographic parameter, so we deemed it the most appropriate method for comparing radiographic outcomes. Finally, the baseline differences in diagnosis between the ST and LTO groups complicated comparisons. We stratified the groups by component design because use of keeled or pegged implants or humeral cemented or press-fit stems was usually a uniform feature of each study—enabling removal of certain studies for data stratification. However, we were unable to stratify by original diagnosis because these groups were not stratified within the individual studies.

Conclusion

Our systematic review found similar Constant scores, pain scores, radiographic outcomes, and complication rates for the ST and LTO approaches. Compared with the LTO approach, the ST approach produced significantly more forward elevation improvement and trended toward more external rotation and abduction and fewer revisions. Although not definitive, these data suggest the ST approach may provide more stability over the long term, but additional comprehensive studies are needed to increase the sample size and the power of the trends elucidated in this review. According to the orthopedic literature, both techniques produce excellent clinical outcomes, and technique selection should be based on surgeon discretion and expertise.

Am J Orthop. 2017;46(2):E131-E138. Copyright Frontline Medical Communications Inc. 2017. All rights reserved.

Take-Home Points

• According to the orthopedic literature, ST and LTO for a TSA produce excellent clinical outcomes, and technique selection should be based on surgeon discretion and expertise.
• Compared with the LTO approach, the ST approach produced significantly more forward elevation improvement and trended toward more external rotation and abduction and fewer revisions.
• ST and LTO approaches for a TSA result in similar Constant scores, pain scores, radiographic outcomes, and complication rates.

During total shoulder arthroplasty (TSA) exposure, the subscapularis muscle must be mobilized; its repair is crucial to the stability of the arthroplasty. The subscapularis is the largest rotator cuff muscle and has a contractile force equal to that of the other 3 muscles combined.^1,2 Traditionally it is mobilized with a tenotomy just medial to the tendon’s insertion onto the lesser tuberosity. Over the past 15 years, however, numerous authors have reported dysfunction after subscapularis tenotomy (ST). In 2003, Miller and colleagues³ reported that, at 2-year follow-up, almost 70% of patients had abnormal belly-press and liftoff tests, surrogate markers of subscapularis function. Other authors have found increased rates of anterior instability after subscapularis rupture.^4,5

In 2005, Gerber and colleagues⁶ introduced a technique for circumventing surgical division of the subscapularis. They described a lesser tuberosity osteotomy (LTO), in which the subscapularis tendon is detached with a bone fragment 5 mm to 10 mm in thickness and 3 cm to 4 cm in length. This approach was based on the premise that bone-to-bone healing is more reliable than tendon-to-tendon healing. Initial studies reported successful osteotomy healing, improved clinical outcome scores, and fewer abnormalities with belly-press and liftoff tests.^2,6 More recent literature, however, has questioned the necessity of LTO.^2,4,7-9We performed a systematic review to evaluate the literature, describe ST and LTO, and summarize the radiographic and clinical outcomes of both techniques. We hypothesized there would be no significant clinical differences between these approaches.

Methods

Search Strategy and Study Selection

Using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we systematically reviewed the literature.¹⁰ Searches were completed in September 2014 using the PubMed Medline database and the Cochrane Central Register of Clinical Trials. Two reviewers (Dr. Louie, Dr. Levy) independently performed the search and assessed eligibility of all relevant studies based on predetermined inclusion criteria. Disagreements between reviewers were resolved by discussion. Key word selection was designed to capture all English-language studies with clinical and/or radiographic outcomes and level I to IV evidence. We used an electronic search algorithm with key words and a series of NOT phrases to match certain exclusion criteria:

(((((((((((((((((((((((((((((((((((((total[Text Word]) AND shoulder[Title]) AND arthroplasty[Title] AND (English[lang]))) NOT reverse[Title/Abstract]) NOT hemiarthroplasty[Title]) NOT nonoperative[Title]) NOT nonsurgical[Title] AND (English[lang]))) NOT rheumatoid[Title/Abstract]) NOT inflammatory[Title/Abstract]) NOT elbow[Title/Abstract]) NOT wrist[Title/Abstract]) NOT hip[Title/Abstract]) NOT knee[Title/Abstract]) NOT ankle[Title/Abstract] AND (English[lang]))) NOT biomechanic[Title/Abstract]) NOT biomechanics[Title/Abstract]) NOT biomechanical [Title/Abstract]) NOT cadaveric[Title/Abstract]) NOT revision[Title]) NOT resurfacing[Title/Abstract]) NOT surface[Title/Abstract]) NOT interphalangeal[Title/Abstract] AND (English[lang]))) NOT radiostereometric[Title/Abstract] AND (English[lang]))) NOT cmc[Title/Abstract]) NOT carpometacarpal[Title/Abstract]) NOT cervical[Title/Abstract]) NOT histology[Title/Abstract]) NOT histological[Title/Abstract]) NOT collagen[Title/Abstract] AND (English[lang]))) NOT kinematic[Title/Abstract]) NOT kinematics[Title/Abstract] AND (English[lang]))) NOT vitro[Title/Abstract] AND (English[lang]))) NOT inverted[Title/Abstract]) NOT grammont[Title/Abstract]) NOT arthrodesis[Title/Abstract]) NOT fusion[Title/Abstract]) NOT reverse[Title/Abstract] AND (English[lang]))

Study exclusion criteria consisted of cadaveric, biomechanical, histologic, and kinematic results as well as analyses of nonoperative management, hemiarthroplasty, or reverse TSA. Studies were excluded if they did not report clinical and/or radiographic data. Minimum mean follow-up was 2 years. To discount the effect of other TSA technical innovations, we evaluated the same period for the 2 surgical approaches. The first study with clinical outcomes after LTO was published in early 2005,⁶ so all studies published before 2005 were excluded.

We reviewed all references within the studies included by the initial search algorithm: randomized control trials, retrospective and prospective cohort designs, case series, and treatment studies. Technical notes, review papers, letters to the editor, and level V evidence reviews were excluded. To avoid counting patients twice, we compared each study’s authors and data collection period with those of the other studies. If there was overlap in authorship, period, and place, only the study with the longer follow-up or more comprehensive data was included. All trials comparing ST and LTO were included. If the authors of a TSA study did not describe the approach used, that study was excluded from our review.

Data Extraction

We collected details of study design, sample size, and patient demographics (sex, age, hand dominance, primary diagnosis). We also abstracted surgical factors about the glenoid component (cemented vs uncemented; pegged vs keeled; all-polyethylene vs metal-backed) and the humeral component (cemented vs press-fit; stemmed vs stemless). Clinical outcomes included pain scores, functional scores, number of revisions, range of motion (ROM), and subscapularis-specific tests (eg, belly-press, liftoff). As pain scales varied between studies, all values were converted to a 10-point scoring scale (0 = no pain; 10 = maximum pain) for comparisons. Numerous functional outcome scores were reported, but the Constant score was the only one consistently used across studies, making it a good choice for comparisons. One study used Penn Shoulder Scores (PSSs) and directly compared ST and LTO groups, so its data were included. In addition, radiographic data were compiled: radiolucencies around the humeral stem and glenoid component, humeral head subluxation/migration, and osteotomy healing. The only consistent radiographic parameter available for comparisons between groups was the presence of radiolucencies.

The Modified Coleman Methodology Score (MCMS), described by Cowan and colleagues,¹¹ was used to evaluate the methodologic quality of each study. The MCMS is a 15-item instrument that has been used to assess both randomized and nonrandomized trials.^12,13 It has a scaled score ranging from 0 to 100 (85-100, excellent; 70-84, good; 55-69, fair; <55, poor). Study quality was not factored into the data synthesis analysis.

Statistical Analysis

Data are reported as weighted means and standard deviations. A mean was calculated for each study reporting on a respective data point and was then weighed according to the study sample size. The result was that the nonweighted means from studies with smaller samples did not carry as much weight as those from studies with larger samples. Student t tests and 2-way analysis of variance were used to compare the ST and LTO groups and assess differences over time (SPSS Version 18; IBM). An α of 0.05 was set as statistically significant.

Results

Twenty studies (1420 shoulders, 1392 patients) were included in the final dataset (Figure).^2,6,8,14-30 

The youngest patients in the ST and LTO groups were 22 years and 19 years of age, respectively.