The Volume-Value Relationship in Shoulder Arthroplasty

Impact of Surgeon Case Volume on Outcomes After Reverse Total Shoulder Arthroplasty

INTRODUCTION

Despite a rapid increase in utilization of reverse total shoulder arthroplasty (rTSA), volume-outcome studies focusing on surgeon volume are lacking. Surgeon-specific volume-outcome studies may inform policymakers and provide insight into learning curves and measures of efficiency with greater case volume.

METHODS

This retrospective cohort study with longitudinal data included all rTSA cases as recorded in the Centers for Medicare & Medicaid Services Limited Data Set (2016 to 2018). The main effect was surgeon volume; this was categorized using two measures of surgeon volume: (1) rTSA case volume and (2) rTSA + TSA case volume. Volume cutoff values were calculated by applying a stratum-specific likelihood ratio analysis.

RESULTS

Among 90,318 rTSA cases performed by 7,097 surgeons, we found a mean annual rTSA surgeon volume of 6 ± 10 and a mean rTSA + TSA volume of 9 ± 14. Regression models using surgeon-specific rTSA volume revealed that surgery from low (<29 cases) compared with medium (29 to 96 cases) rTSA-volume surgeons was associated with a significantly higher 90-day all-cause readmission (odds ratio [OR], 1.17; confidence interval [CI], 1.10 to 1.25; P < 0.0001), higher 90-day readmission rates because of an infection (OR, 1.46; CI, 1.16 to 1.83; P = 0.0013) or dislocation (OR, 1.43; CI, 1.19 to 1.72; P = 0.0001), increased 90-day postoperative cost (+11.3% CI, 4.2% to 19.0%; P = 0.0016), and a higher transfusion rate (OR, 2.06; CI, 1.70 to 2.50; P < 0.0001). Similar patterns existed when using categorizations based on rTSA + TSA case volume.

CONCLUSION

Surgeon-specific volume-outcome relationships exist in this rTSA cohort, and we were able to identify thresholds that may identify low and medium/high volume surgeons. Observed volume-outcome relationships were independent of the definition of surgeon volume applied: either by focusing on the number of rTSAs performed per surgeon or anatomic TSAs performed.

LEVEL OF EVIDENCE

III.

An Analysis of Shoulder Surgeon Volume on Surgeon Competency, Hospital Costs, and Adverse Events: A Systematic Review

Purpose

The purpose of this systematic review is to assess the impact of shoulder surgeon volume of common shoulder procedures on hospital/surgeon efficiency, adverse events, and hospital costs.

Methods

Four online databases (PubMed, Embase, MEDLINE, and CENTRAL) were searched for literature on the influence of surgeon volume on outcomes for shoulder surgery, from data inception to October 1, 2020. The Methodological Index for Non-Randomized Studies tool was used to assess study quality. Data are presented descriptively.

Results

Twelve studies encompassing 150,898 patients were included in this review. The distribution of surgery type was rotator cuff repair (53.7%; n = 81,066), shoulder arthroplasty (35.7%; n = 53,833), and ORIF (10.6%; n = 15,999). Higher surgeon volume for rotator cuff repairs was associated with lower surgical time, length of stay, costs, and reoperation/readmission rates. For shoulder arthroplasty, higher surgeon volume was associated with lower length of stay, costs, surgical time, non-routine disposition, blood loss, reoperation/readmission, and complications. As for ORIF, higher surgeon volume was associated with lower length of stay, costs, and complications.

Conclusion

A high surgical volume leads to improved results for hospital/surgeon efficiency and reduces adverse events and hospital costs across various orthopaedic procedures. Hospitals and physicians can use this information to develop and adhere to policies and practices that contribute to more efficient and better-quality care for patients.

Level of Evidence

III.

Association Between Limited English Language Proficiency and Disparities in Length of Stay and Discharge Disposition After Total Shoulder Arthroplasty: A Retrospective Cohort Study

Background: Limited English language proficiency in patients undergoing total shoulder arthroplasty (TSA) may make treatment more challenging. Purpose: We sought to investigate the potential association between TSA patients' use of a language interpreter and 2 outcomes: hospital length of stay (LOS) and discharge disposition. Methods: We conducted a retrospective cohort study comparing LOS and discharge disposition after TSA for patients who required interpreter services and patients who did not at a single institution in an urban setting between 2016 and 2020. Consecutive patients requiring interpreter services who underwent TSA were matched 1:1 to patients who did not require an interpreter by age, body mass index (BMI), sex, and procedure. Multivariate regression models controlling for age, BMI, sex, smoking, opioid use, white or non-white race, procedure, and diagnosis were constructed to determine associations between interpreter use, LOS, and discharge disposition. Results: Forty-one patients were included in each cohort, exceeding the minimum number required per an a priori power analysis. Mean hospital LOS was longer in the interpreter cohort than in the non-interpreter cohort (2.8 ± 2.4 vs 1.8 ± 1.0 days, respectively). Multivariate linear regression demonstrated interpreter use was the strongest predictor of LOS, with the effect estimate indicating an additional 0.88-day LOS per patient. A greater proportion of patients from the interpreter cohort were discharged to an acute/subacute rehabilitation facility than patients from the non-interpreter cohort (n = 8 [19.5%] vs n = 2 [4.9%], respectively). Patients from the interpreter cohort were 454% more likely to be discharged to acute/subacute rehabilitation facilities. Conclusions: Our retrospective analysis of patients undergoing TSA suggests that the need for interpreter services may be associated with increased LOS and discharge to a facility. More rigorous study is needed to identify the factors that influence these outcomes and to avoid disparities in hospital stay and discharge.

Perioperative risk stratification tools for shoulder arthroplasty: a systematic review

BACKGROUND

Risk stratification tools are being increasingly utilized to guide patient selection for outpatient shoulder arthroplasty. The purpose of this study was to identify the existing calculators used to predict discharge disposition, postoperative complications, hospital readmissions, and patient candidacy for outpatient shoulder arthroplasty and to compare the specific components used to generate their prediction models.

METHODS

This review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis protocol. PubMed, Cochrane Library, Scopus, and OVID Medline were searched for studies that developed calculators used to determine patient candidacy for outpatient surgery or predict discharge disposition, the risk of postoperative complications, and hospital readmissions after anatomic or reverse total shoulder arthroplasty (TSA). Reviews, case reports, letters to the editor, and studies including hemiarthroplasty cases were excluded. Data extracted included authors, year of publication, study design, patient population, sample size, input variables, comorbidities, method of validation, and intended purpose. The pros and cons of each calculator as reported by the respective authors were evaluated.

RESULTS

Eleven publications met inclusion criteria. Three tools assessed patient candidacy for outpatient TSA, 3 tools evaluated the risk of 30- or 90-day hospital readmission and postoperative complications, and 5 tools predicted discharge destination. Four calculators validated previously constructed comorbidity indices used as risk predictors after shoulder arthroplasty, including the Charlson Comorbidity Index, Elixhauser Comorbidity Index, modified Frailty Index, and the Outpatient Arthroplasty Risk Assessment, while 7 developed newcalculators. Nine studies utilized multiple logistic regression to develop their calculators, while 1 study developed their algorithm based on previous literature and 1 used univariate analysis. Five tools were built using data from a single institution, 2 using data pooled from 2 institutions, and 4 from large national databases. All studies used preoperative data points in their algorithms with one tool additionally using intraoperative data points. The number of inputs ranged from 5 to 57 items. Four calculators assessed psychological comorbidities, 3 included inputs for substance use, and 1 calculator accounted for race.

CONCLUSION

The variation in perioperative risk calculators after TSA highlights the need for standardization and external validation of the existing tools. As the use of outpatient shoulder arthroplasty increases, these calculators may become outdated or require revision. Incorporation of socioeconomic and psychological measures into these calculators should be investigated.

Survivorship of Anatomic Total Shoulder Arthroplasty

Anatomic total shoulder arthroplasty provides pain relief and improved quality of life for patients suffering from glenohumeral arthritis. The 10-year survival rate for these implants has been most recently reported at 96%. As the number of shoulder arthroplasties per year increases, it is important to evaluate factors associated with failure. Patient-specific variables such as age, sex, medical comorbidities, a history of previous shoulder surgery, and rotator cuff integrity can influence implant survival. Both surgeon and hospital volume have been shown to affect perioperative outcomes. Implant design and glenoid pathoanatomy are important structural considerations because both have a causal relationship with survivorship. Modifiable factors, such as smoking, body mass index, and alcohol or opioid consumption, should be addressed preoperatively when possible. Modifiable factors that pertain to surgery are equally as important; it is the responsibility of the surgeon to be aware of the reported outcomes for varying implants and technique-related pearls and pitfalls. For those perioperative factors that are nonmodifiable, it is prudent to counsel patients accordingly because these individuals may be more likely to require an eventual revision procedure.

Declining trends in Medicare physician reimbursements for shoulder surgery from 2002 to 2018

BACKGROUND

As the current health care system evolves toward cost-containment and value-based approaches, evaluating trends in physician reimbursements will be critical for assessing and ensuring the financial stability of shoulder surgery as a subspecialty.

METHODS

The Medicare Physician Fee Schedule Look-up Tool was used to retrieve average reimbursement rates for 39 shoulder surgical procedures (arthroscopy with or without repair, arthroplasty, acromioclavicular or clavicular open reduction-internal fixation, fixation for proximal humeral fracture and/or shoulder dislocation, open rotator cuff repair or tendon release and/or repair, and open shoulder stabilization) from 2002 to 2018. All reimbursement data were adjusted for inflation to 2018 dollars.

RESULTS

After adjusting for inflation to 2018 dollars, average reimbursement for all included procedures decreased by 26.9% from 2002 to 2018. After stratifying the analysis by 3 distinct time groups, we observed that reimbursement decreases were the most significant prior to 2010. However, reimbursement rates still declined by an average of 2.9% from 2010 to 2014 and 7.2% from 2014 to 2018. Arthroscopic rotator cuff repair, capsulorrhaphy, and biceps tenodesis experienced smaller declines in reimbursement than their open-surgery counterparts.

CONCLUSION

Medicare physician reimbursements for shoulder surgical procedures have decreased over time. Health care policy makers need to understand the impact of decreasing reimbursements to develop agreeable financial policies that will not only ensure provider satisfaction but also maintain access to care for patients.

Trends in open shoulder surgery among early career orthopedic surgeons: who is doing what?

BACKGROUND

The incidence of various open shoulder procedures has changed over time. In addition, various fellowships provide overlapping training in open shoulder surgery. There is a lack of information regarding the relationship between surgeon training and open shoulder procedure type and incidence in early career orthopedic surgeons.

METHODS

The American Board of Orthopaedic Surgery Part-II database was queried from 2002 to 2016 for reported open shoulder procedures. The procedures were categorized as follows: arthroplasty, revision arthroplasty, open instability, trauma, and open rotator cuff. We evaluated procedure trends as well as their relationship to surgeon fellowship categorized by Sports, Shoulder/Elbow, Hand, Trauma, and "Other" fellowship as well as no fellowship training. We additionally evaluated complication data as it related to procedure, fellowship category, and volume.

RESULTS

Over the 2002-2016 study period, there were increasing cases of arthroplasty, revision arthroplasty, and trauma (P < .001). There were decreasing cases in open instability and open rotator cuff (P < .001). Those with Sports training reported the largest overall share of open shoulder cases. Those with Shoulder/Elbow training reported an increasing overall share of arthroplasty cases and higher per candidate case numbers. The percentage of early career orthopedic surgeons reporting 5 or more arthroplasty cases was highest among Shoulder/Elbow candidates (P < .001). Across all procedures, those without fellowship training were least likely to report a complication (odds ratio [OR], 0.76; 95% confidence interval, 0.67-0.86; P < .001). Shoulder/Elbow candidates were least likely to report an arthroplasty complication (OR, 0.84, P = .03) as was any surgeon reporting 5 or more arthroplasty cases (OR, 0.81; 95% confidence interval, 0.70-0.94; P = .006).

CONCLUSION

The type and incidence of open shoulder surgery procedures continues to change. Among early career surgeons, those with more specific shoulder training are now performing the majority of arthroplasty-related procedures, and early career volume inversely correlates with complications.

Defining the Volume-Outcome Relationship in Reverse Shoulder Arthroplasty: A Nationwide Analysis

BACKGROUND

As the utilization of reverse total shoulder arthroplasty (RSA) grows, it is increasingly important to examine the relationship between hospital volume and RSA outcomes. We hypothesized that hospitals that perform a higher volume of RSAs would have improved outcomes. We also performed stratum-specific likelihood ratio (SSLR) analysis with the aim of delineating concrete definitions of hospital volume for RSA.

METHODS

The Nationwide Readmissions Database was queried for patients who had undergone elective RSA from 2011 to 2015. Annual hospital volume and 90-day outcome data were collected, including readmission, revision, complications, hospital length of stay (LOS), supramedian cost, and discharge disposition. SSLR analysis was performed to determine hospital volume cutoffs associated with increased risks for adverse events. Cutoffs generated through SSLR analysis were confirmed via binomial logistic regression.

RESULTS

The proportion of patients receiving care at high-volume centers increased from 2011 to 2015. SSLR analysis produced hospital volume cutoffs for each outcome, with higher-volume centers showing improved outcomes. The volume cutoffs associated with the best rates of 90-day outcomes ranged from 54 to 70 RSAs/year, whereas cost and resource utilization cutoffs were higher, with the best outcomes in hospitals performing >100 RSAs/year. SSLR analysis of 90-day readmission produced 3 hospital volume categories (1 to 16, 17 to 69, and ≥70 RSAs/year), each significantly different from each other. These were similar to the strata for 90-day revision (1 to 16, 17 to 53, and ≥54 RSAs/year) and 90-day complications (1 to 9, 10 to 68, and ≥69 RSAs/year). SSLR analysis produced 6 hospital volume categories for cost of care over the median value (1 to 5, 6 to 25, 26 to 47, 48 to 71, 72 to 105, and ≥106 RSAs/year), 5 categories for an extended LOS (1 to 10, 11 to 25, 26 to 59, 60 to 105, and ≥106 RSAs/year), and 4 categories for non-home discharge (1 to 31, 32 to 71, 72 to 105, and ≥106 RSAs/year).

CONCLUSIONS

We have defined hospital surgical volumes that maximize outcomes after RSA, likely related to surgical experience, ancillary staff familiarity, and protocolized pathways. This information may be used in future policy decisions to consolidate complex procedures, such as RSA, at high-volume destinations, or to encourage lower-volume institutions to strategize an approach to function as a higher-volume center.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparing the Use of Axillary Radiographs and Axial Computed Tomography Scans to Predict Concentric Glenoid Wear

Background:

Axillary radiographs traditionally have been considered sufficient to identify concentric glenoid wear in osteoarthritic shoulders; however, with variable glenoid wear patterns, assessment with use of computed tomography (CT) has been recommended. The purpose of the present study was to compare the use of axillary radiographs and mid-glenoid axial CT scans to identify glenoid wear.

Methods:

Preoperative axillary radiographs and mid-glenoid axial CT scans for 330 patients who underwent anatomic total shoulder arthroplasty were reviewed. Five independent examiners with differing levels of experience characterized the glenoid morphology as either concentric or eccentric. The morphologies determined with use of axillary radiographs and CT scans were assessed for correlation, and both intraobserver and interobserver consistency were calculated.

Results:

Concentric wear identified with use of radiographs was confirmed with use of CT scans in an average of 61% of cases (range, 53% to 76%). Intraobserver consistency averaged 75% for radiographs and 73% for CT scans. There was significant interobserver consistency, as higher levels of training corresponded with greater consistency between imaging analyses (p < 0.001). The most senior observer identified the highest proportion of concentric wear on radiographs (p < 0.001), showed the greatest consistency between attempts when using CT (p < 0.001), and had the greatest agreement of radiographs and CT evaluating glenoid morphology (p < 0.001).

Conclusions:

For the experienced shoulder surgeon, concentric glenoid wear identified on axillary radiographs will appear concentric on 2-dimensional CT in approximately 75% of cases. Obtaining a CT scan to confirm glenoid wear patterns most greatly benefits less-experienced surgeons. Across all levels of experience, axillary radiographs and single-slice, mid-glenoid CT scans appear insufficient for consistently predicting wear patterns.

Level of Evidence:

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.