Variations in 1-year Trajectories of Levels of Pain and Capability After Shoulder Arthroplasty Are Associated With Baseline Mental Health.

BACKGROUND: There is variability in the trajectories of pain intensity and magnitude of incapability after shoulder arthroplasty. A better understanding of the degree to which variation in recovery trajectories relates to aspects of mental health can inform the development of comprehensive biopsychosocial care strategies. QUESTIONS/PURPOSES: (1) Do pain intensities at baseline and the trajectories during recovery differ between groups when stratified by mental health composite summary score, arthroplasty type, and revision surgery? (2) Do magnitudes of capability at baseline and the trajectories during recovery differ between these groups? METHODS: We used a registry of 755 patients who underwent shoulder arthroplasty by a single surgeon at a specialized urban orthopaedic hospital that recorded the mental component summary (MCS) score of the Veterans RAND 12, a measure of shoulder-specific comfort and capability (American Shoulder and Elbow Surgeons [ASES] score, which ranges from 0 to 100 points, with a score of 0 indicating worse capability and pain and 100 indicating better capability and pain and a minimum clinically important difference of 6.4), and the VAS for pain intensity (range 0 [representing no pain] to 10 [representing the worst pain possible], with a minimum clinically important difference of 1.4) preoperatively, 2 weeks postoperatively, and 6 weeks, 3 months, 6 months, and 1 year after surgery. Forty-nine percent (368 of 755) of the patients were men, with a mean age of 68 ± 8 years, and 77% (585) were treated with reverse total shoulder arthroplasty (rTSA). Unconditional linear and quadratic growth models were generated to identify the general shape of recovery for both outcomes (linear versus quadratic). We then constructed conditional growth models and curves for pain intensity and the magnitude of capability showing mean baseline scores and the rates of recovery that determine the trajectory, accounting for mental health (MCS) quartiles, primary or revision arthroplasty, and TSA or reverse TSA in separate models. Because pain intensity and capability showed quadratic trends, we created trajectories using the square of time. RESULTS: Patients in the worst two MCS quartiles had greater pain intensity at baseline than patients in the best quartile (difference in baseline for bottom quartile: 0.93 [95% CI 0.72 to 1.1]; p < 0.01; difference in baseline for next-worst quartile: 0.36 [95% CI 0.16 to 0.57]; p < 0.01). The rates of change in recovery from pain intensity were not different among groups (p > 0.10). Patients with revision surgery had greater baseline pain (difference: 1.1 [95% CI 0.7 to 1.5]; p < 0.01) but no difference in rates of recovery (difference: 0.031 [95% CI 0.035 to 0.097]; p = 0.36). There were no differences in baseline pain intensity and rates of recovery between patients with reverse TSA and those with TSA (baseline pain difference: -0.20 [95% CI -0.38 to -0.03]; p = 0.18; difference in rate of recovery: -0.005 [95% CI -0.035 to 0.025]; p = 0.74). Patients in the worst two MCS quartiles had worse baseline capability than patients in the best quartile (difference in baseline for bottom quartile: -8.9 [95% CI -10 to -7.4]; p < 0.001; difference in baseline for the next-worst quartile: -4.9 [95% CI -6.4 to -3.4]; p < 0.01), with no differences in rates of recovery (p > 0.10). Patients with revision surgery had lower baseline capability (difference in baseline: -13 [95% CI -15 to -9.7]; p < 0.01), with a slower rate of recovery (difference in rate of recovery: -0.56 [95% CI -1.0 to -0.079]; p = 0.021). There were no differences in baseline capability or rates of recovery between TSA and reverse TSA. CONCLUSION: The observation that preoperative and 1-year comfort and capability are associated with mental health factors and with similar recovery trajectories reminds us that assessment and treatment of mental health is best considered an integral aspect of musculoskeletal care. Future studies can address how prioritization of mental health in musculoskeletal care strategies might reduce variation in the 1-year outcomes of discretionary surgeries such as shoulder arthroplasty. LEVEL OF EVIDENCE: Level III, therapeutic study.

Outcomes after reverse shoulder arthroplasty for the treatment of glenohumeral osteoarthritis in patients under and over 70 years of age: a propensity score-matched analysis.

INTRODUCTION: As reverse shoulder arthroplasty (RSA) continues to grow in popularity for the treatment of glenohumeral osteoarthritis (GHOA) with an intact rotator cuff, it becomes increasingly important to identify factors that influence postoperative outcome. Although recent studies have demonstrated excellent postoperative range of motion and patient-reported outcome scores following RSA for GHOA, there continues to be surgeon hesitation to adopt RSA as a viable treatment in the younger patient population due to greater functional demands. In this study, we sought to determine the effect of age on clinical outcomes following RSA for GHOA through a comparison of patients over and under the age of 70. METHODS: A retrospective review of prospectively collected data from an institutional registry was performed. Propensity score matching was utilized to match patients under the age of 70 (U-70) to those over 70 (O-70) in a 1:1 ratio based on sex, body mass index (BMI), preoperative ASES score, preoperative active forward elevation (FE), Walch classification, and American Society of Anesthesiologists comorbidity score. Clinical outcomes obtained preoperatively and at a minimum of 2 years postoperatively consisted of Visual Analog Scale (VAS) for pain, Single Assessment Numeric Evaluation (SANE) score, and American Shoulder and Elbow Surgeons (ASES) score, as well as active (FE), internal rotation, and external rotation. Descriptive statistics and univariate analysis were performed to compare cohorts. RESULTS: After matching, each cohort consisted of 66 patients with similar mean follow-up periods (U-70, 28.1 ± 7.5 months vs. O-70, 27.4 ± 7.5 months; P = .887). Mean age of the U-70 cohort was 66.2 ± 3.3 while the O-70 cohort had a mean age of 75.3 ± 3.8. Both groups demonstrated significant improvement in VAS, SANE, and ASES scores, as well as active range of motion in all planes. The only significant difference between cohorts was greater postoperative FE in younger patients (143 ± 16° vs. 136 ± 15°; P = .017), though the baseline-to-postoperative improvement in FE was similar between cohorts (50 ± 29° vs. 43 ± 29°, P = .174). CONCLUSION: RSA is a successful surgical treatment for GHOA regardless of age. Aside from greater postoperative FE in younger patients, there were no other differences in clinical outcomes between younger and older patients in this retrospective analysis, which compared patients who were matched by sex, BMI, and Walch classification, among other factors. Based on our results, 70 years of age should not be used as a threshold in preoperative counseling when determining whether a patient with GHOA with an intact rotator cuff is indicated for reverse shoulder arthroplasty.

Clinically significant outcome thresholds and rates of achievement by shoulder arthroplasty type and preoperative diagnosis.

BACKGROUND: Clinically significant outcome (CSO) benchmarks have been previously established for shoulder arthroplasty by assimilating preoperative diagnoses and arthroplasty types. The purpose of this study was to establish unique CSO thresholds and compare the time-to-achievement of these for reverse shoulder arthroplasty (RSA) for osteoarthritis (GHOA), RSA for rotator cuff arthropathy (RCA), and total shoulder arthroplasty (TSA) for GHOA. MATERIALS AND METHODS: Consecutive patients who underwent elective RSA for GHOA, TSA for GHOA, or RSA for RCA between February 2015 and May 2020, with 2-year minimum follow-up, were retrospectively identified from a prospectively maintained single surgeon registry. The American Shoulder and Elbow Surgeons (ASES) score was administered preoperatively and postoperatively at 2-week, 6-week, 3-month, 6-month, 1-year, and 2-year timepoints. Satisfaction and subjective overall improvement anchor questionnaires were administered at the time of final follow-up. Distribution-based methods were used to calculate the Minimal Clinically Important Difference (MCID), and anchor-based methods were used to calculate the Substantial Clinical Benefit (SCB) and the Patient Acceptable Symptom State (PASS) for each patient group. Median time to achievement, individual incidence of achievement at each time point, and cumulative incidence of achievement calculated using Kaplan-Meier survival curve analysis with interval censoring were compared between groups for each CSO. Cox-regression analyses were also performed to determine which patient factors were significantly associated with early or delayed achievement of CSOs. RESULTS: There were 471 patients eligible for study analysis: 276 RSA for GHOA, 107 TSA for GHOA, and 88 RSA for RCA. The calculated MCID, SCB, and PASS scores differed for each group. There were no significant differences in median time to achievement of any CSO between groups. Log-rank testing revealed that cumulative achievements significantly differed between groups for MCID (P = .014) but not for SCB (P = .053) or PASS (P = .620). On cox regression analysis, TSA patients had earlier achievement of SCB, whereas TSA and RSA for GHOA patients had earlier achievement of MCID. At 2-years, a significantly higher percentage of RSA for GHOA patients achieved MCID and SCB compared to RSA for RCA (MCID:100%, 95.5%, P = .003, SCB:94.6%, 86.4%, P = .036). CONCLUSION: Calculated CSO thresholds differ according to preoperative diagnosis and shoulder arthroplasty type. Patients undergoing TSA and RSA for GHOA achieve CSOs earlier than RSA for RCA patients, and a significantly higher percentage of RSA for GHOA patients achieve CSOs by 2 years compared to RSA for RCA patients.

Predictors of poor and excellent outcomes following reverse shoulder arthroplasty for glenohumeral osteoarthritis with an intact rotator cuff.

BACKGROUND: As the indications for reverse total shoulder arthroplasty (RSA) continue to evolve, it has been more commonly utilized for the treatment of glenohumeral osteoarthritis with an intact rotator cuff (GHOA). Given the increased use of RSA for GHOA, it is important to identify factors influential of clinical outcomes. In this study, we sought to identify variables predictive of clinical outcomes following RSA for GHOA. METHODS: Patients undergoing primary RSA for GHOA between 2015 and 2020 were retrospectively identified through a prospectively maintained, single surgeon registry. Eligible patients had complete patient-reported outcome measures and range of motion measurements with a minimum 2-year follow-up. Univariate analysis was utilized to compare characteristics and outcome measures of patients with poor and excellent outcomes, which was defined as postoperative American Shoulder and Elbow Surgeons (ASES) scores in the bottom and top quartiles, respectively. Multivariate linear regression was performed to determine factors independently predictive of postoperative ASES score. RESULTS: A total of 230 patients were included with a mean follow-up of 33.4 months (SD 13.2). The mean age of the study population was 71.9 (SD 6.1). Two hundred twenty-four patients (97.4%) surpassed the minimal clinically important difference and 209 patients (90.1%) achieved substantial clinical benefit for ASES score. Preoperative factors differing between the poor and excellent outcome groups were sex (male: poor 37.9%, excellent 58.6%; P = .041), opioid use (poor 24.1%, excellent 5.2%; P = .009), ASES score (poor 32.9, excellent 41.0; P = .011), and forward elevation (poor 92°, excellent 101°; P = .030). Linear regression demonstrated that Walch B3 glenoids (ß 7.08; P = .010) and higher preoperative ASES scores (ß 0.14; P = .025) were predictors of higher postoperative ASES score, while postoperative complications (ß -18.66; P < .001) and preoperative opioid use (ß -11.88; P < .001) were predictive of lower postoperative ASES scores. CONCLUSION: Over 90% of patients who underwent RSA for GHOA with an intact rotator cuff experienced substantial clinical benefit. An unsurprising handful of factors were associated with postoperative clinical outcomes; higher preoperative ASES scores were slightly associated with higher postoperative ASES, whereas preoperative opioid use and postoperative complications were associated with lower postoperative ASES. Additionally, Walch glenoid type B3 was associated with higher postoperative ASES, indicating that patients with posterior glenoid defects are not predisposed to poor clinical outcomes following RSA. These results serve as a resource to improve preoperative patient counseling and manage postoperative expectations.

Effect of vitamin E-enhanced highly cross-linked polyethylene on wear rate and particle debris in anatomic total shoulder arthroplasty: a biomechanical comparison to ultrahigh-molecular-weight polyethylene.

BACKGROUND: Particle-induced osteolysis resulting from polyethylene wear remains a source of implant failure in anatomic total shoulder designs. Modern polyethylene components are irradiated in an oxygen-free environment to induce cross-linking, but reducing the resulting free radicals with melting or heat annealing can compromise the component's mechanical properties. Vitamin E has been introduced as an adjuvant to thermal treatments. Anatomic shoulder arthroplasty models with a ceramic head component have demonstrated that vitamin E-enhanced polyethylene show improved wear compared with highly cross-linked polyethylene (HXLPE). This study aimed to assess the biomechanical wear properties and particle size characteristics of a novel vitamin E-enhanced highly cross-linked polyethylene (VEXPE) glenoid compared to a conventional ultrahigh-molecular-weight polyethylene (UHMWPE) glenoid against a cobalt chromium molybdenum (CoCrMo) head component. METHODS: Biomechanical wear testing was performed to compare the VEXPE glenoid to UHMWPE glenoid with regard to pristine polyethylene wear and abrasive endurance against a polished CoCrMo alloy humeral head in an anatomic shoulder wear-simulation model. Cumulative mass loss (milligrams) was recorded, and wear rate calculated (milligrams per megacycle [Mc]). Under pristine wear conditions, particle analysis was performed, and functional biologic activity (FBA) was calculated to estimate particle debris osteolytic potential. In addition, 95% confidence intervals for all testing conditions were calculated. RESULTS: The average pristine wear rate was statistically significantly lower for the VEXPE glenoid compared with the HXLPE glenoid (0.81 ± 0.64 mg/Mc vs. 7.00 ± 0.45 mg/Mc) (P < .05). Under abrasive wear conditions, the VEXPE glenoid had a statistically significant lower average wear rate compared with the UHMWPE glenoid comparator device (18.93 ± 5.80 mg/Mc vs. 40.47 ± 2.63 mg/Mc) (P < .05). The VEXPE glenoid demonstrated a statistically significant improvement in FBA compared with the HXLPE glenoid (0.21 ± 0.21 vs. 1.54 ± 0.49 (P < .05). CONCLUSIONS: A new anatomic glenoid component with VEXPE demonstrated significantly improved pristine and abrasive wear properties with lower osteolytic particle debris potential compared with a conventional UHMWPE glenoid component. Vitamin E-enhanced polyethylene shows early promise in shoulder arthroplasty components. Long-term clinical and radiographic investigation needs to be performed to verify if these biomechanical wear properties translate to diminished long-term wear, osteolysis, and loosening.

Modular baseplate augmentation: a simple and effective method for addressing eccentric glenoid wear.

BACKGROUND: Augmented baseplates can be effective at addressing eccentric glenoid wear in reverse total shoulder arthroplasty. However, these implants often come in a limited number of predetermined shapes that require additional reaming to ensure adequate glenoid seating. This typically involves complex instrumentation and can have a negative impact on implant stability. Modular baseplate augmentation based on intraoperative measurements may allow for more precise defect filling while preserving glenoid bone. The purpose of this investigation was to assess the stability of a novel ringed baseplate with modular augmentation in comparison with nonaugmented standard and ringed baseplate designs. METHODS: In this biomechanical study, baseplate micromotion was tested for 3 constructs according to the American Society for Testing and Materials guidelines. The constructs included a nonaugmented curved baseplate, a nonaugmented ringed baseplate, and a ringed baseplate with an 8-mm locking modular augmentation peg. The nonaugmented constructs were mounted flush onto polyurethane foam blocks, whereas the augmented baseplate was mounted on a polyurethane block with a simulated defect. Baseplate displacement was measured before and after 100,000 cycles of cyclic loading. RESULTS: Before cyclic loading, the nonaugmented and augmented ringed baseplates both demonstrated significantly less micromotion than the nonaugmented curved baseplate design (81.1 µm vs. 97.2 µm vs. 152.7 µm; P = .009). After cyclic loading, both ringed constructs continued to have significantly less micromotion than the curved design (105.5 µm vs. 103.2 µm vs. 136.6 µm; P < .001). The micromotion for both ringed constructs remained below the minimum threshold required for bony ingrowth (150 µm) at all time points. CONCLUSIONS: In the setting of a simulated glenoid defect, locked modular augmentation of a ringed baseplate does not result in increased baseplate micromotion when compared with full contact nonaugmented baseplates. This design offers a simple method for tailored baseplate augmentation that can match specific variations in glenoid anatomy, limiting the need for excessive reaming and ultimately optimizing the environment for long-term implant stability.

Higher Surgeon Volume is Associated With a Lower Rate of Subsequent Revision Procedures After Total Shoulder Arthroplasty: A National Analysis.

BACKGROUND: Studies assessing the relationship between surgeon volume and outcomes have shown mixed results, depending on the specific procedure analyzed. This volume relationship has not been well studied in patients undergoing total shoulder arthroplasty (TSA), but it should be, because this procedure is common, expensive, and potentially morbid. QUESTIONS/PURPOSES: We performed this study to assess the association between increasing surgeon volume and decreasing rate of revision at 2 years for (1) anatomic TSA (aTSA) and (2) reverse TSA (rTSA) in the United States. METHODS: In this retrospective study, we used Centers for Medicare and Medicaid Services (CMS) fee-for-service inpatient and outpatient data from 2015 to 2021 to study the association between annual surgeon aTSA and rTSA volume and 2-year revision shoulder procedures after the initial surgery. The CMS database was chosen for this study because it is a national sample and can be used to follow patients over time. We included patients with Diagnosis-related Group code 483 and Current Procedural Terminology code 23472 for TSA (these codes include both aTSA and rTSA). We used International Classification of Diseases, Tenth Revision, procedural codes. Patients who underwent shoulder arthroplasty for fracture (10% [17,524 of 173,242]) were excluded. We studied the variables associated with the subsequent procedure rate through a generalized linear model, controlling for confounders such as patient age, comorbidity risk score, surgeon and hospital volume, surgeon graduation year, hospital size and teaching status, assuming a binomial distribution with the dependent variable being whether an episode had at least one subsequent procedure within 2 years. The regression was fitted with standard errors clustered at the hospital level, combining all TSAs and within the aTSA and rTSA groups, respectively. Hospital and surgeon yearly volumes were calculated by including all TSAs, primary procedure and subsequent, during the study period. Other hospital-level and surgeon-level characteristics were obtained through public files from the CMS. The CMS Hierarchical Condition Category risk score was controlled because it is a measure reflecting the expected future health costs for each patient based on the patient's demographics and chronic illnesses. We then converted regression coefficients to the percentage change in the odds of having a subsequent procedure. RESULTS: After controlling for confounding variables including patient age, comorbidity risk score, surgeon and hospital volume, surgeon graduation year, and hospital size and teaching status, we found that an annual surgeon volume of ≥ 10 aTSAs was associated with a 27% decreased odds of revision within 2 years (95% confidence interval 13% to 39%; p < 0.001), while surgeon volume of ≥ 29 aTSAs was associated with a 33% decreased odds of revision within 2 years (95% CI 18% to 45%; p < 0.001) compared with a volume of fewer than four aTSAs per year. Annual surgeon volume of ≥ 29 rTSAs was associated with a 26% decreased odds of revision within 2 years (95% CI 9% to 39%; p < 0.001). CONCLUSION: Surgeons should consider modalities such as virtual planning software, templating, or enhanced surgeon training to aid lower-volume surgeons who perform aTSA and rTSA. More research is needed to assess the value of these modalities and their relationship with the rates of subsequent revision. LEVEL OF EVIDENCE: Level III, therapeutic study.

Anatomic and reverse shoulder arthroplasty for management of type B2 and B3 glenoids: a matched-cohort analysis.

BACKGROUND: Severe glenohumeral osteoarthritis (GHOA) with posterior glenoid erosion remains challenging to address for shoulder surgeons. Whereas anatomic total shoulder arthroplasty (TSA) has historically been the treatment of choice, reverse shoulder arthroplasty (RSA) offers an alternative option. Limited evidence exists directly comparing these 2 treatments in a similar patient population. The purpose of this study was to compare the clinical outcomes of patients with GHOA and Walch type B2 and B3 glenoid morphologies treated with TSA vs. RSA. METHODS: We performed a multicenter retrospective cohort study of patients with GHOA who were treated with primary shoulder arthroplasty and had a minimum follow-up period of 2 years. Preoperative computed tomography was used to determine type B2 and B3 glenoid morphology as described by the modified Walch classification. Three-dimensional perioperative planning software was used to characterize glenoid retroversion and humeral subluxation. Patients were categorized based on type of arthroplasty (TSA or RSA) and were matched 1:1 by sex, Walch classification, and age. Patient-reported outcome measures, active range of motion, presence and severity of glenoid loosening, and complications were compared. The percentage of patients who reached previously established clinically significant thresholds of the minimal clinically important difference and substantial clinical benefit for the American Shoulder and Elbow Surgeons score was also comparatively assessed. RESULTS: In total, 202 patients (101 per group) with GHOA and type B2 or B3 glenoids were included in the 1:1 matched analysis. The mean length of follow-up (± standard deviation) was 39 ± 18.7 months. The cohorts were well matched, with no differences in sex, age, American Society of Anesthesiologists score, body mass index, preoperative glenoid morphology (Walch classification), glenoid retroversion, or posterior subluxation (P > .05). RSA was associated with a lower postoperative visual analog scale pain score (0.5 in RSA group vs. 1.2 in TSA group, P = .036); however, no other no other significant differences in patient-reported significant differences in patient-reported outcome measures were found. Most patients in both groups (95.0% in TSA group vs. 98.0% in RSA group, P = .436) reached the minimal clinically important difference, and 82% of TSA patients and 90% of RSA patients reached the substantial clinical benefit value (P = .292). No significant differences in the overall complication rate (P = .781) and active range of motion were found, with the exception of internal rotation (scored on a numeric scale) being worse in the RSA group (2.7 preoperatively and 5.2 postoperatively in RSA group vs. 3.9 and 6.5, respectively, in TSA group; P < .001). Baseplate loosening occurred in 2 RSA cases, and 29 TSA cases had glenoid radiolucencies (P < .001), with 3 grossly loose glenoid components. CONCLUSION: Primary RSA results in short-term outcomes largely comparable to those of TSA in patients with Walch type B2 or B3 glenoid morphology. Both TSA and RSA provide substantial clinical benefit to patients with significant posterior glenoid wear.

Indication matters: effect of indication on clinical outcome following reverse total shoulder arthroplasty-a multicenter study.

BACKGROUND: As the utilization and success of reverse total shoulder arthroplasty (RTSA) have continued to grow, so have its surgical indications. Despite the adoption of RTSA for the treatment of glenohumeral osteoarthritis (GHOA) with an intact rotator cuff and irreparable massive rotator cuff tears (MCTs) without arthritis, the literature remains sparse regarding the differential outcomes after RTSA among these varying indications. Thus, the purpose of this study was to examine the postoperative clinical outcomes of RTSA based on indication. METHODS: A retrospective review of 2 large institutional databases was performed to identify all patients who underwent RTSA between 2015 and 2019 with minimum 2-year follow-up. Patients were stratified by indication into 3 cohorts: GHOA, rotator cuff tear arthropathy (CTA), and MCT. Baseline demographic characteristics were collected to determine differences between the 3 cohorts. Clinical outcomes were measured preoperatively and postoperatively, including active range of motion, American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation score, and visual analog scale pain score. Multivariate linear regression was performed to determine the factors independently predictive of the postoperative ASES score. RESULTS: A total of 625 patients (383 with GHOA, 164 with CTA, and 78 with MCTs) with a mean follow-up period of 33.4 months were included in the analysis. Patients with GHOA had superior ASES scores (85.6 ± 15.7 vs. 76.6 ± 20.8 in CTA cohort [P < .001] and 75.9 ± 19.9 in MCT cohort [P < .001]), Single Assessment Numeric Evaluation scores (86 ± 20.9 vs. 76.7 ± 24.1 in CTA cohort [P < .001] and 74.2 ± 25.3 in MCT cohort [P < .001]), and visual analog scale pain scores (median [interquartile range], 0.0 [0.0-1.0] vs. 0.0 [0.0-2.0] in CTA cohort [P < .001] and 0.0 [0.0-2.0] in MCT cohort [P < .001]) postoperatively. Postoperative active forward elevation (P < .001) and improvement in active external rotation (P < .001) were greatest in the GHOA cohort compared with other indications. Multivariate linear regression demonstrated that the factors independently associated with the postoperative ASES score included a diagnosis of GHOA (ß coefficient, 7.557 [P < .001]), preoperative ASES score (ß coefficient, 0.114 [P = .009]), female sex (ß coefficient, -4.476 [P = .002]), history of surgery (ß coefficient, -3.957 [P = .018]), and postoperative complication (ß coefficient, -13.550 [P < .001]). CONCLUSION: RTSA for the treatment of GHOA generally has superior patient-reported and functional outcomes when compared with CTA and MCTs without arthritis. Long-term follow-up is needed to identify the lasting implications of such outcome differences.

Substantial Inconsistency and Variability Exists Among Minimum Clinically Important Differences for Shoulder Arthroplasty Outcomes: A Systematic Review.

BACKGROUND: As the value of patient-reported outcomes becomes increasingly recognized, minimum clinically important difference (MCID) thresholds have seen greater use in shoulder arthroplasty. However, MCIDs are unique to certain populations, and variation in the modes of calculation in this field may be of concern. With the growing utilization of MCIDs within the field and value-based care models, a detailed appraisal of the appropriateness of MCID use in the literature is necessary and has not been systematically reviewed. QUESTIONS/PURPOSES: We performed a systematic review of MCID quantification in existing studies on shoulder arthroplasty to answer the following questions: (1) What is the range of values reported for the MCID in commonly used shoulder arthroplasty patient-reported outcome measures (PROMs)? (2) What percentage of studies use previously existing MCIDs versus calculating a new MCID? (3) What techniques for calculating the MCID were used in studies where a new MCID was calculated? METHODS: The Embase, PubMed, and Ovid/MEDLINE databases were queried from December 2008 through December 2020 for total shoulder arthroplasty and reverse total shoulder arthroplasty articles reporting an MCID value for various PROMs. Two reviewers (DAK, MAM) independently screened articles for eligibility, specifically identifying articles that reported MCID values for PROMs after shoulder arthroplasty, and extracted data for analysis. Each study was classified into two categories: those referencing a previously defined MCID and those using a newly calculated MCID. Methods for determining the MCID for each study and the variability of reported MCIDs for each PROM were recorded. The number of patients, age, gender, BMI, length of follow-up, surgical indications, and surgical type were extracted for each article. Forty-three articles (16,408 patients) with a mean (range) follow-up of 20 months (0.75 to 68) met the inclusion criteria. The median (range) BMI of patients was 29.3 kg/m2 (28.0 to 32.2 kg/m2), and the median (range) age was 68 years (53 to 84). There were 17 unique PROMs with MCID values. Of the 112 MCIDs reported, the most common PROMs with MCIDs were the American Shoulder and Elbow Surgeons (ASES) (23% [26 of 112]), the Simple Shoulder Test (SST) (17% [19 of 112]), and the Constant (15% [17 of 112]). RESULTS: The ranges of MCID values for each PROM varied widely (ASES: 6.3 to 29.5; SST: 1.4 to 4.0; Constant: -0.3 to 12.8). Fifty-six percent (24 of 43) of studies used previously established MCIDs, with 46% (11 of 24) citing one study. Forty-four percent (19 of 43) of studies established new MCIDs, and the most common technique was anchor-based (37% [7 of 19]), followed by distribution (21% [4 of 19]). CONCLUSION: There is substantial inconsistency and variability in the quantification and reporting of MCID values in shoulder arthroplasty studies. Many shoulder arthroplasty studies apply previously published MCID values with variable ranges of follow-up rather than calculating population-specific thresholds. The use of previously calculated MCIDs may be acceptable in specific situations; however, investigators should select an anchor-based MCID calculated from a patient population as similar as possible to their own. This practice is preferable to the use of distribution-approach MCID methods. Alternatively, authors may consider using substantial clinical benefit or patient-acceptable symptom state to assess outcomes after shoulder arthroplasty. CLINICAL RELEVANCE: Although MCIDs may provide a useful effect-size based alternative to the traditional p value, care must be taken to use an MCID that is appropriate for the particular patient population being studied.

Baseplate retroversion does not affect postoperative outcomes after reverse shoulder arthroplasty.

BACKGROUND: There is concern that excessive glenoid component retroversion leads to altered biomechanics and baseplate failure in reverse shoulder arthroplasty (RSA). However, much of this has been rooted in the total shoulder arthroplasty experience. In the current literature, it is not well defined whether glenoid baseplate positioning in reverse arthroplasty affects functional outcomes. Our practice has been to preserve glenoid bone stock without aiming for a certain degree of retroversion. We aimed to evaluate the correlation between pre- and postoperative retroversion in a cohort of RSAs and determine the effect of glenoid retroversion on functional outcomes, range of motion, and postoperative complications. METHODS: A retrospective review of patients who had an RSA between 2017 and 2019 was performed. Preoperative computed tomography scans were used to assess preoperative retroversion, and axillary radiographs were used for postoperative retroversion. Outcome measures included American Shoulder and Elbow Surgeons score, visual analog scale for pain score, Single Assessment Numeric Evaluation score, range of motion, radiographic lucency, and complications. RESULTS: A total of 271 patients were eligible for the study. There was a 76.9% 2-year follow-up rate. In total 161 patients had postoperative retroversion ≤15° (group A), and 110 patients had retroversion >15° (group B). There were no significant differences in American Shoulder and Elbow Surgeons, visual analog scale, or Single Assessment Numeric Evaluation scores. There were also no significant differences in postoperative range of motion. There was 1 baseplate failure in each group, and there was 1 patient in group B with asymptomatic radiographic loosening (baseplate at risk). The mean change in pre- to postoperative retroversion was 1° and 4° in groups A and B, respectively. CONCLUSION: There was no significant difference in postoperative functional outcomes, range of motion, or complications between patients who had baseplate retroversion ≤15° vs. those who had retroversion >15°.

Predictors of poor and excellent outcomes after reverse total shoulder arthroplasty.

BACKGROUND: Favorable clinical and functional outcomes can be achieved with reverse total shoulder arthroplasty (RSA). Given the expanding utilization of RSA in the United States, understanding the factors that influence both excellent and poor outcomes is increasingly important. METHODS: A single-surgeon prospective registry was used to identify patients who underwent RSA from 2015 to 2018 with a minimum of 2 years' follow-up. An excellent postoperative clinical outcome was defined as a final American Shoulder and Elbow Surgeons (ASES) score in the top quartile of ASES scores. A poor outcome was defined as an ASES score in the bottom quartile. Logistic regression was used to determine preoperative characteristics associated with both excellent and poor outcomes. RESULTS: A total of 338 patients with a mean age of 71.5 years (standard deviation [SD], 6.4 years) met the inclusion and exclusion criteria. The average preoperative ASES score for the entire cohort was 35.3 (SD, 16.4), which improved to 82.4 (SD, 16.1) postoperatively (P < .001). Univariate analysis demonstrated that a diagnosis of primary osteoarthritis (OA), private insurance, and higher preoperative ASES scores were significantly associated with achieving excellent outcomes (P < .01 for all). Variables predictive of poor outcomes were workers' compensation status (P = .03), depression (P = .02), a preoperative diagnosis of rotator cuff tear arthropathy (P < .01), preoperative opioid use (P < .01), a higher number of allergies (P < .01), and prior ipsilateral shoulder surgery (P < .01). Multivariate regression analysis demonstrated that OA (odds ratio [OR], 5.6; 95% confidence interval [CI], 1.2-26.5; P = .03) and private insurance (OR, 2.7; 95% CI, 1.12-6.5; P = .02) correlated with excellent outcomes whereas a higher number of reported allergies (OR, 0.83; 95% CI, 0.71-0.97; P = .02), self-reported depression (OR, 0.39; 95% CI, 0.16-0.99; P =.04), a history of ipsilateral shoulder surgery (OR, 0.36; 95% CI, 0.15-0.87; P =.02), and preoperative opioid use (OR, 0.26; 95% CI, 0.09-0.76; P = .01) were predictive of poor outcomes. CONCLUSIONS: A preoperative diagnosis of primary OA is the strongest predictor of excellent clinical outcomes following RSA. Patients with an increasing number of reported allergies, self-reported depression, a history of ipsilateral shoulder surgery, and preoperative opioid use are significantly more likely to achieve poor outcomes after RSA. Given the increasing utilization of RSA, this information is important to appropriately counsel patients regarding postoperative expectations.

Primary reverse total shoulder arthroplasty performed for glenohumeral arthritis: does glenoid morphology matter?

BACKGROUND: Indications for reverse total shoulder arthroplasty (RTSA) have expanded to include primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Limited evidence exists on RTSA in patients with primary GHOA and no posterior glenoid wear (Walch A1, A2, and B1 morphologies). The purpose of this retrospective cohort study was to determine if glenoid morphology is associated with clinical outcomes in patients undergoing RTSA for primary GHOA. METHODS: A retrospective review of prospectively collected data was performed in patients undergoing primary RTSA for GHOA with a minimum of 2-year clinical follow-up. Preoperative computed tomography and magnetic resonance imaging were used to categorize glenoid morphology as described by the modified Walch classification. Pre- and postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Single Assessment Numeric Evaluation (SANE), visual analog scale (VAS) pain scores, and range of motion (ROM) measurements were compared across Walch glenoid subtypes. The percentage of patients that reached previously established clinically significant thresholds for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) was also comparatively assessed. Multivariable analysis was used to evaluate the association between glenoid morphology and postoperative ASES score while controlling for potentially confounding variables. RESULTS: Of the 247 consecutive patients, 197 were available at a minimum 2-year follow-up (80%). Significant improvements were seen in ASES, VAS pain, SANE, and ROM from baseline to final postoperative follow-up in the combined patient cohort (all P < .001). Most (98.0%) patients reached MCID, and 90.9% of patients reached SCB for ASES threshold. No significant differences were found among Walch subtypes in terms of preoperative to postoperative improvement in ASES (P = .39), SANE (P = .4), VAS pain (P = .49), forward elevation (P = .77), external rotation (P = .45), or internal rotation (P= 0.1). The only significant difference in postoperative outcomes between Walch glenoid subtypes was higher postoperative ASES scores among type B3 glenoids compared with type A1 glenoids (P = .03) on univariate analysis. However, no individual Walch glenoid subtype was associated with lower postoperative ASES scores on multivariable analysis (P > .05). CONCLUSION: Primary RTSA provides excellent short-term outcomes in patients with glenohumeral arthritis with intact rotator cuff, regardless of the degree of preoperative glenoid deformity. Surgeons can use these data to support the use of RTSA for glenohumeral arthritis in a more standardized way.

Functional somatic syndromes are associated with suboptimal outcomes and high cost after shoulder arthroplasty.

BACKGROUND: The presence of functional somatic syndromes (chronic physical symptoms with no identifiable organic cause) in patients undergoing elective joint arthroplasty may affect the recovery experience. We explored the prevalence of functional somatic syndromes among shoulder arthroplasty patients, as well as their association with postoperative outcomes and costs. METHODS: We identified 480 patients undergoing elective total shoulder arthroplasty (anatomic or reverse) between 2015 and 2018 in our institutional registry with minimum 2-year follow-up. Medical records were queried for the presence of 4 well-recognized functional somatic syndromes: fibromyalgia, irritable bowel syndrome, chronic headaches, and chronic low-back pain. Multivariable linear regression modeling was used to determine the independent association of these diagnoses with hospitalization time-driven activity-based costs and 2-year postoperative American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and pain scores. RESULTS: Nearly 1 in 5 patients (17%) reported at least 1 functional somatic syndrome. These patients were more likely to be women, to be chronic opioid users, to report more allergies, to have a diagnosis of anxiety, and to have shoulder pathology other than degenerative joint disease (all P ≤ .001). After multivariable adjustment, the presence of at least 1 functional somatic syndrome was independently predictive of lower 2-year ASES (-9.75 points) and SANE (-7.63 points) scores and greater residual pain (+1.13 points) (all P ≤ .001). When considered cumulatively, each additional functional disorder was linked to a stepwise decrease in ASES and SANE scores and an increase in residual pain (P < .001). These patients also incurred higher hospitalization costs, with a stepwise rise in costs with an increasing number of disorders (P < .001). CONCLUSIONS: Functional somatic syndromes are common in patients undergoing shoulder arthroplasty and correlate with suboptimal outcomes and greater resource utilization. Efforts to address the biopsychosocial determinants of health that affect the value proposition of shoulder arthroplasty should be prioritized in the redesign of care pathways and bundling initiatives.

The association between anterior shoulder joint capsule thickening and glenoid deformity in primary glenohumeral osteoarthritis.

BACKGROUND: Anterior shoulder joint capsule thickening is typically present in osteoarthritic shoulders, but its association with specific patterns of glenoid wear is incompletely understood. We sought to determine the relationship between anterior capsular thickening and glenoid deformity in primary glenohumeral osteoarthritis. METHODS: We retrospectively identified 134 consecutive osteoarthritic shoulders with magnetic resonance imaging and computed tomography scans performed. Axial fat-suppressed magnetic resonance imaging slices were used to quantify the anterior capsular thickness in millimeters, measured at its thickest point below the subscapularis muscle. Computed tomography scans were used to classify glenoid deformity according to the Walch classification, and an automated 3-dimensional software program provided values for glenoid retroversion and humeral head subluxation. Multinomial and linear regression models were used to characterize the association of anterior capsular thickening with Walch glenoid type, glenoid retroversion, and posterior humeral head subluxation while controlling for patient age and sex. RESULTS: The anterior capsule was thickest in glenoid types B2 (5.5 mm, 95% confidence interval [CI]: 5.0-6.0) and B3 (6.1 mm, 95% CI: 5.6-6.6) and thinnest in A1 (3.7 mm, 95% CI: 3.3-4.2; P < .001). Adjusted for age and sex, glenoid types B2 (odds ratio: 4.4, 95% CI: 2.3-8.4, P < .001) and B3 (odds ratio: 5.4, 95% CI: 2.8-10.4, P < .001) showed the strongest association with increased anterior capsule thickness, compared to glenoid type A1. Increased capsular thickness correlated with greater glenoid retroversion (r = 0.57; P < .001) and posterior humeral head subluxation (r = 0.50; P < .001). In multivariable analysis, for every 1-mm increase in anterior capsular thickening, there was an adjusted mean increase of 3.2° (95% CI: 2.4-4.1) in glenoid retroversion and a 3.8% (95% CI: 2.7-5.0) increase in posterior humeral head subluxation. CONCLUSIONS: Increased thickening of the anterior shoulder capsule is associated with greater posterior glenoid wear and humeral head subluxation. Additional research should determine whether anterior capsular disease plays a causative role in the etiology or progression of eccentric glenohumeral osteoarthritis.

Neighborhood socioeconomic disadvantage does not predict outcomes or cost after elective shoulder arthroplasty.

BACKGROUND: There is growing evidence that the variation in value of shoulder arthroplasty may be mediated by factors external to surgery. We sought to determine if neighborhood-level socioeconomic deprivation is associated with postoperative outcomes and cost among patients undergoing elective shoulder arthroplasty. METHODS: We identified 380 patients undergoing elective total shoulder arthroplasty (anatomic or reverse) between 2015 and 2018 in our institutional registry with minimum 2-year follow-up. Each patient's home address was mapped to the area deprivation index in order to determine the level of socioeconomic disadvantage. The area deprivation index is a validated composite measure of 17 census variables encompassing income, education, employment, and housing conditions. Patients were categorized into 3 groups based on socioeconomic disadvantage (least disadvantaged [deciles 1-3], middle group [4-6], and most disadvantaged [7-10]). Bivariate analysis was performed to determine associations between the level of socioeconomic deprivation with hospitalization time-driven activity-based costs and 2-year postoperative American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE), and pain intensity scores. RESULTS: Overall 19% of patients were categorized as most disadvantaged. These patients were found to have equivalent preoperative pain intensity (P = .51), SANE (P = .50), and ASES (P = .72) scores compared to the middle and least disadvantaged groups, as well as similar outcome improvement at 2 years postoperatively (ASES): least disadvantaged group [35.7-84.3], middle group [35.1-82.4], and most disadvantaged group [37.1-84.0] [P = .56]; SANE: least disadvantaged group [31.8-87.1], middle group [30.8-84.8], and most disadvantaged group [34.2-85.1] [P = .42]; and pain: least disadvantaged group [6.0-0.97], middle group [6-0.97], and most disadvantaged group [5.6-0.80] [P = .88]. No differences in hospitalization costs were noted between groups (P = .77). CONCLUSIONS: Patients undergoing elective shoulder arthroplasty residing in the most disadvantaged neighborhoods demonstrate equivalent preoperative and postoperative outcomes as others, without incurring higher costs. These findings support continued efforts to provide equitable access to orthopedic care across the socioeconomic spectrum.

Patients with limited health literacy have worse preoperative function and pain control and experience prolonged hospitalizations following shoulder arthroplasty.

BACKGROUND: Patients with limited health literacy (LHL) may have difficulty understanding and acting on medical information, placing them at risk for potential misuse of health services and adverse outcomes. The purposes of our study were to determine (1) the prevalence of LHL in patients undergoing inpatient shoulder arthroplasty, (2) the association of LHL with the degree of preoperative symptom intensity and magnitude of limitations, (3) and the effects of LHL on perioperative outcomes including postoperative length of stay (LOS), total inpatient costs, and inpatient opioid consumption. METHODS: We retrospectively identified 230 patients who underwent elective inpatient reverse or anatomic shoulder arthroplasty between January 2018 and May 2021 from a prospectively maintained single-surgeon registry. The health literacy of each patient was assessed preoperatively using the validated 4-item Brief Health Literacy Screening Tool. Patients with a Brief Health Literacy Screening Tool score ≤ 17 were categorized as having LHL. The outcomes of interest were preoperative patient-reported outcome scores and range of motion, LOS, total postoperative inpatient opioid consumption, and total inpatient costs as calculated using time-driven activity-based costing methodology. Univariate analysis was performed to determine associations between LHL and patient characteristics, as well as the outcomes of interest. Multivariable linear regression modeling was used to determine the association between LHL and LOS while controlling for potentially confounding variables. RESULTS: Overall, 58 patients (25.2%) were classified as having LHL. Prior to surgery, these patients had significantly higher rates of opioid use (P = .002), more self-reported allergies (P = .007), and worse American Shoulder and Elbow Surgeons scores (P = .001), visual analog scale pain scores (P = .020), forward elevation (P < .001), and external rotation (P = .022) but did not significantly differ in terms of any additional demographic or clinical characteristics (P > .05). Patients with LHL had a significantly longer LOS (1.84 ± 0.92 days vs. 1.57 ± 0.58 days, P = .012) but did not differ in terms of total hospitalization costs (P = .65) or total inpatient opioid consumption (P = .721). On multivariable analysis, LHL was independently predictive of a significantly longer LOS (ß, 0.14; 95% confidence interval, 0.02-0.42; P = .035). CONCLUSION: LHL is commonplace among patients undergoing elective shoulder arthroplasty and is associated with greater preoperative symptom severity and activity intolerance. Its association with longer hospitalizations suggests that health literacy is an important factor to consider for postoperative disposition planning.

Rotator cuff fatty infiltration and muscle atrophy: relation to glenoid deformity in primary glenohumeral osteoarthritis.

BACKGROUND: Muscle atrophy (MA) and fatty infiltration (FI) are degenerative processes of the rotator cuff musculature that have incompletely understood relationships with the development of eccentric glenoid wear in the setting of primary glenohumeral osteoarthritis (GHOA). METHODS: All patients with GHOA and an intact rotator cuff who underwent both magnetic resonance imaging and computed tomography scans of the affected shoulder prior to total shoulder arthroplasty between 2015 and 2020 were identified from a prospectively maintained registry. Rotator cuff MA was measured quantitatively on sequential sagittal magnetic resonance images, whereas FI was assessed on sagittal magnetic resonance imaging slices using the Goutallier classification. Preoperative computed tomography scans were reconstructed using automated 3-dimensional software to determine glenoid retroversion, glenoid inclination, and humeral head subluxation. Glenoid deformity was classified according to the Walch classification. Univariate and multivariable regression analyses were performed to characterize associations between age, sex, muscle area, FI, and glenoid morphology. RESULTS: Among the 127 included patients, significant associations were found between male sex and larger overall rotator cuff musculature (P < .01), increased ratio of the posterior rotator cuff (PRC) to the subscapularis area (P = .01), and glenoid retroversion (19° vs. 14°, P < .01). Larger supraspinatus and PRC muscle size was correlated with increased retroversion (r = 0.23 [P = .006] for supraspinatus and r = 0.25 [P = .004] for PRC) and humeral head subluxation (r = 0.25 [P = .004] for supraspinatus and r = 0.28 [P = .001] for PRC). The ratio of PRC muscle size to anterior rotator cuff muscle size was not associated with evidence of eccentric glenoid wear (P > .05). After we controlled for confounding factors, increasing glenoid retroversion was associated with high-grade infraspinatus FI (ß, 6.8; 95% confidence interval, 2.9-10.7; P < .01) whereas larger PRC musculature was predictive of a Walch type B (vs. type A) glenoid (odds ratio, 1.3; 95% confidence interval, 1.0-1.5; P = .04). CONCLUSION: Patients with eccentric glenoid wear in the setting of primary GHOA and an intact rotator cuff appear to have both larger PRC musculature and higher rates of infraspinatus FI. Although the temporal and causal relationships of these associations remain ambiguous, MA and FI should be considered 2 discrete processes in the natural history of GHOA.

A validated algorithm using current literature to judge the appropriateness of anatomic total shoulder arthroplasty utilizing the RAND/UCLA appropriateness method.

BACKGROUND: Currently, appropriateness criteria evaluating when to perform total shoulder arthroplasty (TSA) is lacking. In the absence of society guidelines and limited quality evidence, the RAND/University California in Los Angeles (UCLA) method provides a suitable alternative to evaluate appropriateness and assist in clinical decision making. Given the rise in utilization, appropriateness criteria for TSA have the potential to be an extremely powerful tool for improving quality of care and controlling costs. Thus, the goal of this study was to test explicit criteria to assess the appropriateness of TSA decision making using the RAND/UCLA appropriateness method. METHODS: A review of recent scientific literature to gather available evidence about the use, effectiveness, efficiency, and the risks involved in surgical intervention was performed by a shoulder/elbow fellowship trained physician. Based on pertinent variables including age, rotator cuff status, previous surgical management, mobility, symptomatology, and imaging classifications, 186 clinical scenarios were created. Appropriateness criteria for TSA were developed using a modified Delphi method with a panel consisting of American Shoulder and Elbow Surgeons (ASES) members. A second panel of ASES members rated the same scenarios, with reliability testing performed to compare groups. RESULTS: Panel members reached agreement in 40 (64%) indications. TSA was appropriate in 15 (24%) of indications. For patients with severe symptomatology, TSA was often appropriate for patients aged <75 years and inconclusive or inappropriate for patients aged >75 years. Among patients aged <65 years, TSA varied between appropriate and inconclusive, often dependent on Walch classification. For patients with moderate symptomatology, TSA was inappropriate or inconclusive for patients aged <65 or >75 years. When compared to the second panel's results, moderate agreement was obtained with a weighted kappa statistic of 0.56. CONCLUSIONS: Using the RAND/UCLA method, ASES members created an appropriateness decision tree for pertinent patient variables. This presents the data in a manner that streamlines the clinical decision-making process and allows for rapid and more reliable determination of appropriateness for practitioners. The decision tree is based on a combination of clinical experience from high-volume ASES-member surgeons and a comprehensive review of current evidence. This tool can be used as part of a broader set of factors, including individual patient characteristics, prior studies, and expert opinion, to inform clinical decision making, improve quality of care, and control costs.

Impact of the COVID-19 pandemic on shoulder arthroplasty: surgical trends and postoperative care pathway analysis.

BACKGROUND: COVID-19 triggered disruption in the conventional care pathways for many orthopedic procedures. The current study aims to quantify the impact of the COVID-19 pandemic on shoulder arthroplasty hospital surgical volume, trends in surgical case distribution, length of hospitalization, posthospital disposition, and 30-day readmission rates. METHODS: This study queried all Medicare (100% sample) fee-for-service beneficiaries who underwent a shoulder arthroplasty procedure (Diagnosis-Related Group code 483, Current Procedural Terminology code 23472) from January 1, 2019, to December 18, 2020. Fracture cases were separated from nonfracture cases, which were further subdivided into anatomic or reverse arthroplasty. Volume per 1000 Medicare beneficiaries was calculated from April to December 2020 and compared to the same months in 2019. Length of stay (LOS), discharged-home rate, and 30-day readmission for the same period were obtained. The yearly difference adjusted for age, sex, race (white vs. nonwhite), Centers for Medicare & Medicaid Services Hierarchical Condition Category risk score, month fixed effects, and Core-Based Statistical Area fixed effects, with standard errors clustered at the provider level, was calculated using a multivariate analysis (P < .05). RESULTS: A total of 49,412 and 41,554 total shoulder arthroplasty (TSA) cases were observed April through December for 2019 and 2020, respectively. There was an overall decrease in shoulder arthroplasty volume per 1000 Medicare beneficiaries by 14% (19% reduction in anatomic TSA, 13% reduction in reverse shoulder arthroplasty, and 3% reduction in fracture cases). LOS for all shoulder arthroplasty cases decreased by 16% (-0.27 days, P < .001) when adjusted for confounders. There was a 5% increase in the discharged-home rate (88.0% to 92.7%, P < .001), which was most prominent in fracture cases, with a 20% increase in discharged-home cases (65.0% to 73.4%, P < .001). There was no significant change in 30-day hospital readmission rates overall (P = .20) or when broken down by individual procedures. CONCLUSIONS: There was an overall decrease in shoulder arthroplasty volume per 1000 Medicare beneficiaries by 14% during the COVID-19 pandemic. A decrease in LOS and increase in the discharged-home rates was also observed with no significant change in 30-day hospital readmission, indicating that a shift toward an outpatient surgical model can be performed safely and efficiently and has the potential to provide value.