A national shift to outpatient total shoulder arthroplasty in the United States after regulatory changes: a 10-year analysis of current trends in procedure volume, complications, and health-care utilization

Background: On January 1, 2021, total shoulder arthroplasty (TSA) was removed from the Medicare “Inpatient Only List”, allowing for reimbursement of outpatient TSA and broadening patient access to outpatient TSA for patients on these insurances. The purpose of this study is to analyze the trends in inpatient vs. outpatient TSA due to the regulatory change in reimbursement. In addition, we analyze differences in 30-day postoperative complications following inpatient vs. outpatient TSA. Methods: All patients who underwent TSA between 2011 and 2022 were queried from the American College of Surgeons National Surgical Quality Improvement Program database. Postoperative complications were reported within 30 days of procedure. Goodness-of-fit Chi-square test with summary statistics was employed to identify differences in 30-day complications, readmissions, and reoperations between cohorts. Statistical significance was assessed at P = .05. Results: A total of 45,986 patients underwent TSA between 2011 and 2022. 74.7% (n = 34,341) underwent inpatient TSA. The annual volume of inpatient TSA from 2020 to 2022 had a 50% decrease (3552 to 1779). The annual volume of outpatient TSA increased by 449% (885 to 4861) during the same period. Compared to patients who underwent inpatient TSA from 2011 to 2020, the 2021-2022 inpatient TSA cohort were more likely to be age ≥75 years (P < .001), female gender (P < .001), body mass index ≥35 (P < .001), American Society of Anesthesiologists ≥3 (P < .001), dependent functional status (P < .001), and had significantly higher comorbidities including diabetes (P = .005), chronic obstructive pulmonary disease (P < .001), hypertension (P < .001), steroid use (P < .001), and bleeding disorder (P = .050). Amongst all outpatient TSA, patients from 2021 to 2022 were more likely to be age ≥65 years (P < .001), female gender (P < .001), body mass index ≥35 (P = .001), American Society of Anesthesiologists ≥3 (P < .001), dependent functional status (P < .001), and had significantly higher comorbidities including diabetes (P < .001), chronic obstructive pulmonary disease (P < .001), congestive heart failure (P = .014), and hypertension (P = .039). The outpatient cohort had fewer 30-day complications and reoperations in both 2011-2020 and 2021-2022. Both inpatient and outpatient hospital length of stay decreased over time; however, the outpatient cohort had shorter hospital length of stay (P < .001). Mean operative time for inpatient TSA increased from 109.43 minutes (2011-2020) to 112.91 minutes (2021-2022), while the mean outpatient TSA operative time decreased from 113.86 to 102.94 minutes during the same time periods (P < .001). Conclusions: The volume of outpatient TSA increased nearly fivefold after its removal from the Inpatient Only List list in 2021. Despite increasing volume of outpatient TSA, the overall 30-day postoperative complications and reoperations remain low. These findings indicate that performing TSA in an outpatient setting remains safe with appropriate perioperative patient selection.