Equivalence of Outcomes Between Ambulatory and Hospital-Based Arthroplasty in Younger and Older Adults.

BACKGROUND: Total joint arthroplasty (TJA) has increasingly shifted toward ambulatory surgery centers (ASCs), yet data supporting the safety of this setting for older patients remain limited. This study compared 90-day perioperative outcomes of TJA performed at ASCs versus inpatient hospital settings, stratified by patients younger than 75 and those 75 years or older.

METHODS: We conducted a retrospective cohort study of 10,804 patients undergoing elective primary total hip or knee arthroplasty between 2021 and 2023 at a single academic health system. Patients were stratified by surgical setting (ASC versus hospital) and age group (less than 75 versus ≥ 75 years). Propensity score matching (3:1) was performed using age, sex, race, and Body Mass Index (BMI), yielding 7,150 patients for analysis. The 90-day outcomes included readmissions, emergency department (ED) visits, reoperations, periprosthetic joint infections, dislocations, and periprosthetic fractures.

RESULTS: The ASC patients had significantly shorter lengths of stay, shorter procedure durations, and higher rates of home discharge in both age groups. Among patients ≥ 75 years of age, no significant differences were found in 90-day readmissions (3.6 versus 1.8%, P = 0.15), ED visits (11 versus 12%, P = 0.9), or major complications, including PJI and dislocation. In the under-75 year group, unplanned reoperation (1.6 versus 0.9%, P = 0.032) and readmission rates (1.8 versus 0.9%, P = 0.008) were slightly higher in ASC patients, though absolute rates remained low.

CONCLUSION: The ASC-based TJA demonstrated comparable 90-day outcomes to inpatient surgery in both older and younger adults. Age alone should not preclude patients from ASC consideration for total joint arthroplasty. Site-of-care decisions should be driven by individual physiologic fitness rather than chronological age cutoffs.