Ninety-Day Readmissions and Resource Utilization After Hip Resurfacing Versus Total Hip Arthroplasty in Patients Aged 45-65 Years: A Propensity Score-Matched Analysis of the Nationwide Readmissions Database

Background Hip resurfacing arthroplasty (HRA) is selectively used for younger, active patients with hip osteoarthritis as a bone-preserving alternative to conventional total hip arthroplasty (THA). Contemporary national data comparing short-term, episode-of-care outcomes-including 90-day readmission and readmission resource utilization-remain limited in typical resurfacing-eligible patients. Methods We performed a retrospective cohort study using the Nationwide Readmissions Database (NRD), 2020–2022. Elective, osteoarthritis-related primary hip arthroplasty admissions with the procedure performed on hospital day 0 were identified. The analytic cohort was restricted to males aged 45–65 years. Patients undergoing HRA were compared with those undergoing THA using 1:5 nearest-neighbor propensity score matching without replacement, incorporating demographics, payer, calendar year, residence category, hospital characteristics, and comorbidities (obesity, hypertension, dyslipidemia, obstructive sleep apnea, chronic anemia, osteoporosis, type 2 diabetes mellitus, chronic kidney disease, congestive heart failure, and chronic lung disease). The primary endpoint was all-cause 90-day readmission. Secondary outcomes included index hospitalization length of stay and charges, selected in-hospital complications, and readmission-level utilization among readmitted patients. Results The matched cohort included 3,398 admissions (THA n = 2,844; HRA n = 553). Baseline balance was achieved after matching. Index hospitalization charges were higher for HRA ($84,555 ± 49,002) than THA ($66,260 ± 39,393; p < 0.001), while index length of stay was slightly longer after THA (1.37 ± 1.46 vs 1.21 ± 1.12 days; p = 0.018). In-hospital mortality was not observed. Blood loss anemia occurred more frequently after THA (8.9% vs 5.1%; p = 0.003). Ninety-day readmission occurred in 2.7% after THA and 3.1% after HRA, with no statistically significant difference (p = 0.596). Among readmitted patients, readmission length of stay (5.65 ± 5.23 vs 3.01 ± 3.22 days; p = 0.010) and charges ($77,852 ± 68,606 vs $44,114 ± 25,112; p = 0.001) were higher after THA, while time to readmission and the proportion with any inpatient procedure during readmission were similar. Conclusions In males aged 45–65 years undergoing elective, same-day primary hip arthroplasty, HRA was associated with higher index hospitalization charges but similar 90-day readmission rates compared with THA. Among patients who were readmitted, THA was associated with greater readmission resource utilization. These findings provide contemporary national episode-of-care benchmarks and support nuanced, value-informed counseling in appropriately selected candidates. Levels of Evidence: Level III