Same-day Bilateral Total Knee Arthroplasty Did Not Increase 90-day Hospital Returns

Abstract

Purpose: Bilateral total knee arthroplasty (TKA) can be performed in patients with bilateral knee arthritis. Outside of nationwide database studies, which have limitations, few studies have compared outcomes for same-day versus staged TKA. We sought to compare patient outcomes at a single tertiary referral center. Methods: The institutional database was queried from March 2014 to December 2017 for primary TKA. Patients undergoing bilateral procedures were stratified by same-day versus staged; length of stay (LOS), disposition, 90-day emergency department (ED) visits, and 90-day readmissions were examined through univariable and multivariable analyses. Results: A total of 676 patients were evaluated (113 same-day and 563 staged bilateral TKA patients) with mean age 66.0 (8.5) at first surgery and 292.1 (241.6) days between staged procedures. Same-day bilateral TKA patients were younger ( p < 0.001), had lower body mass index (BMI) ( p = 0.010), and had lower American Society of Anesthesiologists (ASA) scores ( p = 0.030). They were more likely to have a prolonged LOS ( p < 0.001) and be discharged to skilled nursing facility or rehab facility ( p < 0.001). Total LOS for separate hospitalizations in staged procedures was greater than LOS for same-day bilateral TKAs ( p < 0.001). There was no difference in 90-day ED visits ( p = 0.623) or readmission ( p = 0.286). In a multivariable model controlling for age, BMI, and ASA score, same-day bilateral TKA was not significantly associated with ED visits or readmissions. Conclusions: Patients undergoing same-day bilateral TKAs were more likely to be discharged to post-acute care facilities, however they did not have increased 90-day readmissions.