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

Abstract

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. 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. 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 (<i>p</i> < 0.001), had lower body mass index (BMI) (<i>p</i> = 0.010), and had lower American Society of Anesthesiologists (ASA) scores (<i>p</i> = 0.030). They were more likely to have a prolonged LOS (<i>p</i> < 0.001) and be discharged to skilled nursing facility or rehab facility (<i>p</i> < 0.001). Total LOS for separate hospitalizations in staged procedures was greater than LOS for same-day bilateral TKAs (<i>p</i> < 0.001). There was no difference in 90-day ED visits (<i>p</i> = 0.623) or readmission (<i>p</i> = 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. 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.