Factors Affecting the Length of Convalescent Hospital Stay Following Total Hip and Knee Arthroplasty

OBJECTIVES: : An important role of convalescent rehabilitation wards is the short-term improvement of mobility and activities of daily living (ADL). We aimed to identify predictors associated with the length of stay (LOS) in a convalescent hospital after total hip and knee arthroplasty. METHODS: : This study included 308 patients hospitalized in a convalescent ward following total hip or total knee arthroplasty. The following factors were examined: age, sex, orthopedic comorbidities, motor component of the functional independence measure (M-FIM), M-FIM gain, pain, 10-m walk test, timed up and go (TUG) test, functional ambulation category (FAC), cognitive function, and nutritional status. LOS was categorized as shorter (≤40 days) or longer (>40 days), based on the national average LOS in a convalescent ward, and was statistically analyzed with predictor variables. RESULTS: : In our hospital, the average LOS was 36.9 ± 21.4 days, and the average M-FIM at admission to the convalescent ward and the M-FIM gain were 71.1 ± 7.0 and 16.3 ± 6.9, respectively. In univariate analysis, there was a significant correlation between LOS and M-FIM at admission and M-FIM gain, pain, TUG time, and FAC. Logistic multivariate analysis identified M-FIM at admission (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.88–0.98) and TUG time (OR 1.10, 95% CI 1.03–1.18) as independent predictors of LOS. CONCLUSIONS: : The M-FIM and TUG test can be used to accurately estimate LOS and to plan rehabilitation treatment in a convalescent rehabilitation ward after lower-limb arthroplasty. Furthermore, preoperative or early postoperative intervention may lead to better quality motor activity and shorter LOS during the convalescent period.