Comparisons of satisfaction rates following total knee arthroplasty (TKA) among large, age-differentiated, rigorously matched cohorts are lacking. Therefore, we compared satisfaction rates following TKA in large, age-differentiated, propensity score-matched cohorts.
We identified primary TKAs performed for non-inflammatory arthritis in patients of ages 18-55 or 65-75, yielding 529 younger and 2001 older patients. Patient-reported outcomes were recorded pre-operatively and 2 years post-operatively. 1:1 propensity score matching between groups yielded 529 patient pairs. Matching was based on gender, body mass index, American Society of Anesthesiologists grade, Charlson Comorbidity Index, and Short Form 12 Mental Health Component score. Outcomes were compared between matched groups using t-test and Wilcoxon rank-sum test.
Satisfaction with knee surgery was 86% among younger patients and 91% among older patients. Distribution of satisfaction responses was shifted toward greater satisfaction in older patients (P < .001). Overall quality of life (QOL) improvement was 91% among younger patients and 96% among older patients. Pre-operative and post-operative knee-related QOL was better among older patients (P < .0001). Post-operative global health-related QOL was equivalent between groups based on Short Form 12 Physical Component Score and Mental Health Component score (P = .6646 and P = .5705, respectively) and QOL improvement questionnaires (P = .181). Younger patients reported greater knee-related dysfunction and higher activity levels pre-operatively and post-operatively (P ≤ .0002).
Satisfaction with knee surgery was over 85% regardless of age. Younger patients perceived more knee-related dysfunction and dissatisfaction after surgery despite higher levels of self-reported activity pre-operatively and post-operatively.