Outcome of Unconstrained Total Knee Replacement in Osteoarthritis (OA) Knee with Severe Varus Deformity in Rural West Bengal

Abstract

Severe genu varus deformity in osteoarthritis knee presents significant surgical challenge in achieving optimal alignment and functional recovery. Evidence from rural Indian populations remains limited. To evaluate functional, radiological, and mental health outcomes following unconstrained total knee replacement (TKR) in patients with severe varus deformity from rural low socioeconomic backgrounds. This prospective non-randomized interventional study was conducted over 2year at a tertiary care centre in rural West Bengal. A total of 54 TKRs in fifty patients (50) with osteoarthritis knee with varus deformity >30° were included. Outcomes were assessed using Knee Society Score (KSS), Functional Knee Score (FKSS), Oxford Knee Score (OKS), SF-12 Physical (PCS) and Mental Component Scores (MCS), and tibiofemoral angle (TFA). Socioeconomic status was evaluated using Modified Kuppuswamy Scale. Significant improvement was observed in all functional parameters. Mean ROM improved from 85.5° to 119.1°. KSS increased from 37.4 to 81.8, FKSS from 32.7 to 72.6, and OKS from 13.7 to 36.8 (p<0.001). SF-12 PCS and MCS showed marked improvement. Mean TFA corrected from 30.7° varus to 4.1° valgus. Lower socioeconomic status showed significant negative correlation with KSS and FKSS, indicating better outcomes. Unconstrained TKR provides significant functional, radiological, and psychological improvement in severe varus knees, particularly in rural low socioeconomic populations.