Bicompartmental versus total knee arthroplasty for medio-patellofemoral osteoarthritis: a comparison of early clinical and functional outcomes.

Severe medio-patellofemoral osteoarthritis (MPFOA) is often managed with a total knee arthroplasty (TKA). Bicompartmental knee arthroplasty (BKA), as compared with TKA can offer a bone and ligament preserving solution for MPFOA. We aimed to compare the early clinical and functional outcomes of modular BKA (n = 16) with TKA (n = 20) in MPFOA. Knee Society Score (KSS-clinical and function scores) and Knee injury & Osteoarthritis Outcome Score (KOOS-pain, symptoms, stiffness, and function scores) were recorded at 6, 12 and 24 months postoperatively and compared between the two groups. Pre- and postoperative radiographs were evaluated for alignment and radiolucencies. We found that none of the outcome scores were significantly different (p ≥ 0.137) between the two groups at any point in time. Postoperative knee range of motion (ROM) was significantly greater in the BKA group at all points in time (p ≤ 0.007). None of the patients in either group were revised or pending revision at the end of 24 months. To conclude, modular BKA resulted in better knee ROM but similar clinical and functional scores than TKA in MPFOA at short term. Modular BKA is a viable option for MPFOA but may not necessarily result in significant superior functional outcomes than with TKA.