Early Adverse Results with Bicompartmental Knee Arthroplasty: A Prospective Cohort Comparison to Total Knee Arthroplasty

This prospective cohort study compares functional outcomes of bicompartmental knee arthroplasty (BKA) and total knee arthroplasty (TKA) in patients with osteoarthritis (OA) of the patellofemoral and medial compartments. Eligibility criteria included bicompartmental OA with less than grade 2 OA in the lateral compartment and intact cruciate ligaments. Fifty-six patients met eligibility criteria (21 BKA, 33 TKA). Enrolled participants completed Short-Form 12 and Western Ontario and McMaster Universities Osteoarthritis Index assessments at baseline and postoperatively at 3 months, 1 year, and 2 years. In the early postoperative period, the BKA cohort had significantly less pain (P = .020) and better physical function (P = .015). These trends did not continue past 3 months. When adjusting for age, sex, body mass index, and preoperative status, only 3-month Western Ontario and McMaster Universities Osteoarthritis Index stiffness scores significantly differed between cohorts (P = .048). Despite less early stiffness in the BKA cohort, a significantly higher BKA complication rate (P = .045) has led us to recommend TKA for patients with this pattern of OA.