Bicompartmental arthroplasty of the knee.

Combined replacement of the patellofemoral and medial tibiofemoral joints has been performed in the past. The original approaches placed two separate implants during the same surgical procedure. Results were acceptable; however, with the increasing success of total knee arthroplasty, partial knee replacements lost favor. In the 1990s, a limited incision for unicondylar arthroplasty was introduced that encouraged interest in partial knee replacements. The newer implants combine the medial and patellofemoral articulations into a single femoral implant with a medial tibial tray and a polyethylene patella. The surgical technique and instruments are somewhat unique and training is helpful. Bicompartmental arthroplasty preserves all of the ligaments of the knee while replacing two compartments. The procedure is more complicated than unicompartmental knee arthroplasty, less invasive than total knee arthroplasty, and may have a place in replacement surgery.