The safety and efficacy of a new adjustable plate used for proximal tibial opening wedge osteotomy in the treatment of unicompartmental knee osteoarthrosis.

Twenty opening wedge tibial osteotomies were performed using the Osteotrac plate, which consists of a two-piece plate with a one-way ratcheting mechanism with two degrees of freedom. A variety of concomitant procedures were performed including osteochondral transfer, tibial tubercle medialization, and anterior cruciate ligament reconstruction. The change in tibiofemoral alignment in the coronal plane and the shift in lower extremity mechanical axis were determined. The average lateral shift in the lower extremity mechanical axis was 24% of the tibial plateau width. The average change in the mechanical tibiofemoral angle was 7 degrees of valgus. Union rate at the osteotomy site was 95%. No deep infections, clinical deep venous thrombosis, or device failures occurred. The Osteotrac plate provides safe and effective fixation and intraoperative adjustability to achieve and maintain a lateral shift of the lower extremity mechanical axis and valgus correction of the tibiofemoral alignment in patients with varus knees undergoing proximal tibial opening wedge osteotomy and associated meniscal and chondral procedures.