Short Term Results of Oxford Unicompartmental Knee Arthroplasty

ABSTRACT

PURPOSE: To report the results of Oxford unicompartmental knee arthroplasty after short term follow up. MATERIALS AND METHODS: Twenty nine knees from 26 patients who had undergone Oxford unicompartmental knee arthroplasty from March 2002 to February 2006 were reviewed. There were 25 females (28 knees) and 1 male (1 knee) and the average age was 65.9 years. The preoperative diagnosis was 22 cases of medial osteoarthritis and 7 cases of osteonecrosis of the medial femoral condyle. We evaluated the intraoperative complications. The clinical evaluation was accomplished by assessing the pre-and postoperative knee society pain and function scores, Lysholm score and HSS score. The radiologic evaluation was accomplished using the weight bearing AP view and lateral films. RESULTS: The postoperative knee society pain and function score, Lysholm score and HSS score were improved compared with the preoperative scores. The tibiofemoral angle was improved from varus 2.8degrees preoperatively to valgus 6.6degrees. Three cases of medial tibial condyle fracture occurred and 1 case of overhang of the tibial component were observed. Three cases were revised due to component loosening. CONCLUSION: Even though a high incidence of complications and loosening were observed, the clinical results of Oxford unicompartmental knee arthroplasty were improved during the short term follow up. We thought that thorough preparations should be done prior to surgery and there is room to improve femoral component design for the stability against rotational torque such as two pegs on the femoral component.