Oxford Phase 3 Unicompartmental Knee Arthroplasty: Minimum 5-year Follow-up Results

ABSTRACT

PURPOSE: We wanted to evaluate the postoperative clinical results, the complications and the survival rate of Oxford phase 3 unicompartmental knee arthroplasty (UKA), based on a prospective analysis and the follow-up study. MATERIALS AND METHODS: We operated on 142 patients, 180 cases of UKA using the Oxford phase 3 prosthesis from January 2002 to December 2002. Clinical assessments were made using the Knee Society score rating system. Among those, 152 cases (121 patients) were able to be followed up for at least 5 years after the operation. The mean patient age at the time of surgery was 61.1 years and the mean duration of follow-up was 5.5 years. RESULTS: For these 152 knees, the mean preoperative knee and function scores were 53.5 and 55.8, respectively, and they were improved to 88.7 and 83.1, respectively, at the last follow-up. The mean range of knee motion recovered to 133.1degrees and the mean tibiofemoral angle was changed to 4.9degrees of valgus. When we asked patients about their level of satisfaction, 88% of the patients said they were 'very satisfied' or 'satisfied'. There were 7 postoperative complications and the survival rate of the implant at 5 years was 96.8%. CONCLUSION: The Oxford phase 3 UKA was satisfactory for improving the clinical results, the subjective satisfaction of the patients and the survival rate of the implant.