We reviewed 21 knees of 14 patients who underwent unicompartmental knee arthroplasty (UKA) for gonarthrosis in the medial compornent between 1992 and 1996. The mean age at surgery was 64 years with the postoperative follow-up period averaged at 32 months. Good clinical results were obtained and the average JOA score improved from 58 to 88 points. However the femorotibial angle (FTA) tended to increase gradually, despite the degree of corrected FTA (average 176). Patients requiring revision or with steep increase of FTA showed obesity, high performance ADL, or injury in the anterior cruciate ligament. In conclusion, UKA may have an indication only for elderly patients with low daily activity.
