The aim of this study is to evaluate the mid-term results of the Genesis I Total Knee prosthesis (asymmetric tibial component plateaus), retaining the posterior cruciate ligament and not resurfacing the patella in all patients.

Between 1992 and 1999, 90 patients (116 knees) were operated (81 women and 9 men) of an average age of 68 (52–82) years. The indication for the operation was osteoarthritis. 84 patients (109 knees) were evaluated clinically and roentgenographically (Knee Society Knee Score). The average follow-up time was 74.1 (29.6–113.7) months.

There were no cases of infections. Three of the patients required a second operation. Two of them had their patellae replaced (1,5 and 3 years postoperatively) due to persisting patellofemoral pain. In a third patient the knee was revised due to excessive wear of the polyethylene component five years postoperatively. Moreover, major polyethylene wear was also observed six years postopertively on another patient, asymptomatic and unwilling to undergo a revision. The clinical results were satisfactory with a mean Knee Score of 97 (74–100) and a Function Score of 80 (5–100). The mean range of motion was 113° (85°–135°). There was no evidence of loosening or any radiolucent line found radiographically.

We consider the results of the Genesis I Total Knee Arthroplasty satisfactory. The asymmetric shape of the tibial condyles ensures the fitting of the tibial component. Even in cases of severe patella damage, we believe that replacement of the patella is not required. Occurrence of patellofemoral problems can be usually attributed to mal-tracking of the patella or to component malposisioning.