High tibial osteotomy combined with anterior displacement of the tibial tubercle for osteoarthritis of the knee.

Eighty-nine knees with medial tibio-femoral and patellofemoral osteoarthritis were treated by high tibial osteotomy between 1972 and 1978, and 71 were followed up for at least 5 years, the average being 6 years and 9 months. There was no significant loss of motion as recorded before and after operation. In most patients pain decreased or disappeared, and walking ability was regained. Evaluation using the Japanese rating system showed that there were Good and Fair results in 86% of the cases. The average tibio-femoral angle in the Good group was 169 +/- 5 degrees. The angles in the Poor group varied over a wide range. There were serious complications such as nonunion, malunion and infection in a few cases. In Group 1 (30 knees) high tibial osteotomy alone was performed. In Group 2 (41 knees) there were associated osteoarthritic changes in the patellofemoral joint and a high tibial osteotomy was combined with anterior displacement of the tibial tubercle (ventralization). In comparison, Group 2 had better results with regard to both clinical and radiological evaluation.