[Outcome at more than 10 years of 93 tibial osteotomies for internal arthritis in genu varum (or the predominant influence of the frontal angular correction)].

Ninety three high tibial valgus osteotomies have been performed by the authors for degenerative arthritis and reviewed more than 10 years later. The mean age of the 66 patients was 70 years. The results were somewhat disappointing. Seventeen knees had to be operated on before the tenth post-operative year and only 42 knees were painless at the time of review. Radiological improvement in the medial tibio-femoral joint was rarely seen. Fortunately, deterioration in the lateral tibio femoral joint was exceptional and joint laxity was rarely troublesome. The authors conclude that the amount of correction at the time of the osteotomy is of extreme importance. The results were satisfactory only in cases where valgus ranging between 3 and 6 degrees had been obtained. When an osteotomy produced a greater amount of valgus, deterioration of the lateral tibio-femoral joint was seen. When the osteotomy produced less than 3 degrees of valgus, recurrence of the varus deformity developed. In these cases, functional deterioration was noted after seven years. Thus, the osteotomy appeared to have slowed down the natural evolution of the disease. The results of valgus osteotomy were satisfactory in most of the cases, but they were excellent only in cases in which a valgus ranging from 3 to 6 degrees had been produced. The importance of a precise radiological measurement is stressed, the accuracy of measurement being doubtful in cases with associated flexion deformity or joint laxity. The precision of the surgical procedure is also very important.