[Surgical correction of osteoarthritic genu varum by the hemicallotasis technique].
PURPOSE OF THE STUDY: The aim of this short study is to highlight the role of the hemicallotasis method in correcting genu varum associated with osteoarthritis. MATERIAL AND METHOD: 160 cases are described. The first step was to apply a Dynamic Axial Fixator (DAF) with a lockable ball joint. A metaphyseal osteotomy was performed proximal to the anterior tuberosity of the tibia together with an osteotomy of the middle third of the fibula. After an initial 10 to 12 day neutralization period, distraction began with gradual axial correction to achieve an over correction of 2-3 degrees valgus. This was confirmed by a full limb radiograph allowing evaluation of the mechanical axes. The mean duration of distraction in this series was 14 days and the fixator was removed on the average at 3 months. Partial weight bearing was allowed with crutches on the first postoperative day. RESULTS: Preliminary clinical and radiographic review of 58 patients with an average follow-up of 18 months showed satisfactory results in 80 per cent of the cases. Clinical evaluation was performed with the standardized parameters in use at the Hospital for Special Surgery. Only 2 postoperative complications of any importance occurred, requiring early removal of the fixator. DISCUSSION: Comparison of the hemicallotasis method with traditional methods highlights the quick easy application of the technique with the possibility of gradual axial correction and early weight bearing. In addition, the technique does not preclude subsequent total knee replacement. CONCLUSION: The authors conclude that the method is safe particularly when the indication is well determined.