Triplane osteotomy for severely slipped upper femoral epiphysis.

Intertrochanteric osteotomy gives compensatory correction for the severely slipped upper femoral epiphysis without endangering its blood supply. The results of thirty-five such osteotomies carried out over an eighteen-year period are reviewed. The indication for operation was a chronic slip of a third or more of the growth plate in the lateral radiograph. The mean age at operation was fourteen years and the mean follow-up period seven and a half years. The results showed that even a moderate correction of deformity as shown by the radiograph could produce a hip with a functionally satisfactory range of movement. Chondrolysis was the most serious complication and occurred in four hips. The radiological results are discussed in relation to details of operative technique and also to long-term prognosis.