Chiari pelvic osteotomy in children and young adults.

We conducted a follow-up study of twenty-four patients who had been treated with a Chiari osteotomy at the Alfred I. duPont Institute between 1966 and 1981. The length of follow-up ranged from three to twenty years, and the age at operation ranged from ten to twenty-three years. The indication for the operation was either painful dysplasia or gross instability of the hip. Twelve patients had had congenital dislocation of the hip; six, poliomyelitis; three, cerebral palsy; and three had had another disorder. A good or excellent result was obtained in twenty-one of the twenty-four patients. Preoperative pain and antalgic gait were consistently improved. In twenty-one patients, the osteotomy had to be displaced more than 50 per cent to provide adequate coverage of the femoral head, and bone-grafting was necessary at the site of the osteotomy to prevent problems with healing.