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.