Chiari osteotomy in the treatment of congenital dislocation and subluxation of the hip.

Twenty-nine Chiari osteotomies (eleven in children and eighteen in adolescents and adults) were critically reviewed after a minimum follow-up of two years and an average follow-up of 4.6 years. In four patients with complete dislocation and seven with moderate or severe subluxation, operations performed between the ages of four and fifteen years yielded five excellent or good results, three fair results, and three poor results. In the eighteen adolescent and adult patients, all of whom had pain, there were eleven good, two fair, and five poor results, the poor results being due to technical errors for the most part. The identified technical pitfalls were too low an osteotomy and too much displacement of the osteotomized fragments.