Effectiveness of femoral varus osteotomy in patients with cerebral palsy.

This is a retrospective review of 144 hips in 99 patients treated with femoral varus osteotomy between 1975 and 1995. Average follow-up was 5 years (range, 2-15 years). The majority of patients (67%) were nonambulatory spastic quadriparetics. The average age at the time of surgery was 7.7 years (range, 3-15 years). Radiographic parameters analyzed were the neck-shaft and center-edge (CE) angles and Reimer's migration index (MI). Results were considered good if the CE angle was >20 degrees and the MI <30%, fair if the CE angle was 0 degrees - 20 degrees and the MI 30-50%, and poor if the patient had persistent pain, a CE angle of <0 degrees , or an MI >50%. Twelve hips (8%) remained painful at final follow-up, and 12 hips (8%) dislocated despite surgery. Previous surgery, unilateral surgery, performing a pelvic osteotomy, and age at the time of surgery had no statistical influence on outcome. Good results were obtained in 43.1%, fair in 41.5%, and poor in 15.4%. Only the quality of the reduction obtained at surgery, judged by the increase in CE angle and the reduction in MI, had a statistical influence on final result. Athetoid patients fared as well as those with spasticity. Femoral varus osteotomy was effective in providing a stable pain-free hip in 84% of patients.