Treatment of hip subluxation in skeletally mature patients with cerebral palsy.

Hip subluxation is common in children with spastic cerebral palsy. Most physicians favor intervention to treat hip subluxation in skeletally immature patients with cerebral palsy. However, treatment in skeletally mature patients with cerebral palsy is controversial. The goal of this study was to evaluate radiographic and clinical outcomes after hip reconstruction in skeletally mature patients with cerebral palsy. The authors performed a retrospective review of all skeletally mature patients (n=20) with cerebral palsy who underwent hip surgery for subluxation at the authors' institution between 2005 and 2011. Charts were reviewed for demographic characteristics, procedure, follow-up, and complications. Acetabular index, migration index, and neck-shaft angle were measured on preoperative and most recent radiographs. Average follow-up was 2.2 years. Average migration index for the entire group improved from 57% to 20% (P<.0001). Of patients who had all radiographic abnormalities addressed at surgery (varus derotational femoral osteotomy for neck-shaft angle >135°, open reduction for migration index >50%, and acetabular osteotomy for acetabular index >25°), 91% had a final migration index of less than 25%. In patients who did not have all radiographic abnormalities addressed, 33% had a migration index of less than 25% at final follow-up. No intraoperative complications occurred; however, 13 patients had at least 1 postoperative complication. Hip subluxation in skeletally mature patients with cerebral palsy is difficult to treat and is associated with a high incidence of complications. The likelihood of a successful outcome appears to be related to the appropriateness of the surgical procedure. When all radiographic abnormalities were addressed during surgery, a successful radiographic outcome at final follow-up was much more likely than when intervention was less comprehensive.