Surgical management of hip subluxation and dislocation in children with cerebral palsy: isolated VDRO or combined surgery?

Abstract

Background: Controversy exists regarding surgical treatment of hip subluxation/dislocation in children with cerebral palsy (CP). The purpose of this study was to compare isolated varus derotational osteotomy (VDRO) and VDRO combined with open hip reduction and/or pelvic osteotomy in children with CP and hip subluxation/dislocation.

Methods: Retrospective review was performed of 75 patients with CP (116 hips) and hip subluxation/dislocation treated surgically, with a minimum of 2 years follow-up. Ninety-two hips had undergone VDRO alone, and 24 had undergone VDRO and open reduction and/or pelvic osteotomy (with the decision to proceed with open hip reduction and/or pelvic osteotomy made intraoperatively based on fluoroscopy and arthrogram). Clinical variables, functional level, radiographic variables, and complications/revisions were compared between groups.

Results: Patients requiring combined surgery (VDRO+) had higher baseline migration percentages (MP) (84% ± 18 VDRO+, 51% ± 21 VDRO), higher acetabular indices (34 ± 10 VDRO+, 28 ± 7 VDRO), more negative center-edge angles (-36 ± 28 VDRO+, -0.3 ± 18 VDRO), and higher neck-shaft angles (162 ± 12 VDRO+, 157 ± 10 VDRO) (all P < 0.02). Postoperative radiographic variables were similar between groups. The percentage of patients with MP >30% at final follow-up was similar between groups (38% VDRO+, 33% VDRO). There were no differences in complications or revision rates between groups. Of the hips with MP >50% preoperatively and treated with VDRO alone, 41% developed postoperative MP of ≥ 30% and 21% developed a MP of ≥ 40%.

Conclusions: The study results confirm that combined procedures should be considered in patients with high MP. However, this study supports a sequential approach to surgical management of subluxated/dislocated hips in patients with CP as many hips with MP >50% were successfully managed with VDRO alone. We recommend performing VDRO and soft tissue release first, assessing reduction using fluoroscopy and arthrogram and proceeding with open reduction and/or pelvic osteotomy if reduction and/or femoral head coverage are inadequate.

Level of evidence: Level III, retrospective comparative study.