Hip Development after Selective Dorsal Rhizotomy in Patients with Cerebral Palsy

Objective The effects of selective dorsal rhizotomy (SDR) on the hip development in children with spastic cerebral palsy (CP) are not well defined. The present study was performed to determine the effects of SDR and other associated clinical and radiological factors on the outcome of hip development after SDR. Methods The study included 53 patients who were skeletally immature at the time of SDR. Between 2003 and 2010, they underwent SDR at our institute. The age ranged from 4 to 15 years old. Their preoperative hip status was divided into two groups: normal and abnormal. The final outcome of the hip was considered good if the centre-edge angle of Wiberg (CEA) at last follow-up was more than 20 degrees without the need for orthopaedic intervention. Thirty-seven patients satisfied the inclusion criteria for statistical analysis. Results Seventeen patients were in the “Normal pre-op” group. In all patients (except for two patients), the hip status remained normal after the SDR. Twenty patients were in the “Abnormal pre-op” group. In this group, only two patients returned to normal hips, whereas 11 patients required orthopaedic hip surgery within 5 years after the SDR. The remaining seven patients had hip subluxation, but not to the extent of hip dislocation. The preoperative hip radiological measurements and functional status were positively correlated with the postoperative hip status. The preoperative radiological measurements showed superior predictive value when other covariance were considered. No difference of outcome existed in regard to the different surgical approaches of SDR. Conclusion Selective dorsal rhizotomy has a neutral effect on hip development. The preoperative hip radiological measurement is the most important predictive factor to determine hip status after SDR. Good collaboration between neurosurgeons and paediatric orthopaedists is essential for the best management of these patients.