Biomechanical changes in gait following selective dorsal rhizotomy

Object. The purpose of this study was to evaluate the effects of selective dorsal rhizotomy (SDR) on the walking pattern of children with cerebral palsy (CP). The authors hypothesized that SDR would reduce the overactive stretch reflex and result in improved joint positions, greater joint angular velocities and motion, and greater strides. The authors also expected that the changes from the SDR would be reflected in the electrical activities of the muscles. Methods. Twenty children with CP participated in the study. Ten underwent SDR and 10 who met the inclusion criteria but who did not undergo SDR formed a control group. Gait analysis was performed twice in both groups at comparable time intervals. Within-group (pre- and post-SDR) assessments and between-group (SDR compared with no SDR) assessments were performed. The results indicated that strides increased 1.4 cm on average (p < 0.001), hip and knee excursion increased as a result of greater hip and knee flexion in swing, and ankle dorsiflexion in stance improved. Hip-flexion and knee-extension velocities were increased in swing. Electromyography changes were consistent with these gait changes and support the authors' hypothesis. Conclusions. By attenuating the stretch response, SDR alters gait mechanics. The effects of SDR include greater strides, joint excursions, and joint angular velocity.