The purpose of this study was to determine the efficacy of the proximal rectus femoris release to treat hip flexor contractures and hip and pelvic gait deviations in children with spastic cerebral palsy. This study was a retrospective repeated-measures analysis of data collected on two matched groups of patients, those with and without proximal rectus femoris release surgery, seen in our Motion Analysis Laboratory. Proximal rectus release surgery did not improve hip extension, did not decrease anterior pelvic tilt, and did not improve temporal-distance measures of gait in children with cerebral palsy. A multivariate measure, the Hip Flexor Index, was also unchanged. The group of patients without any hip flexor surgery was not different from the rectus femoris release group on hip or pelvic variables before or after surgery. The findings of this study offer no evidence that the proximal rectus femoris release is successful in achieving desired gait outcomes at the hip and pelvis in children with cerebral palsy.