Iliopsoas tenotomy at the lesser trochanter versus at the pelvic brim in ambulatory children with cerebral palsy

BACKGROUND:: Progressive hip flexion deformity is a common problem in ambulatory children with spastic cerebral palsy, causing static and dynamic deformity. The iliopsoas muscle is recognized as a major deforming force in the development of this problem. Many clinicians address this problem by lengthening the iliopsoas, either in an intramuscular location at the pelvic brim or by complete tenotomy at the lesser trochanter. The goal of this study was to compare the outcomes of patients with ambulatory cerebral palsy who had intramuscular lengthening at the pelvic brim to those who underwent complete release of the iliopsoas tendon at the level of the lesser trochanter. METHODS:: Twenty patients were included in the study, 11 of whom had iliopsoas release at the lesser trochanter (group 1) and 9 of whom had intramuscular lengthening at the pelvic brim (group 2). All patients had physical examinations, plus kinematic and kinetic analyses in our gait laboratory before and 1 year after surgery. RESULTS:: Hip flexion contracture was decreased significantly only in group 1, although there was a trend of decrease in group 2. There was a significant increase in maximum hip extension in terminal stance and a reciprocal decrease in maximum swing phase hip flexion ingroup 1, with a similar trend that did not reach significance in group2. Stride length increased significantly in both groups. There was no significant change in power generation of hip flexion during the swing phase in either group. CONCLUSIONS:: We found improved static and dynamic parameters of hip extension after iliopsoas lengthening and did not detect any adverse kinematic or kinetic change in hip function after surgery. The improvement was more robust in the group who underwent release at the lesser trochanter. Because there are no adverse effects of iliopsoas release from the lesser trochanter and the improvement in hip extension is greater, this approach should be considered in ambulatory patients with spastic diplegia when a hip flexor weakening procedure is considered.