Gait Analysis Outcomes of Percutaneous Medial Hamstring Tenotomies in Children With Cerebral Palsy

Background: Hamstring lengthening procedures are commonly performed on children with cerebral palsy (CP) to improve gait. The purpose of this study was to determine the efficacy of percutaneous hamstring tenotomy surgery for children with ambulatory CP. Methods: In this retrospective study, subjects were included if they had a diagnosis of CP and had computerized gait analysis data collected before and after surgery. Subjects were not included in the study if they had any open hamstring lengthening on the same side. Other concomitant lower extremity surgeries were not exclusionary. Short- and long-term follow-up groups were established: if the time from their surgery to their gait laboratory was less than 18 months, they were placed in the short-term follow-up group, and if the time from their surgery to their gait laboratory was greater than 18 months, they were placed in the long-term follow-up group. Results: The results demonstrated that for short- and long-term groups on preoperative to postoperative analysis, there was significantly improved knee extension at initial contact, increased velocity, increased stride length, improved overall gait as indicated by a decrease in a 16 variable multivariate index (Gillette Gait Index), and a decreased popliteal angle. For the short-term group only, additional significant findings included increased peak knee extension in stance and reduced plantar flexion at initial contact. The absolute values of peak knee extension in stance and plantar flexion at initial contact were equivalent at follow-up for the short- and long-term groups. Increased anterior pelvic tilt was also significant for the short- term follow-up group only. Conclusions: The findings of this study demonstrate that the minimally invasive technique of percutaneous hamstring tenotomy is effective in improving key dynamic gait parameters for individuals with CP for a short period, and these benefits are maintained in the long term. Level of Evidence: Level IV.