Long-term changes in femoral anteversion and hip rotation following femoral derotational osteotomy in children with cerebral palsy

•Novel comparison of long-term gait, anteversion after an FDO versus a control group.•FDO group had less anteversion than the control group at long-term.•FDO and control groups had similar hip rotation in stance at long-term.•Over one-third of hips remained excessively internal in both groups at long-term.•Recurrence of internal hip rotation was 12% in the FDO group at long-term.

BackgroundExcessive femoral anteversion is common in cerebral palsy (CP), is often associated with internal hip rotation during gait, and is frequently treated with a femoral derotational osteotomy (FDO). Concerns exist regarding long-term maintenance of surgical outcomes. Past studies report varying rates of recurrence, but none have employed a control group.MethodsWe conducted a retrospective analysis examining long-term (∼5 years) changes in anteversion and hip rotation following FDO in children with CP. We included a control group that was matched for age and exhibited excessive anteversion (>30°) but did not undergo an FDO. Anteversion, mean stance hip rotation, and rates of problematic remodeling and recurrence were assessed (>15° change and final level outside of normal limits).ResultsThe control group was reasonably well matched, but exhibited 9° less anteversion and 3° less internal hip rotation at the pre time point. At a five year follow-up, the FDO group had less anteversion than the control group (20° vs. 35°, p < 0.05). The mean stance phase hip rotation did not differ between the groups (4° vs. 5°, p = 0.17). Over one third of limbs remained excessively internal in both groups (FDO: 34%, Control: 37%). Rates of problematic recurrence and remodeling were low (0%-11%).ConclusionsAn FDO is an effective way to correct anteversion in children with CP. Long-term hip rotation is not fully corrected by the procedure, and is not superior to a reasonably well matched control group. Rates of problematic recurrence and remodeling are low, and do not differ between the groups.