Long-term Effects of Femoral Derotation Osteotomies: an Evaluation Using Three-dimensional Gait Analysis

The purpose of this study was to evaluate the long-term effects of the femoral derotation osteotomy (FDO) in the ambulatory patient with cerebral palsy (CP). The effectiveness of the FDOs were evaluated using three-dimensional gait analysis just before surgery (P0), 1 year after surgery (P1), and 5 years after surgery (P2). A total of 20 patients (27 sides) with CP were evaluated. Related physical examination and motion measures showed significant improvements at P1 that were maintained at P2. Mean maximum internal hip rotation at P0 of 77 degrees +/- 9 degrees decreased to 53 degrees +/- 8 degrees at P1 and was maintained at 58 degrees +/- 11 degrees at P2. Mean maximum external hip rotation at P0 of 21 degrees +/- 11 degrees increased to 35 degrees +/- 15 degrees at P1 and was maintained at 32 degrees +/- 13 degrees at P2. Mean femoral anteversion at P0 of 63 degrees +/- 9 degrees was reduced to 26 degrees +/- 15 degrees and was maintained at 31 degrees +/- 13 degrees at P2. During gait, mean hip rotation in stance at P0 of 20 degrees +/- 8 degrees was decreased to 2 degrees +/- 10 degrees at P1 and was maintained at 4 degrees +/- 5 degrees at P2. There were associated significant foot progression changes from an internal progression mean of 5 degrees +/- 17 degrees at P0 to -11 degrees +/- 17 degrees at P1 that were maintained at -12 degrees +/- 5 degrees at P2. The findings suggest that the FDO is a viable and lasting treatment option for the correction of anteversion and associated internal hip rotation during gait in children with CP.