Rectus femoris surgery in children with cerebral palsy. Part II: A comparison between the effect of transfer and release of the distal rectus femoris on knee motion.

Rectus femoris muscle (RF) surgery was performed in 98 children (136 sides) with cerebral palsy (CP). RF transfer was performed in 105 lower limbs, and distal RF release was performed in 31. Eleven (20 sides) similarly affected children had no RF procedure and are included for comparison. Gait analysis was performed just before and approximately 1 year after surgery. All children underwent other orthopaedic surgery at the time of the RF procedure. When preoperative knee range of motion (ROM) was > 80% of normal, there were no significant changes in knee motion in either the RF transfer or distal release groups. In patients with < 80% of normal knee ROM preoperatively, RF transfer was followed by maintained knee flexion in swing; patients who underwent distal RF release or no RF procedure showed a decrease (10 degrees and 6 degrees, respectively) in knee flexion postoperatively. These results suggest that the RF should be transferred and not released when knee ROM is < 80%.