Aim: To evaluate the effectiveness of distal rectus femoris (RF) release versus transfer to treat gait abnormalities of the knee in ambulatory children with cerebral palsy.

Patients & Methods: Thirty-nine children were included in this study. Thirty patients (55 limbs) underwent RF transfer at a mean age of 11.8 years. and nine (16 limbs) underwent distal rectus release at a mean age of 12.5 years. Indications for surgery included RF contracture and abnormal activity during swing phase in dynamic electromyography (EMG), whether with the presence of kinematic characteristics of stiff-knee gait or not. All patients had pre- and postoperative gait analysis and EMG. To evaluate functional outcomes, patients were grouped by pre-operative knee kinematics (normal; swing-phase peak knee flexion (PKF) < 50°; and peak knee flexion > 50° happening later than 77% of the cycle). All data was analyzed statistically.

Results: For the group of patients with PNF< 50°, this value increased significantly after rectus transfer (p=.005). Children with PNF> 50° and later than 77% of the cycle, showed significant improvement in timing after both procedures (p=.001; p=.02). When kinematic parameters were normal before surgery, they did not improved, although patients experienced a significant decrease of muscle contractures.

Conclusions: According to the results of this study, RF transfer would be the preferred procedure for those patients with preoperative swing-phase knee flexion < 50°. For the rest of patients, both procedures brought similar results. We opt for distal RF release since is technically easier, particularly when one-stage multilevel procedures are being performed.