Radical Posterior Capsulectomy Improves Sagittal Knee Motion in Crouch Gait

Abstract

Knee flexion contracture leading to crouch gait is commonly seen in children with myelomeningocele. Progressive increase in knee flexion contracture increases energy cost, which interferes with efficient, functional ambulation. To prevent this, surgical release has been recommended when a knee flexion contracture exceeds 15° to 20°. We therefore asked whether knee flexion contracture release improved dynamic sagittal motion and walking velocity using computerized gait analysis. We retrospectively studied 11 patients (20 knees) with high-sacral-level or low-lumbar-level myelomeningocele and knee flexion contracture of greater than 15°. All patients underwent dynamic gait analysis pre- and postoperatively. Surgery consisted of selective hamstring lengthening (medial and lateral), gastrocnemius release from the femoral condyles, and posterior knee capsulectomy. We observed improvements postoperatively in clinical measurements and sagittal kinematics. The clinical knee flexion contracture improved from a mean of 24.9° preoperatively to 5.9° postoperatively. The knee flexion at initial contact improved from 37.6° to 9.0°, and minimum knee flexion in single-leg stance improved from 48.2° to 16.4. Walking velocity improved from 72.2% to 80.0% of age-matched normal. Surgical treatment of knee flexion contracture in patients with myelomeningocele using radical posterior knee capsulectomy leads to improvement in clinical knee flexion contracture, dynamic sagittal kinematics, and walking velocity.