Article Changes in Sagittal Plane Kinematics and Kinetics after Distal Release of Medial Hamstrings in Cerebral Palsy

Abstract: The purpose of this study is to analyze the effect of distal release of the medial hamstrings on the gait of patients who had spastic cerebral palsy. Twenty-two patients had preoperative and postoperative gait analysis. Standard parameters, such as cadence, velocity, and stride length, were evaluated, as were sagittal plane motion graphs of the pelvis, hip, knee, and ankle, in addition to sagittal plane kinetic analysis. Extension of the knee in stance phase significantly improved postoperatively (p < 0.002), and the improvement was accompanied by a proportional decrease in knee flexion during swing with minimal net gain in the arc of knee motion. Knee range of motion could be improved more by concomitant rectus transfer in selected patients. The statistically significant increase in anterior pelvic tilt (p < 0.002) has been a main concern. There was no significant change in the hip extensor moments or power generation during stance. Increased knee extension during stance after distal release of medial hamstrings is the kinematic gain that improved the gait pattern in cerebral palsy patients. The authors recommend a concomitant rectus transfer to help improve the knee range of motion in patients with rectus over-firing during swing, hence avoiding a stiff knee gait