The effect of hinged ankle-foot orthosis on gait and energy expenditure in spastic hemiplegic cerebral palsy

Purpose. To assess the effectiveness of a hinged ankle-foot orthoses on gait impairments and energy expenditure in children with hemiplegic cerebral palsy (CP) whom orthoses were indicated to control equines. Method. Eleven children (seven males, four females) who had a diagnosis of hemiplegic cerebral palsy were included in the study. Each child underwent gait analysis and energy consumption studies with and without ankle-foot orthosis (AFO). The AFOs were all custom-made for the individual child and had plantarflexion stop at 0 degrees with no dorsoflexion stop. The Vicon 512 Motion analysis system was used for gait analysis. Walking energy expenditure measurements were done with breath by breath method using an open-circuit indirect calorimeter (Vmax 29c, Sensormedics, USA). All tests were carried out on the same day with enough resting period. Results. AFO application, as compared with the barefoot condition improved walking speed, stride length and single support time. Double support time was decreased significantly with AFOs and no change in cadance. Ankle dorsiflexion at initial contact, midstance and midswing showed significant increase. Knee flexion at initial contact was decreased and no significant change in maximum knee extension at stance and maximum knee flexion at swing was obtained. The oxygen consumption was significantly reduced during AFO walking. Conclusion. The hinged AFO is useful in controlling dynamic equinus deformity and reducing the energy expenditure of gait in children with hemiplegic spastic cerebral palsy.