Gait adaptation of children with cerebral palsy compared with control children when stepping over an obstacle.

This study investigated the adaptive gait pattern in obstacle clearance in 12 normally developing (ND) children (six males, six females; mean age 10y 2mo, SD 10mo) and 12 children who had spastic diplegic cerebral palsy (CP) and who were independent ambulators (10 males, two females; mean age 13y 5mo, SD 2y 7mo). Children in both groups had 8 to 12 years of walking experience. They walked up to and crossed over obstacles of a height of 0%, 10%, and 20% of their leg length. Kinematic aspects of the three-dimensional leg movements were captured with the Vicon system and analyzed with one-way analysis of variance with repeated measure. Both groups increased foot clearance for higher obstacles. Children with CP were slower in approach and crossing speed, and used a wider base of support than the ND children when the obstacle height was increased. Results suggest that motor problems in obstacle clearance in children with CP lie in the implicit process of motor control, i.e. torque dynamics, not the explicit process, i.e. movement-match with the environmental constraints.