Differences in the dynamic gait stability of children with cerebral palsy and typically developing children.

The aim of this investigation was to evaluate the differences in the dynamic gait stability of children with cerebral palsy (CP) and typically developing (TD) children. The participants walked on a treadmill for 2 min as a motion capture system assessed the walking kinematics. Floquet analysis was used to quantify the rate of dissipation of disturbances that were present in the walking kinematics, and the variability measures were used to assess the magnitude of the disturbances present in the step length and width. The Floquet multipliers, step width and length values were correlated with Sections D and E of the Gross Motor Function Measure (GMFM). The children with CP had a larger Floquet multiplier and used a wider step width than the TD children. The magnitude of the maximum Floquet multiplier was positively correlated with the step width. Furthermore, the magnitude of the maximum Floquet multiplier and the step width were negatively correlated with the score on Section E of the GMFM. Lastly, the children with CP used a more variable step length than the TD children. These results suggest that children with CP have poor dynamic gait stability because they require more strides to dissipate the disturbances that are present in their walking pattern. In effort to stabilize these disturbances, the children with CP appear to utilize a wider step width and modulate their step length. Overall the inability to effectively dissipate the gait disturbances may be correlated with the child's ability to perform a wide range of gross motor skills (e.g., step over obstacles, jump, walk up stairs).