Children with cerebral palsy effectively modulate postural control to perform a supra-postural task.

The purpose of this study was to determine whether signatures of adaptive postural control remain present in children with cerebral palsy (CP) when they performed a supra-postural task (i.e., a task performed above and beyond the control of posture) requiring them to balance a marble inside a tube held in the hands. Measures of center of pressure (COP) dynamics (how regular or predictable were the COP data as quantified by the sample entropy metric) and variability (as quantified by the COP standard deviation) were obtained from a sample of children with CP (n=30) and compared to the same measures taken from typically developing (TD) children. Children with CP demonstrated an apparent inefficiency in postural control (greater irregularity, greater sway variability) relative to TD peers during a quiet-stance (no supra-postural task) condition (p<.05). During supra-postural task performance, those differences were attenuated, though they remained statistically different (p<.05). The findings illustrate flexibility and adaptability in the postural control system, despite the pathological features associated with CP.