Evaluation of the effects on stride-to-stride variability and gait asymmetry in children with Cerebral Palsy wearing the WAKE-up ankle module

The main object of this study is to investigate the synergic interaction of the WAKE-up ankle-module with children with Cerebral Palsy, through the analysis of stride-to-stride variability and side-to-side asymmetry. The effects of the robotic assistance were evaluated by comparing gait patterns obtained during walking with and without the WAKE-up ankle-module on the more affected limb. The module provides 45° in plantarflexion and in dorsiflexion, at mid/forefoot strike and toe off, respectively. Gait phase percentages and spatio-temporal parameters of a cohort of three children with right hemiplegia were collected during five repetitions of two conditions: walking without device and walking wearing WAKE-up ankle-module. Kinematic data were also gathered from four age-matched healthy subjects during normal walking. Stride-to-stride variability was calculated using a coefficient of variation and gait asymmetry was computed with ratio index. Statistical differences in the first rocker percentage were observed in all patients; stride-to-stride variability decreased both in gait phase percentages and in spatio-temporal parameters for all patients. There were no statistical differences in gait asymmetry for all parameters for all patients with the exclusion of first rocker percentage relative to the second patient. Comparing the results of the patients with the ones gathered from the control group, the WAKE-up ankle-module demonstrates that it is potentially useful for the rehabilitation of gait patterns. Via the preliminary trials the ankle module allowed to recover physiological gait phase percentage and correct gait phase sequence, avoiding pathological events caused by equinus foot. Moreover, WAKE-up permitted the decrement in stride-to-stride variability and did not further alter the side-to-side asymmetry.