Move more, learn better: Contribution of sway variability to achieving sitting milestone in infants with Cerebral Palsy

Movement experiences foster infants’ motor development. After experiencing self-induced optical flow, crawlers learned to attune their posture in response to the visual change of the situated environment. Experiences of self-induced motion are essential to master advanced motor skills. However, children with Cerebral Palsy (CP) have difficulty controlling their body segments, which delays the mastering motor skills (i.e., sitting). In this study, we sought to examine whether movement patterns in early sitting behavior would be associated with the achievement of independent sitting. .Twenty-five infants with moderate to severe CP received physical therapy two hours/week for 3 months after enrollment. All infants could prop-sit for 10s when entered the study. Sitting postural sway data was recorded with a force platform within one week of onset of first prop-sitting. Center-ofPressure data collected from forceplate was analyzed. Children’s achievement of sitting posture as sitting stage was coded 3 months after onset of first sitting. Three-months after the first prop-sitting onset, 12 out of 25 infants progressed to independent sitters. Repeated-measure ANOVA showed that RMS and range in the antero-posterior direction, as prop sitting first onset, were significantly higher in children with CP who progressed in sitting stage than those who remained in the prop sitting stage. As beginning sitters, infants with CP couldn’t efficiently utilize postural movement to explore the environment. Greater movement experience (higher sway variability) is associated with the progress of independent sitting, suggesting that activities facilitate greater movement during sitting may be beneficial for infant with CP in developing sitting skill