O 003 – Radiographic predictors of foot function during walking in pediatric foot deformities

Abstract

Children with Down syndrome (DS) are known for their reduced balance control, and typically take longer to develop motor skills and display less coordinated movement patterns. Hopping in-place is a gross motor skill requiring whole-body vertical stiffness and horizontal movement control, particularly when attempting to modify hopping frequency. However, there is a lack of knowledge of the hopping capacity of children with DS.The purpose of this study was to assess the ability of children with DS aged 5–11 years old to continuously hop in-place on two legs and compare their biomechanical patterns to those of typically developing (TD) children.This observational study included 14 children with DS and 16 TD children. Subjects were asked to complete 20 s trials of two-legged hopping in-place at a self-selected frequency, and four metronome guided conditions: preferred (self-selected frequency), moderate (20% increase), fast (40% increase) and slow (20% decrease). Two sample independent t-tests were conducted on whole-body vertical stiffness, horizontal center-of-mass movement, and toe displacement between hops for the self-selected hopping condition and two-way ANOVAs were used for the metronome conditions.Our findings suggest that children with DS might not be able to continuously hop in-place until the age of 7 years old, and were unable to hop for as long in duration as their TD peers. Children with DS self-selected a faster hopping frequency, and demonstrated an increased medial-lateral center-of-mass movement during the stance phase of hopping, suggesting reduced balance control. Moreover, children with DS were unable to correctly modify their hopping frequency when cued by a metronome and exhibited an inability to modulate whole-body vertical stiffness and constrain horizontal or vertical movement. These results demonstrate the utility of a future hopping intervention to improve whole-body vertical stiffness and balance control in children with DS.