Abnormal Gait Patterns in Autism Spectrum Disorder and Their Correlations with Social Impairments

Ground walking in humans is typically stable, symmetrical, characterized by smooth heel-to-toe ground contact. Previous studies on children with autism spectrum disorder (ASD) identified various gait abnormalities. However, they produced inconsistent findings, particularly for the occurrence of toe walking and gait symmetry between feet, owing to their reliance on retrospective reports, visual analysis of videos, or kinematic analysis of the gait. The present study examined gait functions in children with ASD using plantar pressure that quantified foot-ground interaction with high spatial and temporal resolutions. Fifty-eight 4-6-year-old children with ASD (12 low-functioning and 46 high-functioning autism) and 28 age-matched typically developed children walked straight 6 m at their preferred speed for 10 repetitions. We found that both ASD groups walked with more flat-footed contact pattern, more left-right asymmetry, and larger step-to-step variability than their controls. Furthermore, these abnormal gait characteristics were related to social impairments measured by the Autism Spectrum Quotient and Social Responsive Scale, supporting a close association between impaired motor coordination and core symptoms of autism. Lay Summary We examined gait functions among children with autism by measuring their foot plantar pressure during simple straight walking. Children with ASD walked with a characteristic foot-ground contact pattern with inappropriate contact forces and large step-to-step variability when compared with their age-matched controls. These walking abnormalities were dependent on their social impairments but independent from their intelligence, indicating a close relationship between atypical motor coordination and core symptoms of autism.