Examining the specificity of postural control deficits in children with Autism Spectrum Disorder using a cross-syndrome approach

Background: Postural control deficits are commonly reported in children with Autism Spectrum Disorder (ASD). However, identification of specific postural sway features that differentiate ASD from other neurodevelopmental disorders has not been examined. The current study employs a cross-syndrome approach by comparing postural sway area and direction-specific features of sway magnitude, sway velocity, and sway complexity between children with ASD, Fetal Alcohol Spectrum Disorder (FASD), Attention-Deficit Hyperactivity Disorder (ADHD), and typically developing (TD) controls. Method: Eighty children (7–17 years old) participated in this study. Postural sway was measured on a force plate during 30-s of bilateral quiet stance and balance was assessed using a timed unipedal stance test. Results: Results showed that (1) postural sway area and mediolateral (ML) sway magnitude were significantly greater in children with ASD vs. all groups (p < 0.05); (2) anteroposterior (AP) sway magnitude and velocity were significantly greater in children with ASD vs. TD controls-only (p < 0.05); and (3) static balance was similarly impaired in all clinical groups compared to TD children (p < 0.05). Conclusions: ASD-specific postural sway features were identified using a cross-syndrome design. Identifying ASD-specific motor impairments can be useful to understanding the neurological underpinnings of ASD.