What has feet to do with it? Pes planus and medial arch height in adults with and without autism spectrum disorder

Individuals with autism have higher rates of minor physical anomalies (MPAs) than neurotypical persons. Minor physical anomalies are slight morphological deviations typically harmless and without cosmetic or medical importance to the individual but indicative of an underlying neurodevelopmental disorder. In genetic autism research the utilization of MPAs has been recommended. In the present study the prevalence of pes planus or flatfoot in adults with ASD compared to age and sex matched neurotypical adults was investigated with two different methods. A photograph of the feet was obtained from underneath while the subjects were standing on a glass table. From this imprint calculations were made. In addition the medial longitudinal foot arch was measured with a Verniper caliper. The ultimate purpose of this study was to evaluate if flatfoot deformity could be utilized as an MPA in ASD. In this cohort of nearly one hundred adults no one fulfilled the predefined criteria of a flatfoot diagnosis but a lower foot arch height was shown in individuals with ASD compared to controls, confirming the clinical impression.

► Strong support has been found for the association between minor physical anomalies (MPAs) and ASD.
► This study aimed to evaluate if flatfoot deformity could be utilized as an MPA in adults with ASD.
► Close to one hundred adults, with and without ASD, were investigated with two different methods.
► No one fulfilled the predefined criteria of a flatfoot diagnosis.
► Individuals with ASD displayed a lower foot arch height compared to controls.