Influence of Foot Morphology on Postural Sway During Childhood

Postural control matures during childhood alongside the musculoskeletal system, though development is often asynchronous and influenced by sex. In this process, foot morphology is especially relevant, as the plantar surface provides key somatosensory input to the central nervous system. However, the role of foot-ground interaction in balance regulation remains largely unexplored. In this study, we attempted to clarify the association between foot morphology-measured via footprint-based indices-and static balance through postural sway analysis.

Using a pressure platform, we simultaneously collected data on center of pressure (COP) trajectories during quiet upright stance and plantar pressure distribution in a sample of 178 children aged 6-11. Raw data were processed to calculate sway area and COP path length, as well as the Arch Index, which was used to categorize foot morphology as cavus, normal, or flat.

Among girls aged 8-9 years, statistically significant differences in postural sway parameters were observed across foot morphology groups, with individuals presenting cavus feet exhibiting greater sway area and COP path length values. A comparable tendency was also identified in those aged 10-11. In contrast, boys aged 10-11 with flat feet displayed lower sway area values under the eyes-closed condition and reduced COP path length under the eyes-open condition compared with peers presenting normal or cavus foot morphology.

Overall, these findings suggest that postural control during childhood is influenced by the mechanical and sensory characteristics of the foot-ground interface, and that sex represents a relevant moderating factor in this relationship.