A Multimodal Analysis of Foot Asymmetry: Associations with Handedness and Sex Using Podoscopic and Anthropometric Analysis

This study aimed to investigate whether foot asymmetry is influenced by handedness and sex, using detailed podoscopic and anthropometric assessments. Because lateralised behaviours are known to affect upper-limb morphology, this research sought to determine whether similar patterns occur in the feet, particularly in relation to structural measurements and plantar support distribution. Plantar images of 297 adults were obtained using a validated podoscope system under 50% and 90% body-weight conditions. Foot length, width, and plantar area were quantified, and asymmetry indices (R–L) were calculated. Handedness was determined using the Edinburgh Handedness Inventory. Sex- and handedness-related differences were analyzed using independent-samples t-tests. Right-handed individuals demonstrated significantly larger plantar areas on the right foot at 50% body-weight loading and on the left foot at 50% and 90% loading when compared with left-handed participants (p < 0.05). However, asymmetry index values for foot length, width, and area did not differ significantly between handedness groups or between males and females under either loading condition (p > 0.05). These findings indicate that minor absolute differences in plantar area do not translate into meaningful directional asymmetry. Foot structural asymmetry does not appear to be influenced by handedness or sex. Despite slight variations in plantar area loading patterns, overall asymmetry indices remained consistent across all groups, suggesting that lower-limb morphology is largely independent of lateralisation preferences.