Impact of foot progression angle on spatiotemporal and plantar loading pattern in intoeing children during gait

Intoeing in children is a common parental concern, but our understanding of the impact of foot progression angle (FPA) in these children leaves remains limited. This study examines the relationship between FPA and plantar loading pattern, as well as gait symmetry in children with intoeing. The sample included 30 children with intoeing caused by internal tibial torsion, uniformly divided into three groups: unilateral intoeing, bilateral mild intoeing, and bilateral mild-moderate intoeing. The relationship between FPA and plantar loading pattern, and gait symmetry within and among groups were assessed using dynamic pedobarographic and spatiotemporal data. Results indicated a significant correlation between FPA and peak pressure, maximum force, and plantar impulse in the medial and central forefoot, and also the medial and lateral heel zones for both bilateral intoeing groups. Significant differences were observed only in subdivided stance phase, including loading response, single support, and pre-swing phases, between the unilateral intoeing and bilateral mild intoeing groups. These findings suggest that FPA significantly affects the forefoot and heel zones, potentially increasing the load on the support structures and leading to transverse arch deformation. While children with intoeing demonstrate a dynamic self-adjustment capability to maintain gait symmetry, this ability begins to falter as intoeing becomes more pronounced.