Foot Progression Angle Modulates Knee Loading During Walking in Individuals with Flexible Flatfoot
摘要
This study evaluated tibiofemoral loading and medial meniscal stress distribution in individuals with flexible flatfoot (FFF) during walking under different foot progression angle (FPA) conditions.
MethodsThis study analyzed the gait of 28 FFF patients (16 males, 12 females) under three FPA conditions (neutral, toe-in, toe-out). Kinematic (Vicon) and kinetic (Kistler) data were used to estimate tibiofemoral forces in OpenSim. Subsequently, joint angles and muscle forces at peak tibiofemoral forces were used to drive a finite element (FE) model of the knee, enabling the comparison of meniscal von Mises stress, maximum shear stress, and contact pressure across FPA conditions.
ResultsTibiofemoral force increased during early stance (9–11%) in the toe-in condition with this increase reaching statistical significance in males (p = 0.008, mean partial
Adjusting FPA modulates intra-articular knee loading via the kinetic chain. For FFF patients, neutral FPA provides stable loading. The toe-in condition presents a complex mechanism: despite increasing tibiofemoral force (notably in males), it reduces peak stress by altering contact mechanics and stress distribution. Therefore, FFF gait interventions must be individualized based on factors like foot morphology, sex, and functional goals.