2025 Volume 3 Issue 1 Pages 22-30
Objective: The purpose of this study was to examine the effects of flatfoot type and knee joint flexion angle on lower limb alignment during static standing.
Methods: Twenty-three healthy young adult males with flatfoot were classified into 13 flexible types and 10 rigid types using Arch Height Flexibility, a measure of foot arch flexibility. The task was a double-leg static standing with different knee flexion angles (0°, 25°, 50°) on wedges (0°, 20°). For the angles of knee varus/valgus and internal/external rotation, and hip adduction/abduction and internal/external rotation, the value obtained by subtracting the joint angle at 0° from 20° on the wedges was calculated as the amount of change and compared among the types.
Results: There was no interaction between flatfoot type and knee joint flexion angle condition, nor was there a main effect between flatfoot types for all analysis items (p ＞0.05). A main effect was found between knee flexion angle conditions for knee joint varus/valgus, internal/external rotation, and hip joint adduction/abduction (p ＜0.05).
Conclusion: This study revealed that the type of flatfoot had no effect on the lower limb alignment during static standing, but the difference in knee joint flexion angle affected the lower limb alignment during static standing.
