Dynamic function of the human fibula

Abstract

Abstract There is general agreement that motion between the tibia and fibula is an important and necessary part of normal ankle function in man. We studied the function of the tibiofibular unit in healthy college athletes running barefooted. Movies and cine‐roentgenograms showed the fibula moving downward and laterally during the strike phase of gait. Fibular motion in this direction rather than upward, as suggested by cadaver studies, deepens the ankle mortice and stabilizes the joint when the ankle is dorsiflexed and load is the greatest. This motion also stretches the interosseous membrane and tibiofibular ligaments, converting compressive force in the ankle to tension in these structures.