The difference of foot pressure distribution on one-leg standing at the four leaning positions in anteroposterior direction

Abstract

  The functional roles of six foot sole regions were examined during one-legged standing in four center-of-foot pressure (CFP) positions in the anteroposterior direction. These positions were determined according to the distance of the CFP from the heel in relation to total foot length (%FL). Fifteen participants maintained the one-legged standing positions at 30%FL, 45%FL, 60%FL, and 70%FL for 12 seconds. In the 30%FL and 45%FL positions, the pressure values were higher in the heel and the lateral sole than in the medial forefoot. Negative correlations were observed between the pressure variation in the lateral forefoot_and medial forefoot, and between the mid foot and medial forefoot. Pressure variation in the medial forefoot and peroneus longus muscle activity was correlated, as was pressure variation in the medial forefoot and abductor pollicis muscle activity. In the 60%FL and 70%FL positions, the forefoot region had the greatest pressure. There was a negative correlation between medial forefoot and lateral forefoot pressure variation. There was a significant correlation between the pressure variation in the medial forefoot and peroneus longus muscle activity. This suggests that the lateral sole in the 30%FL and the 45%FL positions and the forefoot in the 60%FL and 70%FL positions played the role of the fulcrum for weight bearing. In addition, it is likely that the medial forefoot in the 30%FL and the 45%FL positions, and the medial forefoot and the lateral forefoot in the 60%FL and the 70%FL positions play important roles of the point of application for postural control.