Relationships of three arch height indices related to different foot lengths between sitting and standing postures

Abstract

Arch height index (AHI) between sitting and standing is an important reference in assessing foot mobility and foot classification in podiatry clinic. The relationships of three types of AHIs related to different foot lengths in sitting and standing postures are desired to be investigated in clinical applications. The purpose of this study is to investigate the relationships of three arch height indices (AHIs) calculated from total foot length, medial ball length and lateral ball length between sitting and standing postures and to examine the performances of them. Three AHIs of right feet of 150 subjects, including 83 males and 67 females, were measured using 3D foot scanner with an accuracy level of 0.05 cm in sitting and standing postures in this study. The results showed that three AHIs were significantly different from each other, and had the same performances between sitting and standing postures. AHI values in the sitting posture were all larger than those in the standing posture, and AHI-MBL has a better explaining power on AHI-TFL than AHI-LBL on AHI-TFL in both postures. The time and priority of using these three AHIs in evaluating foot types with normality and deformity were suggested.