The medial longitudinal arch angle (LAA) of the foot has been used as an index of high and low arches. The LAA during the support phase of running (LAArun), which may be related to lower-limb injuries, is commonly predicted from the LAA at standing (LAAstand). However, it is not known whether this prediction is valid for all of the foot contact patterns. The purpose of this study was to verify whether prediction of the LAArun from the LAAstand is valid for different foot strike patterns.
The 26 participants were divided into a rearfoot strike group (n = 15) and a nonrearfoot strike group (n = 11). The LAA was obtained by measuring the angle formed between the line from the navicular bone to the medial malleolus and the line from the navicular bone to the first metatarsal head. The LAAstand and the minimum value of the LAArun, when the arch is most collapsed, were measured using a motion capture system.
There were no significant differences in the LAAstand, the LAArun, and the difference (LAAstand – LAArun) between the two groups. In both groups, a very strong and significant correlation was found between the LAAstand and the LAArun. Furthermore, a nearly identical equation for predicting the LAArun from the LAAstand was derived for the two groups.
The LAArun can be predicted from the LAAstand for any foot strike pattern with almost the same equation.