Natural gaits of the non-pathological flat foot and high-arched foot.

Yifang Fan,Changsheng Lv,Donglin Luo,Yubo Fan,Zhiyu Li,Adrian Thomas

doi:10.1371/journal.pone.0017749

Abstract

There has been a controversy as to whether or not the non-pathological flat foot and high-arched foot have an effect on human walking activities. The 3D foot scanning system was employed to obtain static footprints from subjects adopting a half-weight-bearing stance. Based upon their footprints, the subjects were divided into two groups: the flat-footed and the high-arched. The plantar pressure measurement system was used to measure and record the subjects' successive natural gaits. Two indices were proposed: distribution of vertical ground reaction force (VGRF) of plantar and the rate of change of footprint areas. Using these two indices to compare the natural gaits of the two subject groups, we found that (1) in stance phase, there is a significant difference (p<0.01) in the distributions of VGRF of plantar; (2) in a stride cycle, there is also a significant difference (p<0.01) in the rate of change of footprint area. Our analysis suggests that when walking, the VGRF of the plantar brings greater muscle tension to the flat-footed while a smaller rate of change of footprint area brings greater stability to the high-arched.

Highlights

Foot arches are the result of the successive evolution of basic human activities such as walking [1,2,3]
What difference exists in the gaits of people with the non-pathological flat foot and high-arched foot? Will this difference exert an effect upon walking? If so, how? As yet no satisfactory answers have been provided to these questions
We examined the prospective subjects with help from the Orthopedics Department of our clinic to screen and exclude subjects with pathological flat foot or higharched foot symptoms such as Talipes calcaneovalgus, Congenital talipes equinovarus (CTEV), or planter flexion anomaly

Summary

Introduction

Foot arches are the result of the successive evolution of basic human activities such as walking [1,2,3]. The usual methods to collect the foot arch shape include footprinting, X-ray, plantar pressure measurement, laser scanning measurement and MRI scanning [8,9,10,11,12]. Using indices such as the footprint ratio and foot arch index, we can divide the foot shape into three categories: normal, high-arched and flat. Others indicate that the flat foot exerts effects on velocity, stamina and/or balance [15,16] while those possessing the high-arched foot are unsuitable sprint athletes [17]. What difference exists in the gaits of people with the non-pathological flat foot and high-arched foot? What difference exists in the gaits of people with the non-pathological flat foot and high-arched foot? Will this difference exert an effect upon walking? If so, how? As yet no satisfactory answers have been provided to these questions

Methods

Results

Conclusion