Banks Jacob J, Chang Wen-Ruey, Xu Xu, Chang Chien-Chi
Liberty Mutual Research Institute for Safety, Center for Physical Ergonomics, 71 Frankland Road, Hopkinton, MA 01748, USA.
Department of Industrial Engineering and Engineering Management, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC.
Gait Posture. 2015 Jun;42(1):101-3. doi: 10.1016/j.gaitpost.2015.03.015. Epub 2015 Mar 30.
Heel strike instants are an important component of gait analyses, yet accurate detection can be difficult without a force plate. This paper presents two novel techniques for kinematic heel strike instant (kHSI) detection which examined maximal resultant horizontal heel displacement (HHD). Each of these HHD techniques calculates HHD from a selected reference location of either the stance ankle or stance heel to the swing heel. The proposed techniques, along with other previously established techniques, were validated against a 10N force plate threshold. Fifty-four healthy adults walked overground at both normal and fast speeds while wearing athletic shoes. The reported true and absolute errors were as low as 3.2 (4.4) and 5.7 (3.4)ms, respectively, across 8678kHSI when using the stance ankle as a reference, which significantly outperformed (p<0.0001) the established techniques. Gait speed was shown to have a significant effect (p<0.0001) on HHD-determined kHSI, as well as the three other techniques evaluated, highlighting the need for condition-specific identification of kHSI.
足跟触地瞬间是步态分析的一个重要组成部分，然而，没有测力板的情况下准确检测可能会很困难。本文提出了两种用于运动学足跟触地瞬间（kHSI）检测的新技术，该技术检测了足跟最大水平合力位移（HHD）。这些HHD技术中的每一种都是从站立脚踝或站立足跟的选定参考位置到摆动足跟来计算HHD。所提出的技术以及其他先前建立的技术，通过10N测力板阈值进行了验证。54名健康成年人穿着运动鞋以正常和快速两种速度在地面行走。当以站立脚踝为参考时，在8678次kHSI中，报告的真实误差和绝对误差分别低至3.2（4.4）和5.7（3.4）毫秒，这显著优于（p<0.0001）已建立的技术。研究表明，步态速度对基于HHD确定的kHSI以及评估的其他三种技术都有显著影响（p<0.0001），这突出了针对特定条件识别kHSI的必要性。
