Laboratory of Movement Analysis and Measurements, Ecole Polytechnique Fédérale de Lausanne,-STI-IBI2-LMAM, Station 11/ELH 137, CH-1015 Lausanne, Switzerland.
J Biomech. 2010 Nov 16;43(15):2999-3006. doi: 10.1016/j.jbiomech.2010.07.003. Epub 2010 Jul 24.
This study describes the validation of a new wearable system for assessment of 3D spatial parameters of gait. The new method is based on the detection of temporal parameters, coupled to optimized fusion and de-drifted integration of inertial signals. Composed of two wirelesses inertial modules attached on feet, the system provides stride length, stride velocity, foot clearance, and turning angle parameters at each gait cycle, based on the computation of 3D foot kinematics. Accuracy and precision of the proposed system were compared to an optical motion capture system as reference. Its repeatability across measurements (test-retest reliability) was also evaluated. Measurements were performed in 10 young (mean age 26.1±2.8 years) and 10 elderly volunteers (mean age 71.6±4.6 years) who were asked to perform U-shaped and 8-shaped walking trials, and then a 6-min walking test (6MWT). A total of 974 gait cycles were used to compare gait parameters with the reference system. Mean accuracy±precision was 1.5±6.8cm for stride length, 1.4±5.6cm/s for stride velocity, 1.9±2.0cm for foot clearance, and 1.6±6.1° for turning angle. Difference in gait performance was observed between young and elderly volunteers during the 6MWT particularly in foot clearance. The proposed method allows to analyze various aspects of gait, including turns, gait initiation and termination, or inter-cycle variability. The system is lightweight, easy to wear and use, and suitable for clinical application requiring objective evaluation of gait outside of the lab environment.
本研究描述了一种新的可穿戴系统，用于评估三维空间步态参数。新方法基于时间参数的检测，结合优化的融合和惯性信号的去漂移积分。该系统由两个无线惯性模块附着在脚上组成，根据三维足运动学的计算，提供步长、步速、足离地间隙和转弯角度参数。与参考的光学运动捕捉系统相比，评估了该系统的准确性和精度。还评估了其在多次测量中的可重复性（测试-重测可靠性）。在 10 名年轻（平均年龄 26.1±2.8 岁）和 10 名老年志愿者（平均年龄 71.6±4.6 岁）中进行了测量，要求他们进行 U 形和 8 字形行走试验，然后进行 6 分钟步行试验（6MWT）。总共使用了 974 个步态周期来比较参考系统的步态参数。步长的平均准确性±精度为 1.5±6.8cm，步速为 1.4±5.6cm/s，足离地间隙为 1.9±2.0cm，转弯角度为 1.6±6.1°。在 6MWT 期间，年轻和老年志愿者的步态表现存在差异，特别是在足离地间隙方面。该方法允许分析步态的各个方面，包括转弯、步态起始和结束，或周期间的变异性。该系统重量轻，易于穿戴和使用，适用于需要在实验室环境之外对步态进行客观评估的临床应用。
