Ecole Polytechnique Fédérale de Lausanne, Laboratory of Movement Analysis and Measurement, Lausanne, Switzerland.
J Biomech. 2011 Oct 13;44(15):2712-8. doi: 10.1016/j.jbiomech.2011.07.021.
This study aimed to design and validate the measurement of ankle kinetics (force, moment, and power) during consecutive gait cycles and in the field using an ambulatory system. An ambulatory system consisting of plantar pressure insole and inertial sensors (3D gyroscopes and 3D accelerometers) on foot and shank was used. To test this system, 12 patients and 10 healthy elderly subjects wore shoes embedding this system and walked many times across a gait lab including a force-plate surrounded by seven cameras considered as the reference system. Then, the participants walked two 50-meter trials where only the ambulatory system was used. Ankle force components and sagittal moment of ankle measured by ambulatory system showed correlation coefficient (R) and normalized RMS error (NRMSE) of more than 0.94 and less than 13% in comparison with the references system for both patients and healthy subjects. Transverse moment of ankle and ankle power showed R>0.85 and NRMSE<23%. These parameters also showed high repeatability (CMC>0.7). In contrast, the ankle coronal moment of ankle demonstrated high error and lower repeatability. Except for ankle coronal moment, the kinetic features obtained by the ambulatory system could distinguish the patients with ankle osteoarthritis from healthy subjects when measured in 50-meter trials. The proposed ambulatory system can be easily accessible in most clinics and could assess main ankle kinetics quantities with acceptable error and repeatability for clinical evaluations. This system is therefore suggested for field measurement in clinical applications.
本研究旨在设计并验证一种使用可移动系统在连续步态周期和现场测量踝关节动力学（力、力矩和功率）的方法。该可移动系统由足底压力鞋垫和脚部和小腿上的惯性传感器（3D 陀螺仪和 3D 加速度计）组成。为了测试该系统，12 名患者和 10 名健康的老年受试者穿着嵌入该系统的鞋子，多次穿过一个步态实验室，该实验室包括一个被 7 个摄像机包围的测力板，被视为参考系统。然后，参与者进行了两次 50 米试验，仅使用可移动系统。与参考系统相比，可移动系统测量的踝关节力分量和矢状面踝关节力矩的相关系数（R）和归一化均方根误差（NRMSE）均大于 0.94，小于 13%，适用于患者和健康受试者。踝关节横向力矩和踝关节功率的 R 值大于 0.85，NRMSE 小于 23%。这些参数还表现出较高的可重复性（CMC>0.7）。相比之下，踝关节冠状面力矩的误差较高，重复性较低。除了踝关节冠状面力矩之外，在 50 米试验中，可移动系统获得的动力学特征可以区分患有踝关节骨关节炎的患者和健康受试者。除了踝关节冠状面力矩外，该可移动系统可在大多数临床科室中方便获得，并且可以评估临床评估中具有可接受误差和可重复性的主要踝关节动力学参数。因此，建议将该系统用于临床应用中的现场测量。
