Department of Physical Therapy, Faculty of Nursing and Rehabilitation, Konan Women's University, 6-2-13 Morikita-machi, Higashinada-ku, Kobe 658-0001, Hyogo, Japan.
Department of Rehabilitation, Fukuoka Orthopedic Hospital, 2-10-50 Yanagochi, Minami-ku, Fukuoka 815-0063, Fukuoka, Japan.
Sensors (Basel). 2022 Aug 27;22(17):6460. doi: 10.3390/s22176460.
We developed a novel quantitative method to assess varus thrust during walking using acceleration data obtained from an inertial measurement unit (IMU). This study aimed to examine the reliability of the developed index and to evaluate its ability to distinguish patients with knee osteoarthritis (OA) with varus thrust from healthy adults. Overall, 16 patients with knee OA and 16 healthy adults walked on a treadmill with IMUs attached to the tibial tuberosity and lateral femoral condyle. As an index of varus thrust, we used the root mean square (RMS) of acceleration in the mediolateral direction. This value was adjusted by dividing it by swing speed while walking (adjusted RMS, A-RMS) because the RMS of the acceleration was strongly coupled with the speed of motion. The intraclass correlation coefficients of A-RMS of the tibia and femur were 0.85 and 0.73, respectively. Significant differences were observed in the A-RMSs of the tibia and femur, with large effect sizes between the patients with knee OA and healthy adults (Cohen's d: 1.23 and 0.97, respectively). Our results indicate that A-RMS has good test-retest reproducibility and can differentiate patients with varus thrust from healthy adults.
我们开发了一种新的定量方法，使用惯性测量单元（IMU）获得的加速度数据来评估步行时的内翻推力。本研究旨在检验所开发指标的可靠性，并评估其区分有内翻推力的膝骨关节炎（OA）患者与健康成年人的能力。总体而言，16 名膝骨关节炎患者和 16 名健康成年人在跑步机上行走，胫骨结节和外侧股骨髁上附有 IMU。我们使用中-侧方向加速度的均方根（RMS）作为内翻推力的指标。由于加速度的 RMS 与运动速度强烈耦合，因此通过除以行走时的摆动速度来调整该值（调整后的 RMS，A-RMS）。胫骨和股骨的 A-RMS 的组内相关系数分别为 0.85 和 0.73。在胫骨和股骨的 A-RMS 中观察到显著差异，膝骨关节炎患者与健康成年人之间的差异具有较大的效应量（Cohen's d：分别为 1.23 和 0.97）。我们的结果表明，A-RMS 具有良好的测试-重测可重复性，可以区分有内翻推力的患者和健康成年人。
