IEEE Trans Neural Syst Rehabil Eng. 2017 Nov;25(11):2196-2203. doi: 10.1109/TNSRE.2017.2714203. Epub 2017 Jun 9.
Spasticity is an important factor in designing wearable and lightweight exoskeleton neurorehabilitation robots. The proposed study evaluates biomechanical reactions of an exoskeleton robot to spasticity and establishes relevant guidelines for robot design. A two-axis exoskeleton robot is used to evaluate a group of 20 patients post-stroke with spastic elbow and/or wrist joints. All subjects are given isokinetic movements at various angular velocities within the capable range of motion for both joints. The resistance torque and corresponding angular position at each joint are recorded continuously. Maximal resistance torques caused by low (modified Ashworth scale (MAS) 0, 1), intermediate (MAS 1+), and high (MAS 2 and 3) grade spasticity were 3.68 ± 2.42, 5.94 ± 2.55, and 8.25 ± 3.35 Nm for the elbow flexor ( , between each grades) and 4.23 ± 1.75, 5.68 ± 1.96, and 5.44 ± 2.02 Nm for the wrist flexor ( , for low versus intermediate, low versus high grade spasticity). The angular velocity did not significantly influence maximal resistance torque in either joint. The catch occurred more quickly at higher velocities for low and intermediate elbow flexor spasticity ( ). Spasticity caused considerable resistance to the robots during mechanically actuated movements. The resistance range according to the degree of spasticity should be considered when designing practical neurorehabilitation robots.
痉挛是设计可穿戴、轻便的外骨骼神经康复机器人的一个重要因素。本研究评估了外骨骼机器人对痉挛的生物力学反应，并为机器人设计制定了相关指南。使用双轴外骨骼机器人对 20 名脑卒中后肘部和/或腕部关节痉挛的患者进行评估。所有受试者在两个关节的运动范围内的不同角速度下进行等速运动。连续记录每个关节的阻力扭矩和相应的角度位置。低（改良 Ashworth 量表（MAS）0、1）、中（MAS 1+）和高（MAS 2 和 3）级痉挛时，肘部屈肌的最大阻力扭矩分别为 3.68 ± 2.42、5.94 ± 2.55 和 8.25 ± 3.35 Nm（肘部屈肌，各等级之间），腕部屈肌的最大阻力扭矩分别为 4.23 ± 1.75、5.68 ± 1.96 和 5.44 ± 2.02 Nm（腕部屈肌，低与中、低与高级痉挛之间）。角速度对两个关节的最大阻力扭矩均无显著影响。在较低和中等程度的肘部屈肌痉挛时，高速运动的捕获速度更快（ ）。痉挛在机械驱动运动中对机器人造成了相当大的阻力。在设计实用的神经康复机器人时，应根据痉挛程度考虑阻力范围。
