MENRVA, School of Engineering Science, Simon Fraser University , Burnaby, BC , Canada.
Front Bioeng Biotechnol. 2016 Mar 7;4:20. doi: 10.3389/fbioe.2016.00020. eCollection 2016.
Stroke is the leading cause of upper limb impairments resulting in disability. Modern rehabilitation includes training with robotic exoskeletons and functional electrical stimulation (FES). However, there is a gap in knowledge to define the detailed use of FES in stroke rehabilitation. In this paper, we explore applying closed-loop FES to the upper extremities of healthy volunteers and individuals with a hemiparetic arm resulting from stroke. We used a set of gyroscopes to monitor arm movements and used a non-linear controller, namely, the robust integral of the sign of the error (RISE), to assess the viability of controlling FES in closed loop. Further, we explored the application of closed-loop FES in improving functional tasks performed by individuals with stroke. Four healthy individuals of ages 27-32 years old and five individuals with stroke of ages 61-83 years old participated in this study. We used the Rehastim FES unit (Hasomed Ltd.) with real-time modulation of pulse width and amplitude. Both healthy and stroke individuals were tested in RISE-controlled single and multi-joint upper limb motions following first a sinusoidal trajectory. Individuals with stroke were also asked to perform the following functional tasks: picking up a basket, picking and placing an object on a table, cutting a pizza, pulling back a chair, eating with a spoon, as well as using a stapler and grasping a pen. Healthy individuals were instructed to keep their arm relaxed during the experiment. Most individuals with stroke were able to follow the sinusoid trajectories with their arm joints under the sole excitation of the closed-loop-controlled FES. One individual with stroke, who was unable to perform any of the functional tasks independently, succeeded in completing all the tasks when FES was used. Three other individuals with stroke, who were unable to complete a few tasks independently, completed some of them when FES was used. The remaining stroke participant was able to complete all tasks with and without FES. Our results suggest that individuals with a low Fugl-Meyer score or a higher level of disability may benefit the most with the use of closed-loop-controlled FES.
中风是导致上肢功能障碍和残疾的主要原因。现代康复包括使用机器人外骨骼和功能性电刺激（FES）进行训练。然而，在定义 FES 在中风康复中的详细应用方面，知识上仍存在差距。在本文中，我们探索了将闭环 FES 应用于健康志愿者和因中风导致偏瘫上肢的个体。我们使用一组陀螺仪来监测手臂运动，并使用非线性控制器，即误差符号的鲁棒积分（RISE），来评估闭环控制 FES 的可行性。此外，我们还探索了闭环 FES 在改善中风患者完成功能任务方面的应用。本研究共纳入了 4 名年龄在 27-32 岁的健康个体和 5 名年龄在 61-83 岁的中风个体。我们使用了 Rehastim FES 单元（Hasomed Ltd.），可以实时调制脉冲宽度和幅度。健康个体和中风个体均接受了 RISE 控制的单关节和多关节上肢运动测试，首先是正弦轨迹。中风个体还被要求完成以下功能任务：拿起篮子、在桌子上捡起并放置物体、切披萨、拉回椅子、用勺子吃饭、使用订书机和抓笔。健康个体在实验过程中被要求保持手臂放松。大多数中风个体能够在闭环控制 FES 的单一刺激下跟随手臂关节的正弦轨迹。一名无法独立完成任何功能任务的中风个体，在使用 FES 时成功完成了所有任务。另外三名无法独立完成部分任务的中风个体，在使用 FES 时完成了其中一些任务。其余的中风参与者在使用和不使用 FES 时都能够完成所有任务。我们的结果表明，Fugl-Meyer 评分较低或残疾程度较高的个体可能会从闭环控制 FES 的使用中受益最多。
