Effect of Upper Arm Support on the Hemiparetic Arm

中风导致的中度至重度轻偏瘫可能对许多人产生重大影响， 常见的日常生活活动（ADL），导致严重依赖照顾者。一 中风中常见的是异常肌肉协同作用的发展， 当患者用力抬起手臂时，手腕和手指会不由自主地弯曲和闭合。这 导致可触及区域的损失和手的闭合，从而极大地损害其使用。然而已经 显示当手臂被支撑并且外力被用来抬起手臂时，这种非自愿的 活动不会被激发。任何恢复手臂和手功能的干预措施， 由于严重到中度中风引起的轻偏瘫必须首先解决肩肘关节的缓解问题， 屈曲协同作用。 拟议工作的目标是证明积极支持该部门的有效性 以帮助肩外展，长期目标是发展一个小的， 机器人辅助系统通过使用外部设备，而不是人的自愿努力 为了对抗重力，肩肘屈曲协同作用的效果将显著降低; 潜在地允许使用者保持有效的自主运动控制和力量。 虽然早期的研究使用前臂或手腕的手臂支撑来显示屈曲的减少， 协同作用，这种布置不适用于佩戴的设备。 所提出的研究将通过满足两个具体目标来实现。一是 描述中风后偏瘫手臂的动力学、运动学和功能能力 同时得到支持。这将包括测试受试者产生力的能力的实验 等比例地，在他们面前的整个工作空间，并打开手，有和没有 由市售机器人手臂提供的手臂支撑。第二个目标是量化 肌肉活动的变化是由于异常屈曲协同作用的减少， 近端臂支撑。该目的将用于测量EMG的时间和幅度变化 臂屈肌的信号，因为它们与肩部肌肉EMG活动相关，并且量化和 证明肌肉活动的变化导致异常屈曲协同作用的减少。 与目标1类似，将在重力支撑和无支撑之间比较EMG模式 条件 这项工作提出了一种新的放置手臂的支持，以减少屈曲的协同作用。这 这项工作对于未来为轻偏瘫患者开发手臂辅助系统至关重要 是中风造成的通过将支撑件的位置移动得更靠近身体， 临床上可部署的，和用户可接受的手臂支持系统可以在以后的项目中开发。

Moderate to severe hemiparesis as a result of stroke can have a significant impact upon many common activities of daily living (ADLs), resulting in significant dependence on caregivers. One common occurrence in stroke is the development of abnormal muscle synergies where the elbow, wrist, and fingers involuntarily flex and close when the patient exerts effort to lift the arm. This results in a loss of reach area and closing of the hand, greatly impairing its use. However, it has been shown that when the arm is supported and an outside force is used to lift the arm, this involuntary activity is not elicited. Any intervention to restore arm and hand function in individuals with hemiparesis due to severe to moderate stroke must first address the alleviation of this shoulder-elbow flexion synergy. The objective of the proposed work is to demonstrate the effectiveness of active support of the arm proximal to the elbow to assist shoulder abduction with the long-term goal of developing a small, worn, robotic assistance system. By using an external device rather than the person's voluntary effort to counter gravity, the effects of the shoulder-elbow flexion synergy will be significantly reduced; potentially allowing the user's retained voluntary movement control and strength to be effective. While earlier work has used arm support at the forearm or wrist to show a reduction in flexion synergy, this arrangement is not amenable to a worn device. The research proposed will be achieved through meeting two Specific Aims. The first is to characterize the kinetics, kinematics, and functional capabilities of the post-stroke hemiparetic arm while being supported. This will consist of experiments to test subjects' abilities to produce force isometrically, reach throughout the workspace in front of them, and open the hand with and without arm support provided by a commercially available robotic arm. The second Aim will be to quantify the changes in muscle activity as a result of reduction in abnormal flexion synergy afforded by proximal arm support. This Aim will serve to measure the timing and magnitude changes of EMG signals of the arm flexors as they relate to shoulder muscle EMG activity and quantify and demonstrate the changes in muscle activity that lead to a reduction in abnormal flexion synergy. Similar to Aim 1, EMG patterns will be compared between the gravity supported and the unsupported conditions. The work proposed represents a novel placement of arm support to reduce flexion synergies. This work is critical to the development of future arm assistance systems for individuals with hemiparesis as a result of stroke. By moving the location of the support closer to the body, a lightweight, wearable, clinically deployable, and user acceptable arm support system can be developed in later projects.