Novel training environment to normalize altered finger force direction post stroke

据估计，每年有15,000名退伍军人中风。中风是美国长期残疾的主要原因。 新的中风估计花费1.11亿美元用于急性住院治疗，7500万美元用于急性后住院治疗， 以及8800万美元用于VHA中风后前六个月的后续护理。然而，超过三分之二的中风患者 幸存者有持续的手部损伤，显著降低了他们进行日常活动的能力， living.灵巧地操纵物体，如工具，盘子和智能手机，不仅需要合适的手， 运动，但也有适当的力量控制。不仅是运动，而且手指的力量控制也已经被 显示在中风后严重受损，导致物体被错误处理，或根本不处理， 任务执行失败。运动控制文献表明，手指运动和力控制涉及两个 独立的神经控制，因此必须独立康复。然而，传统的鞋面 肢体治疗专门集中在运动控制上，而不涉及手的力量控制。这一差距 在治疗中，由于缺乏对患者的意志手指力控制提供明确反馈的工具。到 为了弥补这一差距，开发了一种新的部队训练工具。这个工具使中风幸存者能够练习 在三维（3D）中产生意志手指力，并对方向控制进行显式反馈， 已知的临床运动学习策略。这种3D力量训练的初步测试显示， 手功能改善（通过行动研究臂、箱和块测试、ARAT和BBT评估） 严重手部损伤的中风幸存者。本项目的目的是确定3D手指力是否 训练是恢复中风后手功能的有效工具。60名中风的退伍军人， 可触知意志握力的严重手部损伤将被随机分配到实验组或对照组。 或对照组，按损伤水平分层。两组都将接受每周3次1小时的训练，持续6周。 实验组将接受3D力的明确反馈，而控制组将接受3D力的反馈。 1D仅在计算机屏幕上显示。该控制条件类似于简单的挤压球重复。培训将 通过改变姿势要求和增加力量水平来增加屈曲协同作用的影响， 引入反馈延迟，并结合单侧/双侧活动。评价将在基线时进行，每2 在6周干预期间和1个月随访时。目的1：确定3D指力训练的效果 手部行为功能假设：实验组的手功能比对照组有更大的改善 组将使用ARAT、BBT和卒中影响量表评估手功能。干预的意义 将通过定性访谈进行评估。目的2：确定3D指力训练对指力的影响 方向控制假设：实验组将比对照组获得更大的指导手指力量的能力 在训练之后。引导指力的能力将被量化为意志指力与 目标方向。目的3：确定力方向改善的生物力学机制 控制假设：训练可以改善肌肉协调性。改善肌肉协调性， 通过可获得的肌肉激活模式的扩展、运动复杂性的增加、 轻瘫与非轻瘫的协同结构，并减少异常屈曲协同过程中， 到达/抓取/运输/释放。还将评估手臂协调性。一个定制的OpenSim手指模型将 用于解释肌肉协调性变化导致增强的直接生物力学机制 指力方向。影响：这项研究将为力量控制提供一种治疗方法，从而解决未得到满足的问题。 目前的康复需要完全集中在运动练习上。这项研究还将确定 潜在的生物力学机制以及训练对手部功能使用的影响。因此，在本发明中， 这项研究有望增强手的功能，从而提高退伍军人的独立性和生活质量 中风

Estimated 15,000 Veterans suffer a stroke each year. Stroke is a leading cause of long-term disability in the US. New strokes cost an estimated $111 million for acute inpatient care, $75 million for post-acute inpatient care, and $88 million for follow-up care in the first six months post-stroke in VHA. Yet, more than two thirds of stroke survivors have persistent hand impairment that significantly diminishes their abilities to perform activities of daily living. Dexterous manipulation of objects, such as tools, dishes, and smart phones, require not only proper hand movement, but also proper force control. Not only movement, but also control of forces from fingers has been shown to be profoundly impaired following stroke, resulting in the object being mishandled, or not handled at all, and failure at task execution. Motor control literature shows that finger movement and force control involve two independent neural controls, and therefore must be independently rehabilitated. However, conventional upper extremity therapy focuses on movement control exclusively and does not address hand force control. This gap in treatment is due to a lack of tools to provide explicit feedback on patients’ volitional finger force control. To address this gap, a novel force training tool has been developed. This tool enables stroke survivors to practice volitional finger force generation in three-dimension (3D) with explicit feedback on directional control, per best known clinical motor learning strategy. Preliminary testing of this 3D force training showed significant improvement in hand function (assessed by the Action Research Arm and Box and Block Tests, ARAT and BBT) in stroke survivors with severe hand impairment. The objective of this project is to determine if 3D finger force training is an effective tool in restoring hand function post stroke. Sixty Veterans with stroke with moderate to severe hand impairment with palpable volitional grip force will be randomly be assigned to either the experimental or control group, stratified by impairment level. Both groups will undergo 3 1-hr training sessions per week for 6 weeks. The experimental group will receive explicit feedback in 3D force, whereas the control group will receive feedback in 1D only on a computer screen. This control condition is analogous to simple squeeze ball repetitions. Training will progress by increasing influence of flexion synergy by varying posture requirements and increasing force level, introducing feedback delay, and incorporating unilateral/bilateral activity. Evaluation will occur at baseline, every 2 weeks during 6-week intervention, and at 1-month follow-up. Aim 1: Determine the effect of 3D finger force training on behavioral hand function. Hypothesis: Hand function will improve more in the experimental group than the control group. Hand function will be assessed using ARAT, BBT, and Stroke Impact Scale. Meaningfulness of the intervention will be assessed via qualitative interviews. Aim 2: Determine the effect of 3D finger force training on finger force direction control. Hypothesis: The experimental group will achieve greater ability to direct finger force than control after the training. The ability to direct finger force will be quantified as angular deviation of volitional finger force from the target direction. Aim 3: Determine the biomechanical mechanisms underlying improvement in force direction control. Hypothesis: The training results in improved muscular coordination. Improved muscular coordination will be assessed by expansion of the attainable muscle activation patterns, increased motor complexity, similarity between the paretic vs. nonparetic synergy structures, and reduced abnormal flexion synergy during reach/grasp/transport/release. Hand-arm coordination will also be assessed. A custom OpenSim finger model will be used to explain the direct biomechanical mechanism by which changes in muscular coordination leads to enhanced finger force direction. Impact: This research will provide a treatment for force control, thereby addressing the unmet need in the current rehabilitation exclusively focused on movement practice. This research will also determine the underlying biomechanical mechanisms as well as the training’s impact on functional use of the hand. As a result, this research is expected to enhance hand function, thus increasing independence and quality of life for Veterans with stroke.