EMG Biofeedback with AMES

描述（由申请人提供）：该项目的长期目标是能够使用一种名为“艾姆斯”的新型治疗方案和机器人设备有效地治疗瘫痪的中风患者，AMES是具有增强感觉的辅助运动的首字母缩写。在艾姆斯中，患者使用自主关节扭矩的生物反馈来辅助机器人设备的运动，而运动的感觉通过肌腱振动来增强。在一项临床前试验中，我们发现艾姆斯在恢复大多数严重残疾的慢性卒中患者（>2年事件）的上肢和下肢功能运动方面有效。入组时，这些受试者的肢体力量正常值<第30百分位数。尽管我们在治疗严重残疾的中风患者方面取得了成功，但艾姆斯治疗并没有恢复关节的功能性运动（例如，手指、手腕和脚踝）被中风完全麻痹。然而，使用EMG记录，我们发现大多数瘫痪的中风患者保留了主动激活“瘫痪”肌肉的能力。由于活动是如此微弱，它与对抗性痉挛和共同收缩竞争，这些人无法在一个或另一个方向移动关节。拟议项目的目标是将EMG生物反馈纳入艾姆斯治疗中，作为扭矩生物反馈的替代方案，以有效治疗深度瘫痪的中风患者。在第一阶段申请中提出了两个具体目标。第一个具体目标是将EMG信号转换为图形显示器上有用的生物反馈。必须完成两项任务：（1）开发和测试软件，对EMG信号进行低通滤波，使带宽（~0-2 Hz）与患者的努力相匹配，以及（2）以患者直观的方式在图形显示器上呈现来自2个激动剂和2个拮抗剂肌肉的活动，以纠正其协同失调。第二个具体目标是所提出的EMG采集在肌腱振动的存在下，振动器产生的机械和电气干扰必须在EMG记录中减少到不减少生物反馈的信息内容的水平。具体目标2是将这种干扰降低到总信号幅度的=2%。我们建议探索一些替代解决方案的机械工件和电气工件的问题，并实施有效的解决方案，同时最大限度地降低成本。一旦我们用艾姆斯设备实现了有用的EMG生物反馈，该项目的第二阶段将在对照临床试验中测试该方法。这个项目针对一个或多个关节完全瘫痪的慢性中风患者的亚组，但他们保留了一些主动激活“瘫痪”肌肉的能力。我们的初步研究表明，在美国的500万慢性中风患者中，有相当大比例的患者在一个或多个关节瘫痪，同时保留了一些“瘫痪”肌肉的自愿激活。所提出的技术旨在逆转瘫痪关节的协同失调，并通过进一步治疗恢复功能性运动。一项单独的临床前试验表明，艾姆斯治疗可有效恢复因创伤性脑损伤（TBI）而长期残疾的个体的功能性运动。目前美国约有100万慢性残疾TBI患者。

DESCRIPTION (provided by applicant): The long-range goal of this project is to be able to treat effectively plegic stroke victims using a novel therapeutic regimen and robotic device called "AMES," an acronym for Assisted Movement with Enhanced Sensation. In AMES, the patient assists the motion of the robotic device using biofeedback of voluntary joint torque, while the sensation of motion is enhanced by tendon vibration. In a pre-clinical trial, we showed AMES to be effective at restoring functional movement in both upper and lower extremities in a majority of profoundly disabled chronic stroke patients (>2 yr event). At enrollment, these subjects ranked <30th percentile of normal limb strength. Despite our success at treating profoundly disabled stroke victims, AMES treatment did not restore functional movement at joints (e.g., fingers, wrist, and ankle) rendered completely plegic by the stroke. Using EMG recordings, however, we found that most plegic stroke patients retain the ability to activate voluntarily the 'plegic' muscles. Because the activity is so weak and it competes with antagonistic spasticity and co-contraction, these individuals are unable to move the joint in one or the other direction. The goal of the proposed project is to incorporate EMG biofeedback into the AMES treatment, as an alternative for torque biofeedback, in order to treat effectively profoundly plegic stroke patients. There are 2 specific aims proposed in this Phase I application. The first specific aim is to convert EMG signals into useful biofeedback on a graphics display. Two tasks must be accomplished: (1) to develop and test software to low-pass filter the EMG signals so the bandwidth (~0-2 Hz) is matched to that of the patient's efforts and (2) to present on a graphics display the activity from 2 agonist and 2 antagonist muscles in a way that it is intuitive to the patients how to correct their dyssynergia. The second specific aim is necessitated by the proposed EMG acquisition in the presence of tendon vibration-mechanical and electrical interference produced by the vibrators must be reduced in the EMG recording to levels where it does not reduce the information content of the biofeedback. Specific Aim 2 is to reduce this interference down to =2% of the overall signal amplitude. We propose to explore a number of alternative solutions to the mechanical artifact and electrical artifact problems and to implement solutions that are effective while minimizing cost. Once we have implemented useful EMG biofeedback with the AMES device, Phase II of this project will test the methodology in a controlled clinical trial. This project addresses a sub-group of chronic stroke patients with complete plegia at one or more joints, but who retain some ability to activate voluntarily the 'plegic' muscles. Our preliminary studies indicate that a sizable proportion of the 5 million chronic stroke patients in the US are plegic at one or more joints while retaining some voluntary activation of the 'plegic' muscles. The proposed technology is designed to permit the reversal of dyssynergia at plegic joints and, with further therapy, to restore functional movement. A separate pre-clinical trial indicates that AMES treatment is effective at restoring functional movement in individuals who chronically disabled by traumatic brain injury (TBI). There are current about 1 million chronically disabled TBI patients in the US.