Nerve-Muscle Graft Chamber for Prosthesis Control

描述(由申请人提供)：目标是开发一种神经-肌肉接口，使截肢者能够同时控制多自由度假肢中的所有执行器。控制信号将来自自然产生的神经活动，起源于被切断的神经的残端。提出的方法将开发一种通用的神经肌肉移植技术，将被切断的神经移植到一个装有自体肌肉切片和记录电极的房间中。神经控制可能比当前使用的肌电控制更自然，因为先前由特定运动束提供的相同功能被引导到相应的假肢致动器，用于与正常肢体中的同时关节控制，而不是如商业上可用的技术中的顺序控制。这里的方法进一步发展和扩展了肌肉神经移植技术，即被切断的神经的残端被移植到宿主肌肉上，并如Kuiken等人最近所证明的那样发生重新神经支配。在芝加哥。移植的神经-肌肉单位的自愿激活产生肌电(EMG)信号，用于假肢控制，比微弱的神经活动更可靠地被感知。目前实施的Kuiken方法的一个缺点是必须牺牲健康的肌肉来创建新的界面，这种方法将截肢的神经残端转移到正常肌肉上。此外，宿主肌肉变得受到最初针对多个其他肌肉的神经束的混合支配，这降低了神经命令所固有的特异性。目前提出的将包含在隔室阵列中的小肌肉切片带到被切断神经的单个神经束的方法具有能够单独与每个运动束连接的优点。这可以大大增加单一用途的自然控制信号的数量，而不会牺牲健康的肌肉，而且由于肌肉被隔离在室内，因此不可能存在串扰。作为进一步的优势，所提出的方法可以用于非常短的神经节段，并且神经可以在其原始位置进行器械，而不是必须被移位。第一阶段研究的目的是在动物模型中证明，移植的运动神经可以对驻留在室内的小片肌肉进行功能性神经支配，由此产生的功能运动单位集合将能够提供分级良好的肌电活动，可以在长期内以恒定的特征和合理的疲劳特性进行记录。在第二阶段，植入的小室将安装“机载”放大器和遥测电路，InnerSea技术公司目前正在为其他康复应用开发这些电路。与目前使用的表面肌电记录相比，这将提供来自许多外围电机控制通道的异常清晰和稳定的肌电记录。与公共健康相关：这项拟议的技术开发如果成功，将使截肢者能够更好地控制他们的电动假肢。目前的技术受到极少数控制信号源的严重限制，所以每个执行器的控制通常是一次一个地完成--例如，要到达并抓住汽水罐，首先伸展肘部，然后手腕略微旋转，然后手张开，然后手肘调整，然后手腕旋转，然后手闭合等等。所提出的技术将使所有执行器和更多的执行器能够同时移动，从而恢复基本上正常的肢体功能。

DESCRIPTION (provided by applicant): The objective is to develop a nerve-muscle interface that allows amputees to obtain simultaneous control of all actuators in a multi-degree of freedom prosthetic arm. Control signals will be derived from naturally produced neural activity originating in the stumps of the amputated nerves. The proposed approach will develop a universal nerve-muscle replant technique by grafting amputated nerves into a chamber which contains autologus muscle slices and recording electrodes. Neural control can be more natural than currently used myoelectric control since the same functions previously served by particular motor fascicles are directed to the corresponding prosthesis actuators, for simultaneous joint control as in normal limbs rather than sequential control as in commercially available technology. The approach here further develops and extends muscle-nerve grafting techniques whereby the stump of an amputated nerve is grafted onto a host muscle, and re-innervation occurs as recently demonstrated by Kuiken et al. in Chicago. Voluntary activation of the grafted nerve-muscle unit produces ElectroMyoGraphic (EMG) signals for prosthetic control that can be sensed more reliably than the feeble neural activity. A drawback of the presently implemented Kuiken approach of transferring an amputated nerve stump to a normal muscle is that a healthy muscle must be sacrificed to create the new interface. Also, the host muscle becomes innervated by a mix of nerve fascicles originally targeted at multiple other muscles which reduces the specificity inherent in the neural commands. The present proposed approach of bringing small muscle slices contained in a compartmented array to the individual fascicles of an amputated nerve has the advantage of being able to interface individually with each motor fascicle. This can greatly increase the number of single purpose natural control signals without sacrificing a healthy muscle, and since muscles are isolated in chambers, there is no crosstalk possible. As a further advantage, the proposed method can be used with very short nerve segments, and the nerves can be instrumented in their native locations rather than having to be trans-located. The Phase 1 study is intended to demonstrate in an animal model that small slices of muscle residing in a chamber can be functionally innervated by grafted motor nerves and that the resultant ensemble of functional motor units will be able to provide well graded EMG activity that can be recorded over a long period with constant characteristics and reasonable fatigue properties. In Phase 2, the implanted chamber will be fitted with 'onboard' amplifier and telemetry circuitry that is currently under development by InnerSea Technology for other rehabilitation applications. This will provide exceptionally clear and stable EMG recordings from many peripheral motor control channels in comparison to the current use of surface EMG recordings. PUBLIC HEALTH RELEVANCE: This proposed technology development, if successful, will allow amputees to better control their electrically powered prostheses. Current technology is severely limited by very few control signal sources, so control of each actuator is typically done one at a time -- so for example, to reach and grasp a soda can, first the elbow would be extended, then the wrist rotated somewhat, then the hand opened, then the elbow adjusted, then the wrist rotation adjusted, then the hand closed, etc. The proposed technology would enable simultaneous movement of all actuators, and many more actuators, thereby restoring essentially normal limb function.