A Joint-Coupled Controlled-Brake Orthosis System for Hybrid FES Gait Restoration

描述（由申请人提供）：本研究的目的是恢复脊髓损伤（SCI）患者的行走能力。先前的研究（由几位研究人员进行）已经证明，FES可以有效地恢复腿部活动性（在稳定性辅助装置的帮助下），并且这种腿部活动性可以为SCI用户提供显着的生理和心理益处。由于潜在的崩溃（肌肉疲劳）和需要引导不受控制的自由度，混合系统似乎提供了商业上可行的步态恢复的最大希望。因此，各种研究人员最近的努力已经（并且正在）集中在混合动力系统的开发上。尽管如此，商业上可行的混合FES系统还不存在。该提议的目的是开发一种商业上可行的步态恢复系统，即消除塌陷（由于肌肉疲劳）的可能性、具有低的实施和使用阈值、提供稳定、有效的步态（即，主要由下肢提供动力的摆动步态），并且独立地且以最小程度的努力穿上和脱下。所提出的系统利用了混合FES方法，它结合了两个通道的表面刺激（每条腿的股四头肌）与一个独特的微机控制的矫形器，称为关节耦合控制制动矫形器（JCO），其组合提供了一个稳定的，安全的，商业上可行的步态恢复系统瘫痪的人。具体地，表面刺激的使用提供了低的实现阈值，但是以有限的肌肉接近（即，不能直接进入深髋屈曲肌肉）。该限制通过矫形器来解决，该矫形器包括膝关节的机械偏置并且单向地将膝关节屈曲耦合到髋关节屈曲，并且通过该组合来提供可靠的摆动通过步态所需的髋关节和膝关节屈曲。通过在髋关节和膝关节处使用独特的可控制动器来提供等长扭矩（代替肌肉刺激），大大减少了肌肉疲劳的影响，并且由于膝关节制动器通常被锁定，因此基本上消除了崩溃的风险（即使在电源故障的情况下）。矫形器提供了对肢体轨迹的平滑的、可重复的控制，这通过关节角度传感器和比例可控制动器的组合来实现，关节角度传感器和比例可控制动器用于引导肢体（即，关节角度）沿所需轨迹沿着运动。由于用于步态的动力由代谢源提供，因此矫形器需要最小量的板载动力。最后，该方法被设计成以最小的用户努力促进独立的穿脱。因此，所提出的系统具有以下特性（即，故障安全、低疲劳、适度用力、容易穿戴/穿戴、低电力需求）。如果成功的话，所提出的方法可以直接转变为可行的商业产品，因此可以显著改善许多患有下肢完全瘫痪的SCI个体的生活质量。公共卫生相关性：目前在美国有大约255，000名脊髓损伤的个体，每年大约有12，000例新的损伤，其中大约6300例（每年的病例）导致腿部完全瘫痪，具有足够的剩余手臂功能以潜在地使用所提出的步态恢复方法。截瘫造成的重大损害之一是腿部活动能力的丧失。本文提出的系统旨在作为对（而不是作为轮椅的替代品），并且特别是旨在提供轮椅不能提供的腿部活动性的许多生理和心理益处，例如减少骨质疏松症、减少褥疮溃疡的发生率、改善心血管健康、改善肠和膀胱功能、减少痉挛和增加士气、自我形象，和自尊。

DESCRIPTION (provided by applicant): The objective of this research is to restore the ability to walk to spinal cord injured (SCI) individuals. Previous studies (by several researchers) have demonstrated that FES can effectively restore legged mobility (with the help of a stability aid), and that such legged mobility can provide significant physiological and psychological benefits to SCI users. Due to the potential of collapse (from muscle fatigue) and the need to guide uncontrolled degrees of freedom, hybrid systems appear to offer the greatest promise for commercially viable gait restoration. As such, recent efforts by various researchers have focused (and are focusing) on the development of hybrid systems. Despite this, a commercially viable hybrid FES system does not yet exist. The intent of this proposal is to develop a commercially feasible gait restoration system, namely one that eliminates the possibility of collapse (due to muscle fatigue), has a low threshold for implementation and use, provides a stable, efficient gait (i.e., a swing-through gait primarily powered by the lower limbs), and is donned and doffed independently and with a minimal level of effort. The proposed system utilizes a hybrid FES approach, which combines two channels of surface stimulation (quadriceps of each leg) with a unique microcomputer-controlled orthosis, called a joint-coupled controlled-brake orthosis (JCO), the combination of which provides a stable, safe, commercially viable gait restoration system for paralyzed persons. Specifically, the use of surface stimulation pro- vides a low threshold of implementation, but at the cost of limited muscular access (i.e., inability to directly access deep hip flexion muscles). This limitation is addressed by the orthosis, which includes a mechanical biasing of the knee joint and unidirectionally couples knee flexion to hip flexion, and with this combination pro- vides the hip and knee flexion required for reliable swing-through gait. The effect of muscle fatigue is greatly diminished by utilizing unique controllable brakes at the hip and knee joints to provide isometric torques (in place of muscle stimulation), and since the knee brakes are normally locked, the risk of collapse is essentially eliminated (even in the event of a power failure). The orthosis provides for smooth, repeatable control of limb trajectories, which is enabled by the combination of joint angle sensors and the proportionally controllable brakes, which are used to guide the limbs (i.e., joint angles) along a desired trajectory. Since the power for gait is provided by metabolic sources, the orthosis requires a minimal amount of on-board power. Finally, the approach is designed to facilitate independent donning and doffing with minimal user effort. As such, the pro- posed system has the characteristics (i.e., fail-safe, low fatigue, moderate exertion, easy don/doff, low electric- al power requirements) of a commercially viable self-contained gait restoration system. If successful, the pro- posed approach could transition in a direct manner to a viable commercial product, and therefore could significantly improve the quality of life of many SCI individuals suffering from complete paralysis of the lower limb. PUBLIC HEALTH RELEVANCE: There are currently about 255,000 spinal cord injured individuals in the United States, with roughly 12,000 new injuries sustained each year, of which approximately 6300 of these (cases per year) result in complete paralysis of the legs with sufficient remaining arm functionality to potentially use the proposed gait restoration approach. Among the significant impairments resulting from paraplegia is the loss of legged mobility. The system proposed herein is intended as a supplement to (and not as a replacement of) a wheelchair, and in particular is intended to provide many of the physiological and psychological benefits of legged mobility that a wheelchair cannot, such as decreased osteoporosis, reduced incidence of decubitus ulcers, improved cardiovascular health, improved bowel and bladder function, reduced spasticity, and increased morale, self-image, and self- esteem.