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

描述(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。以前的研究(由几位研究人员)已经证明，FES可以(在稳定器的帮助下)有效地恢复腿部活动，并且这种腿部活动可以为SCI使用者提供显著的生理和心理好处。由于潜在的崩溃(由于肌肉疲劳)和引导不受控制的自由度的需要，混合系统似乎为商业上可行的步态恢复提供了最大的希望。因此，各种研究人员最近的努力都集中在混合系统的开发上。尽管如此，商业上可行的混合FES系统还不存在。这项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(由于肌肉疲劳)崩溃的可能性，具有较低的实施和使用门槛，提供稳定、有效的步态(即主要由下肢提供动力的回旋步态)，并且可以独立穿戴和脱掉，并且努力程度最低。该系统采用混合FES方法，将两个表面刺激通道(每条腿的股四头肌)与独特的微计算机控制的矫形器相结合，称为关节耦合受控制动矫形器(JCO)，其组合为瘫痪患者提供了稳定、安全、商业可行的步态恢复系统。具体地说，表面刺激的使用提供了较低的实施门槛，但代价是肌肉接触有限(即无法直接接触髋关节深屈肌)。矫形器解决了这一限制，它包括膝关节的机械偏向，单向地将膝关节屈曲与髋关节屈曲相结合，通过这种组合提供可靠的摆动步态所需的髋关节和膝关节屈曲。通过在髋关节和膝关节使用独特的可控制动器来提供等距扭矩(代替肌肉刺激)，肌肉疲劳的影响大大减弱，而且由于膝关节制动器通常是锁定的，基本上消除了崩溃的风险(即使在停电的情况下)。该矫形器提供了对肢体轨迹的平稳、可重复的控制，这是通过关节角度传感器和比例可控刹车的组合实现的，刹车用于引导肢体(即关节角度)沿着所需的轨迹。由于步态的动力是由新陈代谢来源提供的，因此矫形器需要最低限度的车载动力。最后，该方法被设计为以最少的用户努力来促进独立的穿戴和道夫。因此，提出的系统具有商业上可行的自给式步态恢复系统的特征(即故障安全、低疲劳、中等强度、易脱/脱、低电功率要求)。如果成功，提出的方法可以直接转化为可行的商业产品，因此可以显著改善许多患有下肢完全瘫痪的脊髓损伤患者的生活质量。公共卫生相关性：目前美国约有255,000名脊髓损伤患者，每年约有12,000名新损伤，其中约6,300例(每年)导致腿部完全瘫痪，并有足够剩余的手臂功能，有可能使用拟议的步态恢复方法。截瘫造成的重大损害之一是失去腿部活动能力。这里提出的系统旨在作为轮椅的补充(而不是取代)，尤其是旨在提供轮椅无法提供的许多腿部活动的生理和心理好处，例如减少骨质疏松症、减少压疮的发生率、改善心血管健康、改善肠道和膀胱功能、减少痉挛、提高士气、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.