Hybrid Neuroprosthesis with a Variable Knee for Walking in SCI

用于 SCI 行走的具有可变膝关节的混合神经假体

• 批准号: 8977503
• 负责人: Rudi Kobetic
• 金额: --
• 依托单位: LOUIS STOKES CLEVELAND VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8977503
• 关键词: Acceleration; Address; American; Analysis of Variance; Body Weight; Braces-Orthopedic appliances; Chest; Confidence Intervals; Contracts; Dependence; Development; Devices; Electrodes; Employee Strikes; Ensure; Evaluation; Exercise; Experimental Designs; Feedback; Floor; Gait; Gastrocnemius Muscle; Heart; Heel; Hip region structure; Hybrids; Implant; Individual; Injury; Intramuscular; Joints; Knee; Lead; Leg; Lower Extremity; Lung; Measures; Medical; Motion; Muscle; Muscle Contraction; Orthotic Devices; Outcomes Research; Paralysed; Paraplegia; Performance; Persons; Phase; Physiologic pulse; Planning Techniques; Principal Investigator; Recruitment Activity; Research; Resistance; Safety; Shock; Signal Transduction; Skin; Spinal cord injury; Statistical Data Interpretation; Surface; System; Testing; Thigh structure; Thoracic spinal cord structure; Toes; Upper Extremity; Validation; Veterans; Walking; Wheelchairs; Work; ankle joint; base; bone; design; disability; electric impedance; evaluation/testing; exoskeleton; experience; fall risk; foot; functional outcomes; functional restoration; hamstring; improved; neuromuscular stimulation; neuroprosthesis; novel; orthotics; phase 1 study; prevent; prototype; quadriceps muscle; sensor

DESCRIPTION (provided by applicant): Objective - of the proposed research is to determine whether a novel hybrid neuroprosthesis (HNP) combining functional neuromuscular stimulation (FNS) and incorporating an advanced sensor based controlled variable impedance knee mechanism (VIKM) for walking in persons with paraplegia from spinal cord injury (SCI) can: (1) reduce impact forces during loading, improve forward momentum, reduce the fluctuations in vertical trunk motion, and improve foot-ground clearance during walking, and (2) restore stair descent and stand-to-sit functions by controlling the resistance to knee flexion while lowering of the body. Research Plan and Methodology - Three phases of the study are: 1) design, development, and validation of a closed loop control system using our novel variable impedance knee mechanism (VIKM) for modulation of stance phase knee flexion during gait, 2) evaluation of the functional benefits of incorporating knee flexion during stance phase of gait, and 3) evaluation of the ability of the VIKM to control stair descent and stand-to-sit maneuver. Five individuals with thoracic paraplegia from SCI will be recruited to test the VIKM as part of a hybrid neuroprosthesis (HNP). Subjects will be implanted with an eight channel pulse generator and intramuscular electrodes to activate iliopsoas/sartorius for hip/knee flexion, hamstrings for hip extension and quadriceps for knee extension and gastrocnemius for plantar flexion. These are key muscles for standing up, for initiating the swing and for forward propulsion of the body. The ankle joint will be spring loaded to return the foot to neutral during swing after actively plantar flexing for push-off. A prototype VIKM will be incorporated in previously designed exoskeleton and combined with implanted FNS systems to yield a novel HNP. A closed loop controller to modulate knee during gait will be based on feedback from sensors measuring foot-ground contact, hip and knee angles, thigh and leg velocity, and acceleration. A microcontroller will modulate damper current to control the resistance of the VIKM based on phase of the gait cycle. The finite state controller will control the VIKM and modulate stimulation to the paralyzed muscles. It will be first evaluated in two able-bodied individuals to ensure that it can accurately identify phases of gait (controller validation) and provide adequate resistance against knee collapse during stance (VIKM validation). The VIKM is expected to lessen the effect of impact and absorb shock during initial loading, reduce body center of mass displacement and improve toe clearance in early swing by regulating knee flexion. During stair descent and stand-to-sit maneuver the emphasis will be on lowering of the body and weight acceptance when the VIKM will perform most of the work normally performed by the eccentrically contracting muscles impossible to control with FNS. The controller will be optimized to reduce the need for upper extremity support during lowering and landing on the step below and sitting surface. Walking with the VIKM-based HNP will be compared to walking with FNS-only and conventional orthosis. Statistical analysis of the data will be carried out using a within subject experimental design to test effect of VIKM. Impact force at initial contact, average vertical motion of body center of mass, and stance phase knee flexion will be measured. A one-way repeated measure ANOVA will be used to test for significant differences and the Tukey honestly significant difference multiple comparison tests will be used to determine 95% confidence intervals.

描述（由申请人提供）： Objective - of the proposed research is to determine whether a novel hybrid neuroprosthesis (HNP) combining functional neuromuscular stimulation (FNS) and incorporating an advanced sensor based controlled variable impedance knee mechanism (VIKM) for walking in persons with paraplegia from spinal cord injury (SCI) can: (1) reduce impact forces during loading, improve forward momentum, reduce the fluctuations in vertical trunk motion,并在步行过程中提高脚地间隙，以及（2）通过控制膝盖屈曲的阻力，同时降低身体的阻力，以恢复楼梯下降和支架姿势功能。 Research Plan and Methodology - Three phases of the study are: 1) design, development, and validation of a closed loop control system using our novel variable impedance knee mechanism (VIKM) for modulation of stance phase knee flexion during gait, 2) evaluation of the functional benefits of incorporating knee flexion during stance phase of gait, and 3) evaluation of the ability of the VIKM to control stair descent and stand-to-sit maneuver. 将招募五名来自SCI的胸椎瘫痪的人作为杂种神经假体（HNP）的一部分测试VIKM。受试者将用八个通道脉冲发生器和肌内电极植入，以激活Iliopsoas/sartorius以进行髋/膝盖屈曲，用于髋关节伸展的腿筋和股四头肌进行膝关节伸展和胃肠痛。这些是站起来的关键肌肉，启动挥杆和前进的身体推进。脚踝关节将是春天 积极地弯曲以推开后，在秋千期间装满了脚。 原型VIKM将纳入先前设计的外骨骼中，并与植入的FNS系统结合使用，以产生新型的HNP。在步态过程中调节膝盖的闭环控制器将基于测量脚部接触，臀部和膝盖角，大腿和腿部速度以及加速度的传感器的反馈。微控制器将根据步态循环的相位调节阻尼电流以控制VIKM的电阻。有限国家控制器 将控制VIKM和调节刺激对瘫痪的肌肉。它将首先评估 在两个健全的个体中，以确保它可以准确识别步态的阶段（控制器 验证），并在立场期间提供了足够的抵抗力（VIKM验证）。预计VIKM可以通过调节膝盖屈曲，从而在初始加载过程中降低撞击和吸收冲击的影响，减少体内质量位移的中心并提高脚趾间隙。 在楼梯下降和站立式机动过程中，当VIKM将执行通常无法通过FNS控制的偏心收缩肌肉进行的大部分工作时，重点是降低身体和体重接受。将对控制器进行优化，以减少在降低和降落在下方和坐着表面的台阶上的上肢支撑的需求。 与基于VIKM的HNP同行将与仅使用FNS和常规矫形器走路进行比较。数据将使用主题实验设计进行VIKM测试效果进行数据进行统计分析。影响力 在初始接触时，将测量质量中心的平均垂直运动和姿势相膝屈曲。单向重复测量方差分析将用于测试显着差异，而Tukey对诚实的显着差异多重比较测试将用于确定95％的置信区间。