Spinal root stimulation for restoration of function in lower-limb amputees

脊髓根刺激恢复下肢截肢者的功能

• 批准号: 10357668
• 负责人: LEE E FISHER
• 金额: $ 105.91万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-25 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10357668
• 关键词: Amputation; Amputees; Ankle; Back; Bilateral; Biomimetics; Boston; Devices; Dorsal; Electric Stimulation; Electrodes; Equilibrium; Esthesia; Extensor; Feedback; Flexor; Frequencies; Gait; Heel; Home; Hybrids; Impairment; Implant; Individual; Intuition; Joints; Lateral; Leg; Limb Prosthesis; Limb structure; Location; Lower Extremity; Measures; Medial; Mediating; Modality; Modeling; Motor; Movement; Muscle; Musculoskeletal Equilibrium; Nerve; Participant; Pattern; Phantom Limb Pain; Phase; Play; Posture; Prosthesis; Psychophysics; Quality of life; Reflex action; Reporting; Role; Sensory; Signal Transduction; Spinal Cord; Spinal Ganglia; Spinal nerve root structure; Stimulus; Testing; Toes; Touch sensation; Training; Walking; clinically relevant; clinically significant; design; epidural space; experimental study; fall risk; improved; instrument; joint mobilization; limb amputation; limb movement; neuroprosthesis; pressure; prosthesis control; residual limb; response; restoration; sensor; sensory feedback; sensory input; spinal reflex

PROJECT SUMMARY / ABSTRACT Recent advances in design and actuation have led to important improvements in prosthetic limbs. However, these devices lack a means for providing direct sensory feedback, requiring users to infer information about limb state from pressure on the residual limb. Lack of sensation limits their ability to control the prosthesis and leads to slow gait and increased risk of falling. There is also evidence that lack of sensory feedback contributes to phantom limb pain (PLP), and that electrical stimulation at the dorsal root ganglia (DRG) can reduce PLP. The primary objective of this study is to use commercially available, FDA-cleared spinal cord stimulator (SCS) leads to test the effects of electrical stimulation of the DRG and dorsal rootlets (DR) as a means of restoring naturalistic sensation (e.g. pressure, movement), reducing PLP, and improving gait function in transtibial amputees. We will use stimulation to (1) produce sensations of pressure and joint movement, (2) reduce PLP, (3) evoke patterns of muscle activity that mimic automatic responses that occur normally during standing and walking, and (4) improve postural stability when standing and walking with a sensorized prosthesis. Aim 1: Use stimulation of the DRG/DR to generate naturalistic sensations of pressure and joint movement, localized to the amputated limb, and achieve a clinically relevant reduction in phantom limb pain To provide intuitive feedback, evoked sensations should be perceived as originating in the amputated limb and should feel naturalistic. A concomitant reduction in PLP may also have important effects on quality of life. We will perform detailed psychophysical testing in which stimulation parameters are varied while study participants are asked to report information about the evoked sensation (e.g. location, modality, naturalness) and the effects on PLP. Aim 2: Characterize the motor responses in the intact and amputated limbs evoked by DRG/DR stimulation and their relationship to stimulation parameters Bilaterally coordinated reflexes play an important role when responding to unexpected perturbations like slips and trips. Additionally, the transitions between phases of gait are largely mediated by reflexive responses to sensory input from the legs. For a prosthesis to restore the full capabilities of the amputated limb during standing and walking, the ability to evoke and precisely control these patterns of reflexive activity will be critical. We will record electromyogram (EMG) signals from the limbs during standing and walking while varying stimulus patterns and quantify the relationships between stimulation parameters and evoked reflexive responses. Understanding these relationships will aide in the programming of stimulation patterns for functional prosthesis use. Aim 3: Decrease postural sway and increase gait stability by providing sensory feedback via DRG/DR stimulation To quantify the functional impact of sensory restoration on prosthetic limb usage, we will instrument each participant's prosthetic limb with a pressure sensitive insole and joint angle sensors, and use signals from these devices to modulate stimulation. We will perform a battery of posture and balance measures, and we will track changes in functional prosthesis usage after a 7-day take-home trial of the device.

项目概要/摘要 设计和驱动方面的最新进展导致了假肢的重大改进。然而，这些设备 缺乏提供直接感觉反馈的方法，需要用户根据压力推断肢体状态信息 残肢。缺乏感觉限制了他们控制假肢的能力，导致步态缓慢并增加了受伤的风险 坠落。还有证据表明，缺乏感觉反馈会导致幻肢痛 (PLP)，而电刺激 刺激背根神经节 (DRG) 可以减少 PLP。本研究的主要目的是将 经 FDA 批准的脊髓刺激器 (SCS) 可用于测试 DRG 和电刺激的效果 背根 (DR) 作为恢复自然感觉（例如压力、运动）、减少 PLP 的手段，以及 改善经胫骨截肢者的步态功能。我们将使用刺激来（1）产生压力和关节的感觉 运动，(2) 减少 PLP，(3) 唤起模仿正常发生的自动反应的肌肉活动模式 站立和行走期间；(4) 使用传感假肢提高站立和行走时的姿势稳定性。 目标 1：利用 DRG/DR 的刺激来产生压力和关节运动的自然感觉， 定位于截肢，并实现临床相关的幻肢痛减轻 为了提供直观的反馈，诱发的感觉应该被认为起源于截肢，并且应该感觉 自然主义的。 PLP 的伴随减少也可能对生活质量产生重要影响。我们将进行详细的 心理物理测试，其中刺激参数变化，同时要求研究参与者报告信息 关于诱发的感觉（例如位置、形态、自然度）以及对 PLP 的影响。 目标 2：表征 DRG/DR 刺激引起的完整肢体和截肢肢体的运动反应 它们与刺激参数的关系 在应对滑倒和绊倒等意外扰动时，双边协调反射发挥着重要作用。 此外，步态阶段之间的转换很大程度上是通过对来自大脑的感觉输入的反射反应来介导的。 腿。对于要恢复截肢肢体在站立和行走过程中的全部功能的假肢来说， 唤起并精确控制这些反射活动模式将至关重要。我们会记录肌电图（EMG） 在站立和行走过程中变化刺激模式时来自四肢的信号并量化关系 刺激参数和诱发反射反应之间的关系。了解这些关系将有助于 对功能性假肢使用的刺激模式进行编程。 目标 3：通过 DRG/DR 刺激提供感觉反馈，减少姿势摇摆并提高步态稳定性 为了量化感觉恢复对假肢使用的功能影响，我们将测量每个参与者的 带有压力敏感鞋垫和关节角度传感器的假肢，并使用来自这些设备的信号进行调节 刺激。我们将执行一系列姿势和平衡测量，并且我们将跟踪功能的变化 将该设备带回家试用 7 天后假肢的使用情况。