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: 10612265
• 负责人: LEE E FISHER
• 金额: $ 7.07万
• 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 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10612265
• 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.

项目摘要 /摘要 设计和致动的最新进展导致了假肢的重要改善。但是，这些设备 缺乏提供直接感官反馈的方法，要求用户从压力上推断出有关肢体状态的信息 残留的肢体。缺乏感觉限制了他们控制假体的能力并导致步态缓慢，并增加了风险 跌倒。也有证据表明，缺乏感觉反馈会导致幻影肢体疼痛（PLP），并且电气 背根神经节（DRG）的刺激可以减少PLP。这项研究的主要目的是在商业上使用 可用的，FDA清除的脊髓刺激剂（SC）会导致测试DRG的电刺激的影响 背根（DR）是恢复自然主义感觉（例如压力，运动），减少PLP的一种手段 改善跨态截肢者中的步态功能。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）引起肌肉活动的模式，模仿正常发生的自动反应 在站立和步行期间，以及（4）用传感器的假体站立和行走时提高姿势稳定性。 目标1：使用刺激DRG/DR来产生自然主义的压力和关节运动， 位于截肢的肢体上，并实现临床相关的幻影肢体疼痛 为了提供直观的反馈，应将诱发的感觉视为起源于截肢的肢体，应该感觉到 自然主义。 PLP的伴随减少也可能对生活质量产生重要影响。我们将执行详细 心理物理测试，其中刺激参数变化时，研究参与者被要求报告信息 关于诱发的感觉（例如位置，模态，自然性）和对PLP的影响。 AIM 2：表征由DRG/DR刺激和 它们与刺激参数的关系 在响应诸如滑移和旅行之类的意外扰动时，双侧协调的反射起着重要作用。 此外，步态阶段之间的转变主要是通过对感官输入的反射反应介导的 腿。为了使假肢在站立和行走过程中恢复截肢的肢体的全部能力， 唤起并精确控制这些反身活性模式将是至关重要的。我们将记录肌电图（EMG） 站立和行走期间，来自四肢的信号，同时改变刺激模式并量化关系 在刺激参数和诱发的反射反应之间。了解这些关系将有助于 用于功能假体的刺激模式的编程。 目标3：通过通过DRG/DR刺激提供感觉反馈来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，我们将仪器仪器 具有压力敏感鞋垫和关节角传感器的假肢肢体，并使用这些设备的信号调节 刺激。我们将执行一系列的姿势和平衡措施，我们将跟踪功能的变化 对该设备进行了为期7天的带回家试验后的假体使用情况。