Degeneration of motoneurons caudal to spinal lesion

项目摘要 拟议项目的长期目标是了解脊髓的复杂起源。 损伤(SCI)导致肌肉麻痹、萎缩、虚弱和肌肉痉挛，这些通常导致有限的 关节运动范围和肌肉内在力学特性的渐进性变化。尤其是，我们的 提出的研究计划依赖于最近发展的几种新的表面肌电(EMG)技术 探讨脊髓损伤后尾侧运动神经元变性的争议概念。使用马达 单元号指数测量和高密度表面肌电记录和处理技术，我们将 确定瘫痪肌肉的运动单位结构和功能是否可能由于尾部而发生变化 运动神经元变性，可以通过三个特定的目标来捕捉。也就是说，我们计划评估是否有 运动单位数目的估计是脊髓损伤的运动神经元变性的证据 瘫痪肌肉(目标1)，并使用记录的静息瘫痪肌肉的自发肌电活动 (目标2)。此外，我们将研究运动单位动作电位传播模式的变化和 神经支配带作为瘫痪后运动神经元丢失和随后的肌纤维再支配的标志 肌肉，因此提供了脊髓损伤的运动神经元变性的次要证据(目标3)。这个 研究中使用的方法是非侵入性的，潜在的使用方便，并提供有价值的信息。 超过了针基肌电和其他常规电生理学方法所提供的。调查结果来自 这些新的方法将加强我们对潜在运动神经元的病理生理学的理解。 脊髓损伤退行性变。这将为制定康复战略和设备提供指导 恢复正常的肌肉功能。这项研究的发现也具有重要的临床价值。 脊柱损伤的诊断和治疗，改善预后测量，并帮助评估 药物或疗法。

Project Abstract The long-term goals of the proposed project are to understand the complicated origins of the spinal cord injury (SCI) induced muscle paresis, atrophy, weakness, and muscle contractures that often result in a limited range of joint motion and progressive changes in intrinsic muscle mechanical properties. In particular, our proposed research plan relies on several recently developed novel surface electromygram (EMG) techniques to investigate controversial concepts about caudal motoneuron degeneration after a spinal injury. Using motor unit number index measurements and high-density surface EMG recording and processing techniques, we will determine whether motor unit structure and function changes of paralyzed muscles, potentially due to caudal motoneuron degeneration, can be captured via three specific aims. Namely, we plan to assess whether there is evidence for motoneuron degeneration caudal to spinal injury using estimates of motor unit numbers in paralyzed muscles (Aim 1), and using the recorded spontaneous EMG activities in resting paralyzed muscles (Aim 2). In addition, we will examine alterations in motor unit action potential propagation patterns and innervation zones, as a marker of motoneuron loss and subsequent muscle fiber reinnervation in paralyzed muscles, thus providing secondary evidence for motoneuron degeneration caudal to spinal injury (Aim 3). The methods used in this study are noninvasive, potentially convenient to use, and offer valuable information beyond that provided by needle-based EMG and other routine electrophysiological methods. The findings from these novel methods will enhance our understanding of the pathophysiology of potential motoneuron degeneration in SCI. This will provide guidance for the development of rehabilitation strategies and devices for restoration of normal muscle functions. The findings from this study also have important clinical value for the diagnosis and treatment of spinal injury, improve outcome measurements, and help evaluate the effects of medication or therapies.