SPASTICITY: MECHANISMS AND QUANTIFICATION

痉挛：机制和量化

• 批准号: 3399378
• 负责人: WILLIAM Zev RYMER
• 金额: $ 15.08万
• 依托单位: REHABILITATION INSTITUTE OF CHICAGO D/B/A SHIRLEY RYAN ABILITYLAB
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-04-01 至 1990-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3399378
• 关键词: biomechanics; cutaneous sensory nerve; elbow; electromyography; human subject; hypertonia; innervation; motor neurons; muscle contraction; muscle tension; neural recruitment; neuromuscular disorder diagnosis; neuromuscular transmission; spastic paralysis; stretch reflex; viscosity

We plan to study two different aspects of the disturbance in movement associated with spastic hemiparesis. Our subject group will consist largely of stroke and head trauma victims. First, stretch reflex dynamics and alterations in mechanical properties of elbow muscles and related soft-tissues will be estimated from the EMG and torqued responses elicited by a variety of perturbations, including pseudorandom binary pulse (PRBS) and sinusoidal perturbations of elbow joint angle. We anticipate that these measurements will reveal no systematic modification of reflex dynamics in spastic limb (as compared with the contralateral side) and that increases in measured torque will result from alterations in viscoelastic properties of muscle and of other elbow soft tissues. Second, the nature and origins of the disturbance in muscle synergy that accompanies spastic hemiparesis will be evaluated, using simultaneous intramuscular EMG recordings from most of the significant elbow muscles during precisely regulated isometric contractions of elbow musculature. Synergic relations will be characterized by plots of EMG in one muscle against EMG in a synergist, for a constant torque direction, over increasing torque magnitudes. Major disruptions of synergic relations which are insensitive to voluntary control or to alterations in the limb mechanical load will indicate that new sources of motoneuron innervation have developed. This finding may, in turn, indicate the deelopment of new connections to motoneurons or simply the preferential use of preexisting but less appropriate pathways. Understanding the characteristics and origins of disturbances in synergy is of great potential significance in understanding the origin of motor dysfunction in hemiparesis, and it will also help define potential mechanisms of functional recovery.

我们计划研究运动干扰的两个不同方面 与痉挛性偏瘫有关。 我们的主题组将组成 主要是中风和头部创伤受害者。 首先，拉伸反射动力和机械性能的改变 肘部肌肉和相关的软组织将从EMG和 各种扰动引起的扭曲响应，包括 肘部二元脉冲（PRB）和肘正弦扰动 关节角度。 我们预计这些测量结果将揭示 痉挛性肢体中反射动力学的系统修改（比较 与对侧侧），并增加测得的扭矩将会 肌肉和其他其他的粘弹性特性的改变产生 肘部软组织。 其次，肌肉协同作用的障碍的性质和起源 伴随痉挛性偏瘫，将同时评估 来自大多数重要肘部肌肉的肌内EMG记录 在精确调节肘部肌肉的等距收缩期间。 协同关系将以EMG在一个肌肉中的图为特征 在协同作用中反对EMG，以持续的扭矩方向 增加扭矩幅度。 协同关系的重大破坏 对自愿控制或肢体的改变不敏感 机械负载将表明运动神经支配的新来源 已经开发了。 反过来，这一发现可能表明了新的 与运动神经元的连接或仅优先使用先前存在 但不太合适的途径。 了解协同作用中干扰的特征和起源是 在理解电动机的起源方面具有巨大的潜在意义 偏瘫的功能障碍，也将有助于定义潜力 功能恢复的机制。