Muscle coordination changes affecting impaired balance control post-stroke.

肌肉协调变化影响中风后平衡控制受损。

• 批准号: 9114874
• 负责人: Jessica Allen
• 金额: $ 5.8万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9114874
• 关键词: Adult; Affect; Ankle; Ataxia; Automobile Driving; Biomechanics; Clinical; Coupled; Coupling; Data; Development; Elderly; Electric Stimulation; Electromyography; Equilibrium; Exhibits; Gait; Goals; Hip region structure; Impairment; Individual; Intervention; Knee; Knowledge; Lead; Leg; Limb structure; Lower Extremity; Measurable; Measures; Motor; Movement; Muscle; Output; Paresis; Pattern; Performance; Population; Proxy; Quality of life; Recruitment Activity; Rehabilitation therapy; Research; Specificity; Speed; Stroke; Surface; Task Performances; Time; Translations; Walking; base; equilibration disorder; fall risk; functional disability; gait rehabilitation; gait retraining; improved; improved outcome; leg paresis; neuromuscular; novel; post stroke; programs; public health relevance; rehabilitation paradigm; response; restoration; stroke hemiparesis

 DESCRIPTION (provided by applicant): The long-term goal of this research is improve quality of life post-stroke by improving the development and prescription of rehabilitation efforts. This proposal is focused on gaining fundamental knowledge about neuromuscular mechanisms that impair gait and balance post-stroke and lead to increased risk of falls and decreased mobility. This is important because rehabilitation paradigms for retraining gait and balance have been limited by a lack of understanding of the underlying neuromuscular mechanisms leading to functional impairments. Therefore, this project will examine how muscle coordination is impaired across both walking and balance post-stroke. Further, we will also examine how muscle coordination is changed after a successful gait rehabilitation program. In Aim 1, we will identify and compare impairments in muscle coordination during balance and gait in individuals post-stroke. In Aim 2, we will examine mechanisms of improved muscle coordination through a novel gait rehabilitation program. We will record muscle activity using electromyography (EMG) while walking at self-selected speed and during reactive balance (responses to support-surface translations while standing). We will characterize muscle coordination using motor modules, which identify groups of muscles that are activated together. A reduction has been shown post-stroke in the number of motor modules in the paretic leg during gait that is related to lower scores on clinical measures of both gait and balance. In many of these individuals, the reduced number of motor modules was due to abnormal coupling of the ankle plantarflexors with the hip and knee extensors. Even in those individuals without this abnormal coupling, recruitment of the ankle plantarflexors were often inappropriately timed. We do not know if this inappropriate timing or abnormal coupling also occurs during balance. We expect that the number, composition and timing of motor modules on the paretic leg will be altered due to abnormal muscle coupling and inappropriate recruitment timing in both gait and balance. We will also take advantage of an ongoing rehabilitation program as a platform to understand how neuromuscular mechanisms underlying the control of balance and gait can be improved. This rehabilitation program targets improving ankle muscle recruitment through functional electrical stimulation and has been shown to improve biomechanical and clinical measures of gait and balance performance. However, muscle activity has yet to be examined and thus it is unknown if these improvements are related to restoration of appropriate ankle activity and/or whole-limb muscle coordination. We expect that this rehabilitation program restores appropriate whole-limb muscle coordination during both gait and balance. The results of the proposed project will help us to understand how abnormal muscle coupling and inappropriate recruitment timing leads to functional impairments in gait and balance post- stroke and will contribute to the understanding of how rehabilitation ameliorates these functional impairments, driving the improvement and specificity of such interventions to improve outcomes and quality of life.

 描述（由申请人提供）：本研究的长期目标是通过改进康复工作的开发和处方来提高中风后的生活质量。该提案的重点是获得有关神经肌肉机制的基础知识，这些机制会损害中风后的步态和平衡，并导致跌倒风险增加和活动能力下降。这很重要，因为重新训练步态和平衡的康复模式因缺乏对导致功能障碍的潜在神经肌肉机制的了解而受到限制。因此，该项目将研究中风后步行和平衡方面的肌肉协调性如何受损。此外，我们还将研究成功的步态康复计划后肌肉协调性如何改变。在目标 1 中，我们将识别并比较中风后个体在平衡和步态过程中肌肉协调的损伤。在目标 2 中，我们将研究通过新颖的步态康复计划改善肌肉协调的机制。我们将使用肌电图 (EMG) 记录以自选速度行走时和反应平衡期间（站立时对支撑表面平移的反应）期间的肌肉活动。我们将使用运动模块来描述肌肉协调性，该模块识别一起激活的肌肉群。中风后，步态期间瘫痪腿的运动模块数量减少，这与步态和平衡的临床测量得分较低有关。在许多这样的人中，运动模块数量的减少是由于踝关节跖屈肌与髋关节和膝关节伸肌的异常耦合所致。即使在那些没有这种异常耦合的个体中，踝关节跖屈肌的募集也常常不合适的时机。我们不知道这种不恰当的时机或异常耦合是否也会在平衡过程中发生。我们预计，由于步态和平衡方面的异常肌肉耦合和不适当的募集时间，瘫痪腿上运动模块的数量、组成和时间将发生改变。我们还将利用正在进行的康复计划作为平台，了解如何改善控制平衡和步态的神经肌肉机制。该康复计划的目标是通过功能性电刺激改善踝关节肌肉募集，并已被证明可以改善步态和平衡表现的生物力学和临床测量。然而，肌肉活动仍有待检查，因此尚不清楚这些改善是否与恢复适当的脚踝活动和/或全肢肌肉协调有关。我们期望该康复计划能够在步态和平衡过程中恢复适当的全肢肌肉协调性。拟议项目的结果将帮助我们了解异常的肌肉耦合和不适当的募集时间如何导致中风后步态和平衡的功能障碍，并将有助于了解康复如何改善这些功能障碍，推动此类干预措施的改进和特异性，以改善结果和生活质量。