Corticospinal Efficacy as a Prognostic Indicator for Walking Recovery Post-stroke

 描述（由申请人提供）： 中风是全世界成年人严重慢性残疾的主要原因。美国每年发生超过 750,000 例首次中风病例，占所有急性神经系统住院病例的一半以上。虽然三分之二的中风患者恢复了行走能力，但由此产生的步态模式缓慢、不对称且代谢效率低下。步行功能障碍是中风后最大的身体限制之一，而改善步行是神经康复最常见的目标之一。迄今为止，中风后步行功能障碍的康复已经产生了高度可变的结果，显示步行功能（包括步行速度或模式）的真正变化很小。我们的长期目标是改善中风后的行走能力。该提案的目的是研究中风后运动恢复能力的神经生理学机制。具体来说，我们的目标是确定神经生理学措施，以区分接受或不接受治疗干预的中风幸存者。我们假设，在功能低下的中风幸存者中，下降运动束对远端腿部肌肉（足底和背屈肌）的功效大大降低，而在功能较高的个体中，这种功效至少部分保留。该项目的第一个目标是根据行走过程中在远端腿部肌肉中观察到的可区分运动诱发电位 (MEP) 的比例来区分高功能和低功能中风幸存者。我们预计，与功能较高的个人相比，功能较低的个人中可区分的欧洲议会议员的比例会较小。在该项目的第二个目标中，我们将评估这种关系 远端腿的皮质运动功能与行走过程中的生物力学功能之间的关系。我们的初步数据表明皮质脊髓功能与行走过程中产生的力之间存在联系。具体来说，我们预计整个步态周期的 MEP 调节与步行过程中踝关节跖屈肌发电相关。在该提案的第三个目标中，我们将评估皮质脊髓功效是否可以预测干预后步行功能的改善。利用我们之前工作中开发的有效干预措施，我们将进行一项力量训练研究，以对干预前的皮质脊髓功效测量与干预后的步行功能增益进行试点比较。我们预计，皮质脊髓功效较高的个体在干预后的步态速度和运动功能方面将表现出最大的改善。这项研究的结果将通过提供个人中风后恢复行走功能的能力的预后指标来填补当前知识的空白。此外，从这项研究中获得的见解可用于制定有针对性的康复策略，以最大限度地实现神经康复。

 DESCRIPTION (provided by applicant): Stroke is the leading cause of serious, chronic disability in adults worldwide. Over 750,000 cases of first- ever stroke occur in the United States each year accounting for over half of all acute neurological hospital admissions. While two-thirds of persons who suffer a stroke regain the ability to walk, the resulting gait pattern is slow, asymmetrical and metabolically inefficient Walking dysfunction represents one of the greatest physical limitations post-stroke and improved walking is among the most frequently articulated goals of neurorehabilitation. To date, rehabilitation for walking dysfunction post-stroke has produced highly variable outcomes revealing minimal genuine change in walking function including walking speed or pattern. Our long-term goal is to improve walking post-stroke. The objective of this proposal is to investigate the neurophysiological mechanisms that underlie the capacity for locomotor recovery post-stroke. Specifically, our aim is to identify neurophysiologic measures differentiating stroke survivors who do or do not to a therapeutic intervention. We postulate that the efficacy of descending motor tracts to the distal leg muscles (plantar and dorsiflexors) is greatly reduced in low functioning stroke survivors, while this efficacy is at least partially preserved in higher functioning individuals. The first aim of this project seeks to differentiate high and low functioning stroke survivors based upon the proportion of distinguishable motor evoked potentials (MEPs) observed in the distal leg muscles during walking. We anticipate lower functioning individuals will have a smaller percentage of distinguishable MEPs compared to higher functioning individuals. In the second aim of this project we will evaluate the relationship between corticomotor function in the distal leg and biomechanical function during walking. Our preliminary data suggest a link between the corticospinal function and force production during walking. Specifically, we expect MEP modulation across the gait cycle correlates with ankle plantarflexor power generation during walking. In the third aim of the proposal we will evaluate whether corticospinal efficacy can predict post-intervention improvements in walking function. Using an efficacious intervention developed in our previous work, we will conduct a study of power training to pilot comparisons of pre-intervention measures of corticospinal efficacy with post-intervention gains in walking function. We anticipate that individuals with higher corticospinal efficacy will show the largest improvements in gait speed and locomotor function post-intervention. The results of this study will fill a gap in current knowledge by providing a prognostic indicator of an individual's capacity to recover walking function post-stroke. Furthermore, insights gained from this study can be used to develop targeted rehabilitation strategies to maximize neurorehabilitation.