Leveraging energetics to improve gait rehabilitation after stroke

项目摘要 步态障碍是出了名的难以康复，尽管最近取得了进展，我们缺乏有效的治疗 许多临床人群的选择。在这里我们提出的实验将建立一种新的思维方式 关于中风后的步态康复不是训练病人执行特定的行走模式 重复（如常规治疗中经常做的那样），我们建议康复应旨在使 理想的步行模式消耗较少的能量，因为人们自然喜欢最小化能量的步行模式 成本考虑到这一点，我们将进行一系列实验，证明中风后的人 1)能够操纵他们的行走模式的对称性，以及2）如果新的步态模式 模式消耗更少的能量。这些介绍性的研究将为步态设计奠定重要的基础 康复干预的重点是降低所需步态模式的能量成本。 在目标1中，我们将研究中风后改变步态对称性的能力。很多人发- 在日常生活中不对称步行。我们设计了一个视觉反馈系统 向参与者显示他们在任一步位置方面行走的对称程度（即，脚在哪里 放置在全局空间中）或步长（即，一只脚在另一只脚之前有多远）。我们假设 中风后的人将能够使用视觉反馈来改善他们在两个步骤位置的步态对称性 和步长，揭示了中风后的人比他们更能保持对称行走的能力 在日常生活中这就引出了一个我们将在目标2中讨论的重要问题--中风后患者是否可以行走 为什么他们更喜欢不对称的行走模式？ 在目标2中，我们将研究能量消耗如何影响中风后行走。中风后的人经常走路 具有不对称的步数，并且步行的能量消耗相对于健康成年人升高。但据 中风后的人可能更喜欢不对称地行走，因为对称的步伐甚至更 考虑到影响许多患者的单侧运动缺陷，我们将评估速度和不对称性 通过让参与者以不同的速度行走来影响中风后患者行走的能量消耗， 利用视觉反馈来操纵它们的不对称性。我们假设中风后的人 体验到对称行走带来的能量效益。然后，我们将使用一种新颖的跑步机控制器， 创造一个对称行走比不对称行走消耗更少能量的环境。我们假设 中风后的人在这种环境中行走会更对称，这表明中风后的人 如果康复可以减少对称行走的能量消耗，则可以自然地更对称地行走。 总的来说，这项建议将建立中风后的人可以操纵他们的步态对称性， 改变他们走路的方式以最大限度地减少能源消耗。这些发现将为建立新的 康复干预措施通过重塑充满活力的景观来改善患者的步态模式。

Project Summary Gait dysfunction is notoriously difficult to rehabilitate and, despite recent advances, we lack effective treatment options for many clinical populations. Here we propose experiments that will establish a new way of thinking about gait rehabilitation after stroke. Instead of training a patient to perform a particular walking pattern repetitively (as is often done in conventional therapy), we suggest that rehabilitation should aim to make the desired walking pattern cost less energy because people naturally prefer walking patterns that minimize energy cost. With this in mind, we will execute a series of experiments that demonstrate that persons post-stroke are 1) capable of manipulating the symmetry of their walking patterns, and 2) adopt new gait patterns if the new patterns cost less energy. These introductory studies will lay an important foundation for designing gait rehabilitation interventions focused on decreasing the energy cost of desired gait patterns. In Aim 1, we will investigate the capacity for persons post-stroke to change gait symmetry. Many persons post- stroke walk with asymmetric steps in daily life. We have designed a visual feedback system where we can show participants how symmetrically they are walking in terms of either step position (i.e., where the feet are placed in global space) or step length (i.e., how far one foot is placed ahead of the other). We hypothesize that persons post-stroke will be able to use the visual feedback to improve their gait symmetry in both step position and step length, revealing that persons post-stroke retain the capacity to walk more symmetrically than they do in daily life. This leads to an important question that we will address in Aim 2 – if persons post-stroke can walk more symmetrically, why do they prefer asymmetric walking patterns? In Aim 2, we will investigate how energy cost influences walking after stroke. Persons post-stroke often walk with asymmetric steps and the energy cost of walking is elevated relative to healthy adults. However, it is possible that persons post-stroke prefer to walk asymmetrically because symmetric stepping is even more effortful given the unilateral motor deficits that affect many patients. We will assess how speed and asymmetry affect the energy cost of walking in persons post-stroke by having participants walk at different speeds and manipulate their asymmetry using visual feedback. We hypothesize that persons post-stroke will not experience any energetic benefit from walking symmetrically. We will then use a novel treadmill controller to create an environment where symmetric walking costs less energy than asymmetric walking. We hypothesize that persons post-stroke will walk more symmetrically in this environment, revealing that persons post-stroke may naturally walk more symmetrically if rehabilitation can reduce the energy cost of symmetric walking. Overall, this proposal will establish that persons post-stroke can manipulate their gait symmetry and will change how they walk to minimize energy cost. These findings will establish a foundation for building new rehabilitation interventions that drive improvements in patient gait patterns by reshaping energetic landscapes.