Exoskeleton footwear to improve walking performance and subject-reported preference.

该项目的长期目标是改善外周动脉患者的生活质量 疾病(PAD)使用辅助外骨骼。PAD是系统性动脉粥样硬化的一种表现 显著减少流向四肢的血流量。患有PAD的退伍军人接受血管成形术， 近端搭桥和远端搭桥手术的发生率比普通美国男性高10倍。 血流量减少会导致行走过程中的疼痛，称为跛行。由此导致的跛行疼痛 与健康人相比，PAD导致患者行走更少、速度更慢，并失去独立性 对口单位。我们的研究已经确定了跛行患者行走模式的功能局限性， 其中最显著和一致的是小腿后肌，踝趾屈肌的缺陷，以 在行走过程中产生健康的脚踝扭矩和力量。一个设计得当的外骨骼将允许患者 使用PAD可以无痛步行更长时间，或以较小的压力完成日常活动所需的距离 到受影响的腿上。在对患有PAD的患者实施EF之前，必须改进设计以 提高步行能力和患者的实际使用。作为第一步，我们建议确定EF的效果 关于步行能力，重点是EF如何对生物踝关节扭矩和 动力、能量成本和小腿肌肉氧合。我们将对健康的老年人进行测试，以确保和确认 舒适，降低脚部和小腿受伤的风险，并培养患者采用设备的高潜力 带PAD的。然后对患有PAD的患者进行EF评估。健康的老年人被选为这一点 初始阶段，因为像PAD患者一样，他们在行走时产生的推力矩和功率较小 与健康的年轻人相比；使他们成为PAD局限性的合适模型。我们的具体目标是： 目标1：确定能产生更好行走效果的EF辅助力量水平 在年龄较大的受试者中的表现。 目标2：确定产生更好的受试者报告偏好的EF援助力量的水平 在较老的受试者中。 目的3：确定EF辅助水平对行走能力和受试者的影响 PAD患者的偏好。目标1和目标2的结果将指导为实现这一目标测试的援助水平。 将从内布拉斯加州招募50名健康的老年人参加AIMS 1和2，25名PAD患者参加AIMS 3 以及西部爱荷华州退伍军人事务部医疗中心和周围的奥马哈社区。AIM 1将测试 七种情况，包括五级EF辅助，EF没有弹簧和一次正常行走 条件。将使用步态生物力学测量腿部扭矩和功率。 每种情况下进行三分钟的跑步机运动。肌肉氧合将用近红外光谱分析来测量 小腿肌肉。新陈代谢车将被用来衡量能源成本。目标2将彻底评估 受试者报告的不同EF援助级别的偏好。视觉模拟标尺，感觉到的劳累比率 和疼痛，可行性访谈将提供舒适性、疲劳性和体力活动困难 主题以及EF的可接受性、要求和实用性。目标3将评估步行 性能、能量成本、肌肉氧合和受试者报告偏好的方式与 在目标1和目标2中提出，除了跑步机测试将执行最大步行距离测试 在两个不同的测试日。我们假设将有一个EF援助水平来满足受试者- 报告的偏好和步行性能目标。这项提议将提供必要的 将建立EF疗效并指导EF的说明性规范的基础知识 适用于PAD患者使用。

The long term goal of this project is to improve the quality of life of patients with peripheral artery disease (PAD) using assistive exoskeletons. PAD is a manifestation of systemic atherosclerosis that significantly reduces blood flow to the lower extremities. Veterans with PAD undergo angioplasty, proximal bypass, and distal bypass procedures at rates 10 times higher than the general US male population. Reduced blood flow leads to pain during walking known as claudication. Claudication pain that results from PAD causes patients to walk less and slower, and lose independence compared with their healthy counterparts. Our research has identified functional limitations in the walking patterns of claudicating patients, the most prominent and consistent of which is a deficit of the psterior calf muscles, the ankle plantarflexors, to generate healthy ankle toruqe and power during walking. A properly designed exoskeleton will allow patients with PAD to walk longer without pain or walk the distance needed for completing daily activities with less stress to the affected leg. Before EF can be implemented in patients with PAD, the design must be improved to increase walking performance and actual patient use. As a first step we propose to determine the effect of EF on walking performance, focusing on the how EF contributes to changes in the biological ankle torque and power, energy cost, and calf muscle oxygenation. We will test healthy older adults to ensure and confirm comfort, decrease risk of injury to the foot and calf, and cultivate high potential for device adoption in patients with PAD. The EF will then be evaluated in patients with PAD. Healthy older individuals are selected for this initial phase because like patients with PAD, they produce less push-off torque and power during walking compared with healthy young; making them an appropriate model for PAD limitations. Our specific aims are: Aim 1: To determine the levels of EF assistance force level which produce better walking performance in older subjects. Aim 2: To determine the levels of EF assistance force which produce better subject-reported preference in older subjects. Aim 3: To determine the effect of EF assistance levels on walking performance and subject-reported preference in patients with PAD. Aims 1 and 2 results will guide the assistance levels tested in this aim. 50 healthy older adults for Aims 1 and 2, and 25 patients with PAD for Aim 3 will be recruited from the Nebraska and Western Iowa Veterans Affairs’ Medical Center and surrounding Omaha community. Aim 1 will test seven conditions, including five levels of EF assistance, the EF with no spring and one normal walking condition. Lower extremity torque and power will be measured using gait biomechanics on the treadmill for three minutes per condition. Muscle oxygenation will be measured with near infrared spectroscopy of the calf muscles. A metabolic cart will be used to measure energy cost. Aim 2 will thoroughly assess subject-reported preference across levels of EF assistance. Visual analog scales, rate of perceived exertion and pain, and feasibility interviews will provide the comfort and fit, fatigue, and physical activity difficulty of subjects along with the acceptability, demand, and practicality of the EF. Aim 3 will assess walking performance, energy cost, muscle oxygenation, and subject reported preference in the same manner as proposed in Aims 1 and 2, except the treadmill tests will be maximal walking distance tests performed across two difference testing days. We hypothesize there will be an EF assistance level to satisfy subject- reported preference and walking performance goals. This proposal will provide essential fundamental knowledge that will establish EF efficacy and guide prescriptive specifications for EF to be adopted for use by patients with PAD.