A framework for feasible translation to enhance foot and ankle function in aging and mobility

一个可行的翻译框架，以增强足部和脚踝在衰老和活动中的功能

• 批准号: 10501648
• 负责人: Jason R Franz
• 金额: $ 56.07万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10501648
• 关键词: Address; Affect; Age; Aging; Ankle; Benchmarking; Bioenergetics; Biomechanics; Clinical; Clinical Management; Consumption; Data; Devices; Distal; Elastic Tissue; Elasticity; Elderly; Exhibits; Foot joint structure; Gait; Generations; Human; Impairment; Institution; Intramuscular; Locomotion; Measurable; Measurement; Mechanics; Metabolic; Metatarsal bone structure; Modeling; Modification; Motor Activity; Muscle; Outcome; Output; Performance; Phase; Play; Public Health; Quality of life; Regulation; Research; Research Infrastructure; Research Personnel; Role; Self-Help Devices; Series; Shoes; Speed; Structure; System; Testing; Tissue imaging; Translations; Ultrasonography; Walking; Work; achilles tendon; age effect; age related; aging population; ankle joint; aponeurosis; carbon fiber; cost; cost effective; design; efficacy testing; electromyographic biofeedback; foot; functional disability; improved; improved mobility; in vivo; insight; joint function; mechanical energy; muscle strength; negative affect; novel; peer; response; strength training; transmission process; young adult

PROJECT SUMMARY This proposal will address the critical need for new and modifiable targets to enhance mobility and restore independence to those in our rapidly aging population. Due to reduced ankle push-off power, older adults walk slower and with higher metabolic energy cost than younger adults. As our central premise, we contend that hallmark age-associated deficits in push-off intensity during walking have been far too often mistakenly attributed solely to the plantarflexor muscles, and instead originate interdependently with those in the active, passive, and structural regulation of foot mechanical power. This premise paves the way for translational opportunities to augment foot structure and function to enhance independence and quality of life. This study combines the research agendas of two highly productive investigators and leverages the research infrastructure of two peer institutions. Aim 1 will be the first to study mechanical power interactions between the human foot and ankle in governing reduced push-off intensity and walking economy in older adults across a wide variety of everyday walking tasks. By combining metabolic measurements with state-of-the-art biomechanical and bioenergetic modeling, we will test the hypothesis that older adults exhibit higher mechanical energy losses via foot structures than young adults – aging effects that: (i) are larger for walking tasks that increase foot demand, (ii) misappropriate ankle moment and power during push-off, and thereby (iii) correlate with shorter 6 min walk distance and increased metabolic energy cost compared to young adults. Aim 2 will provide mechanistic insight into aging effects on the active, passive, and structural regulation of foot-ankle mechanical power interactions during walking. Using a series of controlled loading paradigms on a dynamometer combined with advanced in vivo ultrasound imaging and novel electromyographic biofeedback, we will test the hypotheses that older adults exhibit: (i) reduced foot and plantarflexor muscle strength and (ii) lower structural stiffness of and (iii) reduced structural connectivity between series elastic tissues spanning the foot and ankle – changes that require elevated plantar intrinsic muscle activation to maintain requisite foot stiffness and associate with reduced ankle moment and power output during push-off in walking. Finally, as a translational benchmark, Aim 3 will show that shoe- stiffness modifications that act in parallel with the plantar aponeurosis and intrinsic muscles can mitigate age- associated deficits in push-off function during walking. Supported by promising pilot data, we will test the hypotheses that older adults walking with increased shoe insole stiffness will exhibit: (i) smaller mechanical energy losses at the foot, (ii) more favorable plantarflexor muscle contractile dynamics, (iii) greater peak ankle moment and power output, and thus (iv) longer 6 min walk distance and reduced whole-body metabolic energy cost. Ultimately, this work will establish a paradigm shift in our biomechanical understanding and clinical management of age-related mobility impairment toward feasible and cost-effective devices to modify foot-ankle function – an outcome with significant potential to enhance independence and quality of life for millions.

项目概要 该提案将解决对新的和可修改的目标的迫切需求，以增强流动性和恢复 由于脚踝的推力减弱，老年人无法独立行走。 作为我们的中心前提，我们认为比年轻人更慢并且代谢能量成本更高。 步行过程中与年龄相关的推离强度的标志性缺陷经常被错误地对待 仅归因于跖屈肌，而是与活跃的肌肉相互依赖地起源， 这一前提为脚部机械动力的被动和结构调节铺平了道路。 这项研究有机会增强足部结构和功能，以提高独立性和生活质量。 结合了两位高产研究人员的研究议程并利用研究基础设施 两个同行机构的目标 1 将是第一个研究人足之间机械动力相互作用的机构。 和脚踝在控制各种老年人的减少推离强度和步行经济性方面 通过将代谢测量与最先进的生物力学和 生物能模型，我们将通过以下方式测试老年人表现出更高机械能损失的假设 足部结构比年轻人强——衰老效应：(i) 对于增加足部需求的步行任务来说更大， (ii) 蹬地时脚踝力矩和力量不当，从而 (iii) 与较短的 6 分钟步行时间相关 与年轻人相比，距离和代谢能量消耗增加将提供机制洞察。 研究衰老对足踝机械动力相互作用的主动、被动和结构调节的影响 在步行过程中，在测力计上使用一系列受控加载范例，并结合先进的技术。 体内超声成像和新颖的肌电生物反馈，我们将测试老年人的假设 表现出：(i) 足部和跖屈肌强度降低，(ii) 结构刚度降低，(iii) 降低 跨越足部和踝部的一系列弹性组织之间的结构连接——需要升高的变化 足底内在肌肉激活，以维持必要的足部硬度并减少踝关节力矩 最后，作为平移基准，Aim 3 将显示鞋子- 与足底腱膜和内肌并行作用的硬度改变可以减轻年龄- 在有希望的试点数据的支持下，我们将测试步行期间推离功能的相关缺陷。 假设老年人行走时鞋垫硬度增加会表现出：（i）较小的机械性能 足部的能量损失，(ii) 更有利的跖屈肌收缩动力学，(iii) 更大的踝峰峰值 力矩和功率输出，因此 (iv) 6 分钟步行距离更长，全身代谢能量减少 最终，这项工作将在我们的生物力学理解和临床方面建立范式转变。 管理与年龄相关的行动障碍，寻找可行且具有成本效益的设备来修改足踝 功能——具有增强数百万人独立性和生活质量的巨大潜力的成果。