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.

项目摘要 该建议将满足对新目标的关键需求，以增强移动性和恢复 对我们迅速老龄化的人的独立性。由于脚踝推断降低，老年人走路 比年轻人慢，代谢能量成本更高。作为我们的中心前提，我们认为 在步行期间，标志性年龄相关的推断强度的防御能力频繁地错误地被误认为 仅归因于足底肌肉，而是与活动中的肌肉相互依存， 被动和脚的结构调节。这个前提为翻译铺平了道路 增强脚结构和功能以增强独立性和生活质量的机会。这项研究 结合了两个高产研究人员的研究议程，并利用了研究基础设施 两个同行机构。 AIM 1将是第一个研究人脚之间机械功率相互作用的人 以及管理降低的推断强度和步行经济的脚踝，老年人在各种各样的地方 日常行走任务。通过将代谢测量与最先进的生物力学相结合 生物能建模，我们将检验以下假设：老年人通过 脚结构比年轻人 - 衰老的影响：（i）对于增加脚步需求的步行任务更大， （ii）推开期间误导的脚踝时刻和力量，从而（iii）与短步行6分钟相关 与年轻人相比，距离和代谢能量成本增加。 AIM 2将提供机械洞察力 对脚部机械功率相互作用的主动，被动和结构调节的衰老影响 在步行期间。在测功机上使用一系列受控的加载范例与高级 体内超声成像和新型肌电图生物反馈，我们将测试老年人的假设 暴露：（i）脚和足底肌肉力量减小，以及（ii）降低的结构刚度和（iii）降低 横跨脚和踝关节的串联弹性组织之间的结构连通性 - 需要升高的变化 足底固有的肌肉激活以保持必要的脚部刚度，并与脚踝降低相关 和在行走时推开期间的功率输出。最后，作为转化基准，AIM 3将表明鞋子 - 与足底肌病和内在肌肉并行作用的刚度修饰可以减轻年龄 关联在步行过程中定义推断功能。在有希望的飞行员数据的支持下，我们将测试 假设老年人以增加鞋底鞋垫僵硬而行走的老年人将存在：（i）较小的机械 脚部的能量损失，（ii）更有利的足底肌肉收缩动力学，（iii）大峰踝 力矩和功率输出，因此（iv）更长的6分钟步行距离和减少全身代谢能量 成本。最终，这项工作将在我们的生物力学理解和临床上建立范式转变 管理与年龄相关的行动不便障碍对可行且具有成本效益的设备，以修改脚部 功能 - 具有巨大潜力增强独立性和生活质量的巨大潜力的结果。