Neuropathic Gait, Irregular Surfaces and Fall Risk

描述（由申请人提供）：糖尿病周围神经病变（DPN）在美国老年人中越来越常见，患病率接近15%，是福尔斯的潜在危险因素。以往的研究表明，老年人DPN有功能上的显着损害，下肢感觉和运动功能，影响姿势控制。不规则的表面，挑战姿势控制，是这个人群中常见的福尔斯原因。此外，在不规则表面上测量步态变异性比在光滑表面上测量步态变异性更有效地区分患有DPN的老年人和没有DPN的老年人，以及摔倒的DPN老年人和没有摔倒的老年人。我们假设，踝关节力输出的反馈回路延迟响应于扰动，主要与DPN相关的强度产生率的损害有关，是DPN导致姿势不稳定的机制，这反过来又导致步态变异性增加和跌倒风险。因此本研究的目的是：1）测量40名受试者踝关节力输出的反馈回路延迟（30名DPN，按严重程度分层，10名健康老年人），并使用运动学和测力板数据确定其预测对由新型鞋提供的离散扰动的姿势反应的能力，在内侧和外侧前足下; 2）利用相同的受试者，通过确定其预测在光滑和不规则表面上的步态变异性的测量的能力，进一步评估反馈回路延迟的影响; 3）为了研究在光滑和不规则表面上分别确定的步态变异性的测量的程度，预测在一组100名DPN受试者中前瞻性观察一年以上的福尔斯和跌倒相关损伤的发生率。由此产生的研究将深入了解DPN损害从表面不规则性恢复的机制，并确定最能预测这一高危人群中福尔斯和跌倒相关损伤的步态测量。公共卫生相关性散步作为一种运动形式，是成人发病糖尿病的常见和重要治疗方法。然而，许多老年糖尿病患者的脚和腿有神经损伤，导致他们跌倒，特别是在不规则的表面上行走时。这项研究将确定这些患者跌倒的原因，以及哪些患者跌倒和受伤的风险最大。这些信息将导致使这些患者在行走时更安全的策略。

DESCRIPTION (provided by applicant): Diabetic peripheral neuropathy (DPN) is increasingly common among older Americans, with a prevalence approaching 15%, and is a potent risk factor for falls. Previous work has shown that older persons with DPN have functionally significant impairments in lower extremity sensory and motor function that impacts postural control. An irregular surface, which challenges postural control, is a common source of falls in this population. Moreover, measures of gait variability on an irregular surface more effectively differentiate between older persons with DPN and those without, and between older persons with DPN who fall and those who do not, than similar measures on a smooth surface. We hypothesize that feedback loop delay in ankle joint force output in response to a perturbation, related primarily to a DPN-associated impairment in rate of strength generation, is the mechanism by which DPN leads to postural instability, which in turn results in increased gait variability and fall risk. Therefore the aims of this research are: 1) To measure feedback loop delay in ankle joint force output in a group of 40 subjects (30 DPN, stratified by severity, and 10 healthy old) and determine its ability to predict postural responses to discrete perturbations, provided by a novel shoe, under the medial and lateral forefoot using kinematic and force plate data; 2) To further evaluate the effect of feedback loop delay, utilizing the same subjects, by determining its ability to predict measures of gait variability on smooth and irregular surfaces; 3) To investigate the extent to which measures of gait variability, determined separately on smooth and irregular surfaces, predict the incidence of falls and fall-related injuries observed prospectively over one year in a group of 100 subjects with DPN. The resulting research will provide insights into the mechanism by which DPN impairs recovery from surface irregularities and identify the gait measure best able to predict falls and fall-related injuries in this high risk population. PUBLIC HEALTH RELEVANCE Walking as a form of exercise is a common and important treatment of adult onset diabetes mellitus. However, many older patients with diabetes have nerve damage in their feet and legs that causes them to fall, particularly when walking on irregular surfaces. This research will identify the reasons that such patients fall, and which patients are at greatest risk of falling and being injured. This information will lead to strategies for making such patient safer while walking.