Active and passive gait perturbation systems to improve fall risk assessment

描述（由申请人提供）： 背景/依据：福尔斯是老年人中的一个重要问题，在65岁以上的人中，几乎一半的伤害相关死亡是由跌倒造成的。许多临床筛查测试可以预测跌倒风险，但这些测试都没有纳入或评估可能引发大多数福尔斯的步态扰动的反应。在临床实践中，福尔斯史是未来福尔斯的最佳预测因子之一，并且是跌倒减少干预研究的金标准结局。然而，自我报告可能会低估实际的福尔斯，并没有考虑到风险暴露，这可能会对跌倒的可能性产生重大影响。此外，自我报告和相对不频繁的福尔斯的问题需要大样本量来检测干预措施对跌倒风险的显著降低。长时间跟踪这些大样本导致每次研究的成本很高，因此可以资助评估减少跌倒干预措施的研究较少。福尔斯已经在受控的实验室环境中安全地诱导，每次使用一个扰动，但受试者不可避免地适应 他们的步态模式，以尽量减少他们的风险，从特定的扰动使用。具体的适应因扰动类型而异，但都偏离了习惯的步态模式，降低了结果的生态有效性。在一次测试过程中，各种类型的步态扰动的可能性可以减少或消除这些适应，从而提高实验室诱导的跌倒恢复研究的生态有效性。目标-这个为期三年的实验室研究的目标如下：发展：设计和构建主动和被动步态扰动系统。 测试：验证安全性、可行性和有效性 主动和被动步态扰动系统和测试协议，然后完成人体受试者测试。 分析：完成数据处理和分析，测试假设，并为未来的研究制定新的假设。研究方法：这项基于开发实验室的研究将分三个阶段完成：开发阶段将包括主动和被动步态扰动系统的设计、构建、调试和迭代。活动表面将由五个嵌入实验室地板的离散扰动系统组成。这将评价受试者从即将发生的福尔斯跌倒中恢复的能力。被动表面将是一个4 m x 0.5m的人行道，由夹在两层低绒地毯之间的软泡沫层中的小木制障碍物组成。这将评估受试者在人行道表面受到微小的不可见偏差时保持一致步态模式和速度的能力。只有当这些系统的安全性（始终佩戴安全带）和有效性得到令人满意的确定后，人类受试者测试才开始。测试阶段将开始，测试10名未受损的年轻受试者，以微调程序并验证安全性，然后继续评估60名老年受试者- 30名非跌倒者（是的未跌倒）和30名跌倒者（过去6个月内跌倒）。分析阶段包括使用Visual 3D进行生物力学数据分析和使用SAS进行统计分析。 公共卫生相关性： 本研究通过开发更好的结果来评估旨在降低跌倒风险的干预措施，解决了RR&D研究的优先事项，即最大限度地恢复功能和恢复功能。通过减少所需的受试者数量和所需的随访时间，本研究应该可以在相同的资金下在更短的时间内进行更多的研究。从而最终促进老年退伍军人的功能独立性和安全移动性，并改善有福尔斯和跌倒相关损伤风险的退伍军人对衰老的成功适应和生活质量。此外，这项研究是一个很好的适合与国际移民组织的国家优先事项aras的预防福尔斯和最大限度地提高功能和使命的坦帕HSR&D/RR&D卓越中心在最大限度地提高康复效果。

DESCRIPTION (provided by applicant): Background/ Rationale: Falls are a significant problem in the older population and are responsible for nearly half of all injury-related deaths in persons over the age of 65. Many clinical screening tests can predict fall risk, but none of these tests incorporate or assess responses to gait perturbations that are likely to initiate most falls. A history of falls is one o the best predictors of future falls in clinical practice and is the gold-standard outcome for research studies of fall- reduction interventions. However, self-report may underestimate actual falls and does not account for exposure to risk, which could have substantial effects on the likelihood of falling. Furthermore, issues with self-report and the relative infrequency of falls necessitates large sample sizes to detect significant reductions in fall risk from interventions. Following thes large samples over a long period of time results in high costs per study and thus fewer studies that can be funded to evaluate fall-reduction interventions. Falls have been safely induced in controlled laboratory settings using a single perturbation at a time, but subjects inevitably adapt their gait pattern to minimize their risk from the particular perturbation used. The specific adaptations vary by perturbation type, but all are departures from habitual gait patterns that reduce the ecological validity of the results. The possibility of various types of gait perturbatio during a single testing session could reduce or eliminate these adaptations and thus improve the ecological validity of laboratory-induced fall recovery studies. Objectives- The objectives of this three-year, laboratory-based study are as follows: Development: Design and construct active and passive gait perturbation systems. Testing: Verify safety, feasibility, and efficacy of active and passive gait perturbation systems and testing protocols and then complete human subjects testing. Analyisis: Complete data processing and analysis, test hypotheses, and formulate new hypotheses for future research. Methods: This developmental laboratory-based study will be completed in three phases: The Development Phase will consist of the design, construction, debugging, and iteration of the active and passive gait perturbation systems. The active surface will consist of five discrete perturbation systems embedded into the laboratory flooring. This will evaluate the subject's ability to recover from impending falls. The passive surface will be a 4m x 0.5m walkway consisting of small wooden obstacles in a layer of soft foam sandwiched between two layers of low-pile carpet. This will assess the subject's ability to maintain a consistent gait pattern and speed when subjected to small unseen deviations in the walkway surface. Only when safety (a safety harness will be worn at all times) and effectiveness of these systems have been satisfactorily established will human subjects testing begin. The Testing Phase will begin by testing 10 unimpaired young subjects to fine-tune procedures and verify safety, then move on to evaluating 60 older subjects- 30 non-fallers (not fallen in last yea) and 30 fallers (fallen within the last 6 months).. The Analysis Phase of will consist of will consit of biomechanical data analysis using Visual3D and statistical analysis using SAS. PUBLIC HEALTH RELEVANCE: This study addresses the RR&D research priorities of maximizing functional recovery and restoring function by developing better outcomes to evaluate interventions intended to reduce fall risk. By reducing the number of subjects required and the required follow- up duration, this study should allow more studies to be conducted in less time with the same funds. Thus ultimately promoting functional independence and safe mobility of aging veterans and improve successful adaptation to aging and quality of life in veterans who are at risk for falls and fall-related injuries. Additionally, this research is an excellent fit with the IOM national priority aras of preventing falls and maximizing function and the mission of the Tampa HSR&D/RR&D Center of Excellence in Maximizing Rehabilitation Outcomes.