Exploring the Neuromechanics of Fall-Risk in Aging

描述（由申请人提供）：福尔斯是65岁及以上人群受伤死亡的主要原因，在美国，至少95%的老年人髋部骨折是由跌倒引起的。随着老年人口（>65岁）与美国人口不成比例地增长，跌倒相关伤害的治疗和康复费用将给美国经济带来不可持续的负担。尽管美国国立卫生研究院的大量和持续的资金被分配给跌倒相关的研究，老年人遭受的福尔斯的数量继续增加，可能是由于这种资金流的重点是自愿恢复运动的生物力学。随着年龄的增长，自愿的恢复运动并不足够快，实际上无法防止跌倒的发生。虽然知识基础是丰富的生物力学的福尔斯，一个相当大的知识差距存在关于神经力学的跌倒风险在老化。了解到反射系统是唯一能够快速反应以防止跌倒的系统，我们开发了测试老年人防止福尔斯跌倒的“第一道防线”的创新方法。通过检查老化对反射的影响，即神经运动系统的第一反应者，我们将深入了解导致老年人跌倒风险更大的下降。我们的具体目标是比较：（1）交叉脊髓反射（翻正反应的关键组成部分）的年龄差异;（2）反射扰动后的姿势恢复;（3）反射功能与临床评估的跌倒风险之间的关系。我们预计，老年人将表现出减少对称性之间的交叉脊髓反射与不直接的姿势恢复时，扰动。这些姿势恢复和交叉脊髓反射的缺陷预计与更大的跌倒风险相关。反射缺陷的识别将导致一个重大的科学突破，产生更敏感的跌倒风险筛查程序。此外，大量的研究表明，反射是可训练的，反射再训练有可能作为现有神经肌肉康复方法的补充。 公共卫生相关性：疾病预防控制中心报告说，跌倒相关的伤害是65岁及以上人群死亡的主要原因，这个年龄组在美国正成为比例最大的年龄组。尽管福尔斯摔倒的速度对于自愿反应来说太快了，但身体的“第一反应者”，即反射系统的功能下降还是未知的。这些发现与公共卫生有关，因为人类的反射可以（重新）训练，为老年人预防跌倒提供了新的途径。

DESCRIPTION (provided by applicant): Falls are the leading cause of injury death in people aged 65 and older and cause at least 95% of the hip fractures in older adults in the US. With the elderly population (>65 year-olds) growing out of proportion to the US population, the costs of treatment and rehabilitation of fall-related injuries will place an unsustainable burden on the US economy. Despite a significant and sustained amount of NIH funding being allocated toward fall-related studies, the number of falls suffered by older persons continues to increase, likely due to the emphasis of this funding stream on the biomechanics of voluntary recovery movements. Voluntary recovery movements, with advanced age, are not quick enough to actually prevent a fall from occurring. While the knowledge base is plentiful in the biomechanics of falls, a sizeable knowledge gap exists regarding the neuromechanics of fall-risk in aging. Knowing that the reflex system is the only system that can respond quickly enough to prevent a fall, we have developed innovative methods of testing the "first line of defense" against falls in the elderly. By examining the effects of aging on reflexes, that is, the neuromotor system's first responders, we will gain insight into the declines that lead to greater fall risk in the elderly. Our specific aims are to compare: (1) age differences in crossed-spinal reflexes, a critical component of the righting response; and (2) postural recovery following a reflex perturbation; and (3) the relation between reflex function and clinically assessed fall-risk. We expect that the elderly will exhibit reduced symmetry between their crossed-spinal reflexes with a less direct postural recovery when perturbed. These deficits in postural recovery and crossed-spinal reflexes are expected to correlate with greater fall-risk. The identification of reflex deficits will lead to a significant scientific breakthrough by yielding more sensitive fall-risk screening procedures. Furthermore, the sizeable body of research that has shown that reflexes are trainable holds the potential for reflex re-training as a complement to existing methods of neuromuscular rehabilitation. PUBLIC HEALTH RELEVANCE: The CDC reports that fall-related injuries are the leading cause of death in individuals aged 65 years and older, an age group that is becoming proportionally the largest in America. Even though falls happen at a rate that is often too fast for a voluntary response, the functional decline in the body's "first responders," the reflex system, is unknown. These findings are relevant to public health in that human reflexes can be (re-)trained, providing a new avenue for fall-prevention in the elderly.