Identification of Persistent Impairments in Postural Control Following Concussion

描述（由申请人提供）：脑震荡，每年影响160 - 380万美国人，可造成潜在的严重后果，包括第二次冲击综合征，死亡率为50%，在短期内和慢性创伤性脑病，肌萎缩侧索硬化症，轻度认知障碍，临床诊断的抑郁症，以及长期潜在的早期阿尔茨海默病的风险增加。虽然目前用于识别脑震荡存在的评估技术近年来取得了实质性进展，但评估方案在做出重返赛场的决定时通常没有用处，这在很大程度上是由于实践影响和对细微损伤的低灵敏度。具体来说，姿势控制是利用平衡误差评分系统（BESS）来评估的，然而，这个测试在评分者之间和评分者内部的可靠性都很低，并且受到实践效果的影响。因此，迫切需要开发一种客观的方法来识别脑震荡后姿势控制中关键的、微妙的、挥之不去的损伤，并为临床医生开发一种实用的持续评估方法。步态起始（GI）、步态和步态终止（GT）的生物力学评估为识别各种平衡受损群体的姿势不稳定性提供了一种客观的方法。此外，二次认知任务的增加挑战了个体脑震荡后有限的功能储备。因此，本建议的一般假设是，单任务和双任务GI、步态和GT将单独和共同识别脑震荡后姿势稳定性的损害，并且这些损害将在个体恢复到传统的脑震荡恢复临床测量基线后持续存在；症状缓解，BESS和神经心理表现。我们的假设将通过两个特定目标进行验证：1)确定是否可以通过单任务和双任务GI、步态和GT来识别脑震荡后的姿势稳定性损伤；2)将G、步态和GT的表现与国际推荐的方案进行比较，以评估恢复情况。36名患有急性脑震荡的受试者将从脑震荡后的第二天开始每天接受测试，直到他们恢复参与，并将与36名未脑震荡的受试者配对。主要结局指标；压力中心位移和速度，运动的时空参数和地面反作用力将在使用生存分析的受试者内部和之间进行比较。根据我们的初步数据，我们假设GI、步态和GT将识别出姿势稳定性的损害，这些损害将持续到BESS评估的基线。这些发现，如果客观地记录下来，将证明目前对姿势稳定性的临床评估是不足的，并将提供一种新的、临床实用的方法来识别脑震荡后动态姿势稳定性的持续性损伤。

DESCRIPTION (provided by applicant): Concussions, affecting 1.6 - 3.8 million Americans annually, can pose potentially serious consequences including second impact syndrome, with a 50% mortality rate, in the short term and elevated risk of chronic traumatic encephalopathy, amyotrophic lateral sclerosis, mild cognitive impairment, clinically diagnosed depression, and a potentially earlier onset of Alzheimer disease in the long term. While current assessment techniques for identifying the presence of a concussion has made substantial progress in recent years, the assessment protocols are typically not useful in making return to participation decisions due, in large part, to practice effects and low sensitivity to subtle impairments. Specifically, postural control is assessed utilizing the Balance Error Scoring System (BESS), however this test is has low inter- and intra-rater reliability and is subject to a practice effect. Therefore, a pressing need exists to develop an objective method to identify critical subtle, lingering impairments in postural control following a concussion and to develop a practical method of ongoing assessment for clinicians. Biomechanical assessment of gait initiation (GI), gait, and gait termination (GT) provides an objective method of identifying postural instabilities in a wide range of balance impaired groups. Further, the addition a secondary cognitive task challenges the limited functional reserves of the individual post-concussion. Therefore, the general hypothesis of this proposal is that single and dual-task GI, gait, and GT will individually and collectively identify impairments in postural stability following a concussion and these impairments will persist after the individual has returned to baseline on traditional clinical measures of concussion recovery; symptom resolution, BESS, and neuropsychological performance. Our hypothesis will be tested by 2 specific aims: 1) determine if impairments in postural stability following a concussion can be identified through single and dual task GI, gait, and GT, and 2) to compare the performance of G, gait, and GT to internationally recommended protocols to assess recovery. Thirty-six subjects with acute concussions will be tested daily from the day after their concussion until they return to participation and will be matched with thirty- six non-concussed subjects. The primary outcome measures; center of pressure displacements and velocity, spatiotemporal parameters of locomotion, and ground reaction forces will be compared both within and between subjects utilizing survival analysis. We hypothesize, supported by our preliminary data, that GI, gait, and GT will identify impairments in postural stability and these impairments will persist beyond return to baseline of the BESS assessment. These findings, if objectively documented, would demonstrate that current clinical assessments of postural stability are insufficient and will provide a new, clinically practical method of identifying persistent impairments in dynamic postural stability following a concussion. PUBLIC HEALTH RELEVANCE: Premature return to participation following a concussion leads to elevated risk of both repeat concussions and the potential for long term risk of brain damage; thus, accurate and timely concussion assessment and reassessment is a vital component of making medically correct decisions on return to participation. This project aims to improve the current standards of ongoing concussion assessment by identifying lingering and persistent subtle impairments in postural control and thus providing clinicians with an additional set of tools to assist in ongoing recovery assessment. The results of this project support the NIH's stated mission of extending the healthy life by potentially reducing premature return to participation and therefore limiting the risks of the potentially fatal second impact syndrome as well as repeat concussions and their associated life-long consequences.