Effect of Heavy Backpack Load Carriage on Acute Blood Flow, Nerve Conduction, Biomechanics and Dexterity of the Upper Limbs

项目摘要 第一反应，军事和执法人员经常携带高达60%的身体背包负荷 重量.在承载期间或承载之后，经常需要使用手和手指，但 通过背包带施加可以收缩血流并压迫上肢的臂丛神经 四肢这些因素可能会导致疼痛、受伤和上肢功能受损。了解 负重对上肢生理的急性影响将有助于基于场的功能的发展， 减少受伤风险和防止手部功能长期丧失的措施。经常携带 为职业目的而背负沉重的背包报告了背包麻痹的发生率，这种残疾导致缺乏 手的感觉和无力。拟议的工作旨在调查之间的关系 生理变化、搬运背包时的手功能缺陷和背包麻痹。目前尚不清楚， 背包携带的幅度和持续时间影响握力、捏力、手动 灵活性和轻触感觉阈值。总的假设是，背着背包走路， 引起上肢血流、水肿和神经传导的变化。此外，我们预计这些生理 变化将导致手的灵活性、力量和轻触感觉阈值的可测量的差异 这将随着背包中的负荷的增加和负重行走的持续时间而改变。解决 假设，我将确定上肢血流量，水肿和神经传导的相对急性变化 在背着沉重的背包行走前后。我还将确定血流的定量变化，抓地力 在15%和30%体重的负荷水平下， 控制条件我将探讨步行时间与背包负荷对上肢血流量和光的影响 手指的触觉阈值可能会受到背包带压迫神经的影响。 这项急需的研究将提高对上肢生理和神经肌肉的理解， 与背包车厢的变化。创新的方法将允许研究多个上肢 生理变化同时进行。增加对背包运输的了解可以提高 预防臂丛神经损伤，从而减少手部无力或功能丧失的发生率。 本研究的应用有助于臂丛神经卡压症的早期诊断 措施这项工作的结果可能会改善手功能，预防损伤，并治疗上肢 对于那些在职业或娱乐环境中携带沉重背包的人来说，

Project Summary First responder, military, and law enforcement personnel regularly carry backpack loads of up to 60% body weight. Use of the hands and fingers is often needed during or immediately after load carriage, but loads applied via backpack straps can constrict blood flow and compress the brachial plexus nerves of the upper limb. These factors can potentially lead to pain, injury and impaired use of the upper limbs. Understanding the acute effects of heavy load carriage on upper limb physiology will aid development of field-based functional measures to reduce the risk of injury and prevent long-term loss of hand function. Persons who regularly carry heavy backpack loads for occupational purposes report incidences of pack palsy, a disability causing lack of sensation and weakness in the hands. The proposed work aims to investigate relationships among physiological changes, manual functional deficits during pack carriage, and pack palsy. It is unclear how the magnitude and duration of backpack carriage affects acute changes in grip strength, pinch strength, manual dexterity and light touch sensory threshold. The overall hypothesis is that walking with backpack load will cause changes in upper limb blood flow, edema, and nerve conduction. Further, we expect these physiological changes will result in measurable differences in manual dexterity, strength, and light touch sensory threshold that will change with increasing load in the backpack and duration of time walking with load. To address the hypotheses, I will determine the relative acute changes in upper limb blood flow, edema and nerve conduction before and after walking with heavy backpack load. I will also identify quantitative changes in blood flow, grip strength, pinch strength and manual dexterity at load levels of 15% and 30% body weight as compared to a control condition. I will explore the effects of walking time with backpack load on upper limb blood flow and light touch sensory threshold of the fingers which may be affected by nerve compression from backpack straps. This much needed research will improve understanding of upper limb physiological and neuromuscular changes with backpack carriage. The innovative methodology will allow study of multiple upper limb physiological changes simultaneously. Increased understanding of backpack carriage could improve prevention of brachial plexus injury and therefore reduce incidences of weakness or loss of hand function. Application of this work could lead to early diagnosis of brachial plexus compression by means of functional measures. Results of this work may improve hand function, injury prevention, and treatment of the upper extremity for those who carry heavy backpacks in an occupational or recreational setting.