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

项目摘要 急救人员、军事和执法人员经常背负高达60%的身体重量 重量。在载重过程中或之后经常需要使用手和手指，但载重 通过背包背带使用，可以收缩血液流动，压迫上臂丛神经。 四肢。这些因素可能会导致疼痛、受伤和上肢功能受损。了解 大负重负重对上肢生理的急性影响将有助于场基功能的发展 减少受伤风险和防止手功能长期丧失的措施。经常携带 用于职业目的的沉重的背包负荷报告了背包麻痹的发生率，这是一种导致缺乏 感觉和虚弱在手中。拟议的工作旨在调查两国之间的关系 生理变化，搬运过程中的手动功能障碍，以及背部瘫痪。目前还不清楚这是如何 背包搬运的大小和持续时间会影响握力、握力、手动 灵巧和轻触的感官阈值。总的假设是背着背包走路会 导致上肢血流、浮肿和神经传导的改变。此外，我们预计这些生理上的 变化将导致手动灵活性、强度和轻触感觉阈值的可测量差异 这会随着背包中负重的增加和负重行走的持续时间而改变。要解决这个问题 假设，我将确定上肢血流、浮肿和神经传导的相对急性变化 背着沉重的背包走路前后。我还将确定血流的数量变化，握力 在15%和30%体重负荷水平下的力量、握力和手动灵巧性 控制条件。我将探索背包负重步行时间对上肢血流和体重的影响 触摸手指的感觉阈值，这可能会受到背包背带上的神经压迫的影响。 这项亟需的研究将提高对上肢生理和神经肌肉的理解。 与背包托架一起变化。这种创新的方法将允许对多个上肢进行研究 生理变化同时发生。增加对背包运输的理解可以改善 预防臂丛神经损伤，从而减少虚弱或手功能丧失的发生率。 这项工作的应用可能导致臂丛神经压迫的早期诊断。 措施。这项工作的结果可能会改善手的功能，预防和治疗上肢 对于那些在职业或娱乐环境中背负沉重背包的人来说，这是一种极端的选择。

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.