Biomechanical Effects of Industrial Eccentric Exertions

工业偏心运动的生物力学效应

• 批准号: 6662663
• 负责人: ROBERT G RADWIN
• 金额: $ 18.06万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-30 至 2005-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6662663
• 关键词: arm; biomechanics; blood chemistry; clinical research; creatine kinase; ergonomics; human subject; industry; magnetic resonance imaging; mechanical pressure; muscle stress; musculoskeletal disorder; neuromuscular disorder; occupational hazard; occupational health /safety; occupational psychology; occupations; pain; repetitive motion injury; tendon injury; work site

DESCRIPTION: This research studies the effects of repetitive eccentric exertions in industrial power hand tool operation on biomechanical properties of muscle and tendon in order to better understand the etiology and prevention of work related musculoskeletal disorders. It is hypothesized that increased power tool reaction force and build-up time corresponds with greater changes in the dymanic characteristics of the upper limb. A laboratory-based experiment will define the short-term relationship between repetitive eccentric exertions (i.e. reaction force magnitude and build-up time) and upper limb properties (i.e. stiffness, viscous damping and inertial mass). Subjects will repetitively resist forearm supination against a motor for simulating eccentric exertion levels representative of pistol grip power hand tool operation. Peak torque levels and build-up time will be experimentally controlled. Forearm mechanical properties will be measured before and following a period of work. Mechanical parameters will be ascertained using a unique apparatus that models the forearm as a single degree-of-freedom dynamic mechanical system by measuring the angular displacement of a disturbance to a known mechanical system in free oscillation when the subject uses maximal effort to oppose its motion. Our preliminary data reveals that significant stiffness and inertial mass changes are observed when exercising eccentrically at similar intensity levels. Biochemical measures of blood creatine kinase (CK), and anatomical measures using T2 changes in an MRI of the forearms will be compared with biomechanical parameters prior to, and following repetitive eccentric exertions for a random subset of the subjects. Subjective discomfort will be assessed using a visual analog scale, and forearm edema and strength will also be measured. The second experiment will assess similar upper limb biomechanical properties for industrial workers who regularly perform repetitive eccentric exertions of varying intensity, build-up time and repetition rate in selected industrial jobs. Subjects will be recruited from tool operation jobs on a local automobile assembly line. This research can ultimately lead to better ergonomic interventions through quantitative power hand tool design guidelines and work practices based on understanding the damaging effects of exposure to specific levels of reaction force, build-up time and repetition, as well as providing new outcome measures for epidemiological studies.

描述：本研究研究了重复的偏心量在工业动力手动工具操作中对肌肉和肌腱生物力学特性的影响，以便更好地了解与工作相关的肌肉骨骼疾病的病因和预防。假设增加的功率工具反作用力和堆积时间与上肢的染色体特征发生了更大的变化。一个基于实验室的实验将定义重复的偏心劳动（即反作用力幅度和堆积时间）与上肢特性（即刚度，粘性，粘性阻尼和惯性质量）之间的短期关系。受试者将重复抵抗前臂旋转对电动机的旋转，以模拟代表手枪握把动力手动工具操作的偏心劳动水平。峰值扭矩水平和堆积时间将受到实验控制。在工作期间之前和之后，将测量前臂机械性能。将使用独特的设备来确定机械参数，该设备通过测量对自由振荡的已知机械系统的角度位移来对其进行自由振荡时的角度位移来模拟前臂作为单个自由度的动态机械系统。我们的初步数据表明，在以相似的强度水平进行偏心运动时，观察到显着的刚度和惯性质量变化。血液肌酸激酶（CK）的生化测量方法以及使用前臂MRI的T2变化的解剖学测量将与对受试者随机子集的重复性偏心劳累之前的生物力学参数进行比较。将使用视觉模拟量表评估主观不适，并且还将测量前臂水肿和强度。第二个实验将评估与经常在某些工业工作中进行不同强度，积累时间和重复率不同的偏心繁殖的工业工人的类似上肢生物力学特性。将从本地汽车装配线上的工具操作工作中招募对象。这项研究最终可以通过理解暴露于特定水平的反作用力，积累时间和重复以及为流行病学研究提供新的结果指标的损害影响，通过了解暴露于特定水平的反作用力，积累时间和重复的损害影响，从而为更好的人体工程学干预。