Variability in Muscle Activity and Wrist Motion Measurements Among Workers Performing Non-Cyclic Work
Variability in Muscle Activity and Wrist Motion Measurements Among Workers Performing Non-Cyclic Work
复制标题
DOI：
10.1080/15459624.2012.634361
复制
发表时间：
2012-01-01
影响因子：
2
通讯作者：
Quickel, Mark T.
中科院分区：
文献类型：
--
作者：
Fethke, Nathan B.;Gerr, Fred;Quickel, Mark T.
用于估计物理风险因素暴露的适当抽样策略需要了解暴露随时间变化的情况。关于上肢肌肉骨骼疾病的身体危险因素暴露的可变性，特别是在非周期性工作活动期间，可获得的信息有限。我们调查了办公室、保管或维护人员中几个方差来源对总暴露方差的大小和相对贡献（每组 N = 5）。此外，我们还检查了每组工人内暴露的同质性以及工人组之间的暴露对比。通过表面肌电图（EMG）评估桡侧腕屈肌和上斜方肌群的激活，并通过电测角法评估手腕运动。在整个工作班次中两次连续收集暴露信息。我们观察到，对于所有肌电图和电测角仪汇总测量，当日受试者内方差分量对总暴露方差有很大贡献。我们还在上斜方肌肌电图的总结测量和大多数电测角测量总结测量中观察到职业组之间有限的暴露对比。受试者内日内较大差异表明，在未来对暴露于身体危险因素与上肢肌肉骨骼疾病之间的关联进行流行病学调查时，需要延长测量持续时间（例如超过 1 小时）。
Appropriate sampling strategies for estimation of exposure to physical risk factors require knowledge of exposure variability over time. Limited information is available about the variability of exposure to physical risk factors for upper extremity musculoskeletal disorders, especially during non-cyclic work activities. We investigated the magnitude and relative contributions of several sources of variance to the total exposure variance among office, custodial, or maintenance workers (N = 5 per group). In addition, we examined the homogeneity of exposure within each group of workers and exposure contrast between groups of workers. Activation of the flexor carpi radialis and upper trapezius muscle groups was assessed with surface electromyography (EMG) and wrist motion was assessed with electrogoniometry. Exposure information was collected continuously over a complete work shift on two occasions. We observed a substantial contribution of the within-day-within-subject variance component to the total exposure variance for all EMG and electrogoniometer summary measures. We also observed limited exposure contrast between the occupational groups in summary measures of upper trapezius EMG and most electrogoniometry summary, measures. The large within-day-within-subject variance suggests the need for prolonged measurement durations (e.g., more than 1 hr) in future epidemiologic investigations of associations between exposure to physical risk factors and upper extremity musculoskeletal disorders.