Ning Xiaopeng, Zhou Jie, Dai Boyi, Jaridi Majid
Department of Industrial and Management Systems Engineering, West Virginia University, Morgantown, WV 26506, USA.
Division of Kinesiology and Health, University of Wyoming, Laramie, WY 82071, USA.
Appl Ergon. 2014 Nov;45(6):1399-405. doi: 10.1016/j.apergo.2014.03.008. Epub 2014 Apr 22.
Back injury caused by sudden loading is a significant risk among workers that perform manual handling tasks. The present study investigated the effects of load handling position on trunk biomechanics (flexion angle, L5/S1 joint moment and compression force) during sudden loading. Eleven subjects were exposed to a 6.8 kg sudden loading while standing upright, facing forward and holding load at three different vertical heights in the sagittal plane or 45° left to the sagittal plane (created by arm rotation). Results showed that the increase of load holding height significantly elevated the peak L5/S1 joint compression force and reduced the magnitude of trunk flexion. Further, experiencing sudden loading from an asymmetric direction resulted in significantly smaller peak L5/S1 joint compression force, trunk flexion angle and L5/S1 joint moment than a symmetric posture. These findings suggest that handling loads in a lower position could work as a protective strategy during sudden loading.
在从事体力搬运任务的工人中，突然加载导致的背部损伤是一个重大风险。本研究调查了突然加载过程中负载搬运位置对躯干生物力学（屈曲角度、L5/S1关节力矩和压缩力）的影响。11名受试者在直立、面向前方并在矢状面或矢状面左侧45°（通过手臂旋转形成）的三个不同垂直高度持握负载时，承受6.8千克的突然加载。结果表明，负载持握高度的增加显著提高了L5/S1关节压缩力峰值，并减小了躯干屈曲幅度。此外，与对称姿势相比，从不对称方向承受突然加载导致L5/S1关节压缩力峰值、躯干屈曲角度和L5/S1关节力矩显著更小。这些发现表明，在较低位置搬运负载可能是突然加载期间的一种保护策略。
