The assessment of material handling strategies in dealing with sudden loading: the effects of load handling position on trunk biomechanics.
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.
Department of Industrial and Management Systems Engineering, West Virginia University, Morgantown, WV 26506, USA. Electronic address: xiaopeng.ning@mail.wvu.edu.
Xiaopeng
X
Ning
Department of Industrial and Management Systems Engineering, West Virginia University, Morgantown, WV 26506, USA. Electronic address: jizhou@mix.wvu.edu.
Jie
J
Zhou
Division of Kinesiology and Health, University of Wyoming, Laramie, WY 82071, USA. Electronic address: bdai@uwyo.edu.
Boyi
B
Dai
Department of Industrial and Management Systems Engineering, West Virginia University, Morgantown, WV 26506, USA. Electronic address: majid.jaridi@mail.wvu.edu.
Majid
M
Jaridi
D019567:Back Injuries / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D004576:Electromyography; D006801:Humans; D017770:Lifting; D008297:Male; D011187:Posture / Q000502:physiology*; D013131:Spine / Q000502:physiology*; D013909:Thorax / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology; D014903:West Virginia; D055815:Young Adult
Back injury; Load handling position; Sudden loading