title: The assessment of material handling strategies in dealing with sudden loading: influences of foot placement on trunk biomechanics.
abstract: Sudden unexpected loading has been identified as a risk factor of work-related low back pain (LBP). This study investigated the effects of different foot placements and load-releasing locations on trunk biomechanics under an unexpected sudden loading event. Fifteen subjects experienced sudden release of a 6.8-kg external load from symmetric or asymmetric directions while maintaining four different foot placements. The results showed that subjects experienced on average 4.1° less trunk flexion, 6.6 Nm less L5/S1 joint moment and 32.0 N less shear force with staggered stance with the right foot forward (the most preferred placement) compared with wide stance (the least preferred placement). Asymmetric load-releasing positions consistently resulted in smaller impacts on trunk biomechanics than symmetric positions. The findings suggest that staggered stance and asymmetric load-holding position can be used as a protective load-handling posture against LBP caused by sudden loading.
  In a work environment, unexpected sudden loading may cause low back pain (LBP). In this study, we used empirical data to demonstrate how different foot placements and load-releasing locations can be used to mitigate the impact of sudden loading on the spine and to reduce the risk of LBP.
authors.affiliation: a The Ergonomics Lab, Department of Industrial and Management Systems Engineering, West Virginia University , P.O. Box 6070, Morgantown , WV 26506 , USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.forename: Boyi
authors.initials: B
authors.lastname: Dai
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Ning
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005528:Foot / Q000502:physiology*; D006801:Humans; D017770:Lifting; D008161:Lumbosacral Region; D008297:Male; D011187:Posture; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult; D021801:Zygapophyseal Joint / Q000502:physiology*