title: The effect of different surfaces on biomechanical loading of shoulder and lumbar spine during pushing and pulling of two-wheeled containers.
abstract: Seven waste collectors pushed and pulled a two-wheeled container on three different surfaces: flagstones, paving stones, grass. Net torques at the shoulder joint and the lumbar spine as well as the compression and shear forces in the lumbar spine at the L4/L5 level were calculated for the tilting, initial and sustained phases. The lumbar spine compression force was below 1800N and the shear force was below 200 N in all situations. The shoulder torque when pulling with one hand was up to 80 N m. The container weight affected the magnitude of the push/pull forces and the load on the shoulders but not the load on the lumbar spine. The type of surface affected the magnitude of the push/pull forces during initial and sustained phases, and affected the load on the shoulder in the sustained phase. However, it did not affect the compression in the lumbar spine.
authors: National Institute of Public Health, Copenhagen, Denmark.
authors: Bjarne
authors: B
authors: Laursen
authors: Bente
authors: B
authors: Schibye
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology; D009140:Musculoskeletal Diseases / Q000517:prevention & control*; D009784:Occupational Diseases / Q000517:prevention & control*; D012785:Shoulder Joint / Q000502:physiology*; D013499:Surface Properties; D013647:Task Performance and Analysis; D014743:Videotape Recording; D016474:Weight-Bearing / Q000502:physiology*