The effect of different surfaces on biomechanical loading of shoulder and lumbar spine during pushing and pulling of two-wheeled containers.
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.
Laursen
Bjarne
B
National Institute of Public Health, Copenhagen, Denmark.
Schibye
Bente
B
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*