On Determination of Spinal Stresses Generated While Performing Symmetrical and Asymmetrical Manual Lifting Tasks

Abstract

This paper describes the development, and subsequent use, of a three-dimensional kinetic biomechanical model for determining compressive and shear forces generated in the human spine during symmetric and asymmetric manual lifting tasks. Using the model, task variables such as couplings and box-size were investigated. Biomechanical analyses of data indicated that asymmetrical lifting, lifting larger boxes, or lifting boxes without handles is more stressful compared to symmetrical lifting, lifting compact boxes, or lifting boxes with handles.