Trunk movements and load support strategy in simulated handling tasks carried out by workers with and without musculoskeletal symptoms.

Abstract

To compare two groups of worker with and without upper limb musculoskeletal symptoms when simulating handling tasks, regarding trunk movements and load support. Simultaneous lumbar movements and load support were quantified by a flexible electrogoniometer and load cell, respectively. Workers can adopt different motor strategies to perform similar tasks, possibly resulting in different physical demands. No previous studies on different movement patterns as a possible strategy for coping with physical demands by injured workers are available. 9 asymptomatic and 10 symptomatic industrial workers, carried a device for measuring contact between load and trunk during simulated tasks. An ANOVA was performed to compare results between symptomatic and asymptomatic workers. Most of the symptomatic workers supported the load on their trunk, whilst most of the asymptomatic workers did not. Higher values of lumbar flexion occurred for the symptomatic workers (P<0.05). Apparently, differences in movement and load support were adopted by injured workers as a possible strategy to share upper limb overload with other body regions. Workers suffering from work-related musculoskeletal disorders may adopt different motor strategies to cope with their job physical demands. An effort should be made to reallocate injured workers if major cost is to be avoided.