Back disorders and nonneutral trunk postures of automobile assembly workers.
Punnett L; Fine LJ; Keyserling WM; Herrin GD; Chaffin DB
Scand J Work Environ Health 1991 Oct; 17(5):337-346
The goal of this study was to investigate the potential relationship between the use of nonneutral trunk postures at work and the risk of musculoskeletal back disorders reported to an industrial medical department. The specific postural and biomechanical demands of jobs performed in an automobile assembly facility were evaluated and compared for workers with and without back disorders. Ninety five workers with back pain (cases) and 124 referents free of back pain were included in the study. Many of the study jobs involved substantial postural loading of the trunk muscles. Of the 219 study participants, there were 185 subjects who worked with the trunk in mild flexion for any amount of time during the workday, 112 subjects who were exposed to severe trunk flexion for any length of time, and 98 subjects who were exposed to work with the trunk bent laterally or twisted. Only 20 workers could be classified as unexposed on the basis of maintaining the trunk in a neutral posture during the entire job cycle. The cases were approximately five time more likely than the referents to work with the trunk in mild flexion and about six times more likely to work with the trunk either in severe flexion or twisted or bent sideways. The risks of injury increased with exposure to multiple postures and increasing duration of exposure.
NIOSH-Author; Back-injuries; Musculoskeletal-system-disorders; Epidemiology; Risk-analysis; Risk-factors; Workplace-studies; Repetitive-work;
Author Keywords: back pain; ergonomics; job analysis method s; musculoskeletal disorders; postural analysis; repetitive work; video recording
Dr L Punnett, Department of Work Environment, University of Lowell, One University Avenue, Lowell, MA 01854, USA
Scandinavian Journal of Work, Environment & Health