American Journal of Public Health, Vol 91, Issue 7 1069-1075, Copyright © 2001 by American Public Health Association
Biomechanical and psychosocial risk factors for low back pain at work
MS Kerr, JW Frank, HS Shannon, RW Norman, RP Wells, WP Neumann and C Bombardier
Institute for Work and Health, Department of Public Health Sciences, University of Toronto, Ontario, M4W 1E6, Canada. mkerr@iwh.on.ca
OBJECTIVES: This study determined whether the physical and psychosocial
demands of work are associated with low back pain. METHODS: A case-control
approach was used. Case subjects (n = 137) reported a new episode of low
back pain to their employer, a large automobile manufacturing complex.
Control subjects were randomly selected from the study base as cases
accrued (n = 179) or were matched to cases by exact job (n = 65).
Individual, clinical, and psychosocial variables were assessed by
interview. Physical demands were assessed with direct workplace
measurements of subjects at their usual jobs. The analysis used multiple
logistic regression adjusted for individual characteristics. RESULTS:
Self-reported risk factors included a physically demanding job, a poor
workplace social environment, inconsistency between job and education
level, better job satisfaction, and better coworker support. Low job
control showed a borderline association. Physical-measure risk factors
included peak lumbar shear force, peak load handled, and cumulative lumbar
disc compression. Low body mass index and prior low back pain compensation
claims were the only significant individual characteristics. CONCLUSIONS:
This study identified specific physical and psychosocial demands of work as
independent risk factors for low back pain.