Objectives
To investigate risk factors for low-back pain (LBP) presenting for magnetic resonance imaging (MRI), with special focus on whole-body vibration (WBV).
Methods
A case-control approach was used. The study population comprised working-aged subjects from a catchment area for radiology services. Cases were a consecutive series referred for a lumbar MRI because of LBP. Controls were age- sex-matched subjects X-rayed for other reasons. Subjects were questioned about physical factors loading the spine, psychosocial factors, driving, personal characteristics, mental health, and certain beliefs about LBP. Exposure to WBV was assessed by six measures, including weekly duration of professional driving, hours driven at a spell, and current r.m.s. A(8). Associations with WBV were examined with adjustment for age, sex, and other potential confounders.
Results
Altogether, 252 cases and 820 controls were studied, including 185 professional drivers. Strong associations were found with poor mental health and belief in work as a causal factor for LBP, and with occupational sitting for ≥3 hours while not driving. Associations were also seen with taller stature, consulting propensity, BMI, smoking history, fear-avoidance beliefs, frequent twisting, low decision latitude and low support at work. However, associations with the six metrics of WBV were weak and not statistically significant, and no exposure-response relationships were found.
Conclusions
We found little evidence of a risk from professional driving or WBV. Drivers were substantially less heavily exposed to WBV than in some earlier surveys. Nonetheless, it seems that at the population level, WBV is not an important cause of LBP referred for MRI.