Many Lower Back Problems a Consequence of Body Shape -- Except Among Smokers
Dec. 28, 1999 (Atlanta) -- Personal characteristics are most often to blame
for lower back pain, rather than strenuous labor, concludes a new study from
the United Kingdom. However, another new study, this one from Canada, shows
that at least one physical act can cause lower back pain, especially in
adolescents: lifting a cigarette. Both studies appear in the December issue of
the journal Spine.
In the first study, researchers from the University of Bristol in the United
Kingdom and the Schulthess Clinic in Zurich, Switzerland studied 400 health
care workers. None of the volunteers suffered from serious back pain causing
them to miss work or seek medical attention. The volunteers completed
questionnaires and underwent a thorough physical examination and test. The
subjects' spines and hips were examined for curvature and mobility. Also, their
legs and backs were tested for strength. The volunteers then completed six
follow-up questionnaires over the next 3 years.
According to lead researcher Michael Adams, PhD, personal risk factors
accounted for only 12% of low back pain. "We found that certain physical
factors -- a long, stiff, and flat lumbar spine -- are better predictors of
first-time 'severe' low back pain than the psycho-social factors studied,"
Adams tells WebMD.
The study confirms previous research in many respects, but it also breaks
new ground. Adams tells WebMD that the study shows for the first time that a
stiff back (low range of bending movement, or low mobility) is an important
risk factor for low back pain. "Previous studies had given conflicting
results on this issue, probably because they used inaccurate 'clinical'
measures of lumbar mobility," says Adams. "We used an accurate
electromagnetic tracking device to measure lumbar mobility."
Adams says a second major finding is that physical risk factors have more
influence in those people who are starting out in a physically demanding new
job. "This had not been studied before," Adams tells WebMD. He believes
more research needs to be done to determine if people are more likely to
develop back pain when starting a new job based on their physical
characteristics, including trunk length, back muscle strength, and mobility.
Adams is a senior research fellow at Bristol University.
Adams says that behavior such as poor lifting technique naturally can cause
lower back pain. He also noted that one other behavior can: smoking.
Researchers whose findings appeared in the April 1999 issue of Occupational
Medicine came to the same conclusion.
D. Ehrmann Feldman, PhD, a post-doctoral fellow at the University of
Montreal who studied 500 students between grades 7 and 9, agrees. "The most
important finding of the study was that smoking appears to be a risk factor for
the development of low back pain in adolescents," Feldman tells WebMD.
"We found that teens who smoked were approximately 2.5 times as likely to
develop low back pain as nonsmokers. We also found a dose-response association;
those students who smoked more were more likely to develop low back