Back pain has reached epidemic
proportions. The figures are sobering - there is a 70 percent chance that you
will suffer from it at some point in your life and a 30 percent chance that you
have had a back pain attack in the last 30 days. At any point of time about 1
percent of working age Americans are incapacitated by their lower lumbar
regions and treatment is pretty much expensive accounting for $26 billion per
year which is about 3 percent of the total health care spending.
There has been a marked difference in
the way we treat back pain with the discovery of MRI in the 1980s. Previous to
that doctors had very little information or idea about the lower back region
which is an exquisitely complicated body area full of tiny bones, ligaments,
spinal discs and minor muscles. In the absence of information the only recourse
that a doctor could take was to advice bed rest and surprisingly this proved to
be a very effective remedy in that 90 percent of the patients got better within
seven weeks. With the discovery of MRI in the 1980s doctors have a
stunningly accurate image of the lower back region but ironically that has made
the problem worse. The machine simply gives too much of information and doctors
as a result are unable to distinguish the significant from the irrelevant. The
stunningly accurate images of the lower lumbar regions seen through an MRI are
often misleading. The disc abnormalities which are apparent are seldom the
cause of chronic back pain. In a 1994 an interesting study published in the New England Journal of Medicine,
obtained images of the spinal regions of 98 people who had no history of back
pain whatsoever. The images were then sent to doctors who didn't know that the
patients weren't in pain. The result was shocking. The doctors reported that
two-thirds of these normal patients exhibited "serious problems" such
as bulging, protruding, or herniated discs. In 38 percent of these patients,
the MRI revealed multiple damaged discs and nearly 90 percent of the patients exhibited
some form of disc degeneration. These structural abnormalities are often used
to justify surgery which sounds quixotic for people who have no history of back
pain.
Similarly a large study published in
the Journal of American Medical
Association (JAMA) randomly assigned 380 patients with back pain to undergo
two different types of diagnostic analysis. One group received x rays while the
other group got diagnosed using MRIs which provided the doctors with much more
detailed information about the underlying anatomy. Which group fared better?
There was no difference in patient outcome. The vast majority of people in both
groups got better - thus clearly more information didn't lead to less pain. But
stark diff fences emerged when studies looked at how different groups were
treated. Nearly 50 percent of the MRI patients were diagnosed with severe disc
abnormalities requiring intensive medical interventions. These treatments were
obviously more expensive and they had no measurable benefit.
Thus there is a danger of too much
information and it can seriously interfere with our understanding. When the prefrontal cortex is overwhelmed,
a person can no longer make sense of the situation. Correlation is confused
with causation and people end up making theories out of coincidences. MRIs make
it easier for doctors to see the lower lumbar region in vivid details
highlighting all sorts of disc problems and so they reasonably conclude that
these structural abnormalities are the cause behind back pain. They are usually
wrong. Medical experts are now encouraging doctors not to order MRIs when
evaluating back pain. A recent report in the New England Journal of Medicine, that MRIs should be used to image the back only under specific clinical circumstances - such as patients with a strong clinical suggestion of underlying infection, cancer or persistent neurologic deficit. In the latest clinical guidelines issued by the American College of Physicians and the American Pain Society, doctors were strongly recommended ... not to obtain imaging or other diagnostic tests in patients with non-specific low back pain. In too many cases expensive tests proved worse than useless and all the vivid imagery and detailing got in the way of effective diagnosis. Doctors thus performed better with less information.
This interesting write up with some amount of editing on my part has been taken from the chapter titled "Choking on Thought" from, How We Decide by Jonah Lehrer,
Mariner Books, Houghton Mifflin Harcourt, Boston, New York, 2010.
