proposed causes of low back pain include the idea that certain
immune cells are responsible for chronic back pain. In a paper by
Freemont et al. Mast cells are postulated to be good candidates for
further study into new therapies.
Mast cells in the pathogenesis of chronic back pain: a
Freemont AJ, Jeziorska M, Hoyland JA, Rooney P, Kumar S.
J Pathol 2002 Jul;197(3):281-5
Chronic Pain Linked
to Atrophic Gray Matter Changes
By Merritt McKinney NEW YORK (Reuters Health) Mar 21 -
People with chronic back pain may experience atrophic changes in
the gray matter of the brain, according to study findings presented
Thursday at the annual meeting of the American Pain Society in
Chicago. Still, the temporal nature of the relationship is unclear.
But if chronic pain turns out to be a cause of gray matter atrophy,
"the urgency to cure chronic pain becomes more important,"
according to Dr. A. Vania Apkarian at Northwestern University in
Chicago, Illinois, principal investigator in the ongoing study. In
previous research, Dr. Apkarian and his colleagues found that people
with chronic pain may experience gray matter changes. In the new
study, Dr. Apkarian's team continued to examine the brains of
patients with chronic pain, in this case 10 people with chronic back
pain. The gray matter of these patients was compared with that of 20
people without chronic pain. Compared with control subjects, chronic
pain patients had less overall and thalamic gray matter. Not only
was there less gray matter in terms of volume, but the tissue was
also less dense, Dr. Apkarian said. "We have shown that brain
chemistry is abnormal in chronic back pain patients," Dr.
Apkarian said. He cautioned however, that "we have no idea"
whether the shrinkage causes the back pain or is a result of it. In
a future study, Dr. Apkarian said he would like to follow a group of
people with chronic pain to see if the changes in gray matter
progress. If gray matter continues to shrink as the pain continues,
it would support the idea that the atrophy is caused by chronic
pain, he said. One question Dr. Apkarian would like to see answered
is whether treating the pain can reverse the damage to the brain's
gray matter, although he said such a reversal is unlikely.