Research is showing that the pain often has nothing to do with the mechanics of the spine, but with the way the nervous system is behaving, according to Dr. James Rainville of New England Baptist Hospital in Boston.
"It's a change in the way the sensory system is processing information," says Rainville, who is a physiatrist, or specialist in rehabilitation medicine.
says that about 25 percent of patients with acute back trouble get stuck in an endless loop of pain.
thinks this chronic back pain is often due to persistent hypersensitivity of the nervous system.
Genetics may help explain why back pain becomes chronic for that 25 percent.
But whatever the underlying cause, Rainville
and others have discovered that many of them can learn to ignore their pain.
explains: "In primitive cultures, if you lived near a volcano and the volcano started smoking and looking like something was going to happen, well, it was obvious[ly] because gods were mad at you.
And you'd start doing silly things - sacrificing chickens or goats or whatever, thinking that that would appease the gods."
In a strange way, Rainville
says, people with chronic back pain do something very similar.
They sacrifice parts of their life - playing golf or softball, running, picking up bags of groceries or grandchildren.
Patients get so afraid of pain, they do anything to avoid it.
"They keep putting things onto this altar, thinking that's going to change the situation," Rainville