Medical researchers are trying a new treatment for low back pain. Their hope is that harvesting and then re-injecting the body's own bone marrow -- which is rich in stem cells -- may repair worn-out discs in the spine.
In a small new study, the approach appeared to be safe -- and none of the patients reported that their pain got worse after the procedure.
But both the doctors who are testing the technique and outside experts say much more research is needed before they can say whether the treatment offers real relief.
"I tell everybody that this is experimental, with a capital E," said Dr. Joseph Meyer Jr., an anesthesiologist and pain medicine specialist at the Columbia Interventional Pain Center, in St. Louis. "We don't know if it works. I do believe that it's safe, but it might not do anything for you."
For the study, Meyer and his colleagues reviewed the case histories of 24 patients who were injected with their own bone marrow aspirate cellular concentrate (BMAC). Bone marrow concentrate contains adult stem cells, which have been called the body's own repair kit because they can change into -- and potentially heal -- different kinds of tissues.
Meyer's patients reported suffering from chronic low back pain for anywhere from three months to 12 years. Imaging tests showed that all the patients had some evidence of degeneration, or damage, to the discs that cushion the bones of the spine. Disc degeneration is common with age, and it is thought to be a major cause of low back pain.
Many times, exercise and weight loss can help people with persistent low back pain. But if conservative approaches fail and the pain becomes debilitating, Meyer said, the next option is invasive spinal fusion surgery.
"Fusion is a big, big step with questionable effectiveness," he said. "Often, you're back in the same boat a year later."
Meyer said he offered patients the bone marrow treatment as something to try before resorting to surgery.
For the procedure, he used a long needle to extract bone marrow from the back of the hip. The bone marrow was spun in a centrifuge to concentrate the cells and then injected into the space around a damaged disc. Meyer said the treatment costs a few thousand dollars and is not covered by insurance.
Of the 24 patients who initially received the bone marrow injections, half went on to have other procedures over the next 30 months, making it impossible to know what might have affected their back pain.
Of the 12 who had no other kinds of treatment, 10 reported that their pain lessened in the two to four months after their injections. After a year, eight patients were still reporting significant pain relief, while three said their back pain had not improved. One patient had not yet reached the 12-month mark. After two years, five said their back pain was better, and three had no improvement. For the other four, it was still too early to tell.
Meyer said none of the 24 patients who tried the technique had complications from their procedures, but injections always carry the risk of infection.
The study was scheduled for Thursday presentation at the annual meeting of the American Academy of Pain Medicine in Fort Lauderdale, Fla. Studies presented at scientific conferences usually haven't been scrutinized by independent experts, and their results are considered preliminary.
An expert who was not involved in the study said people with back pain shouldn't get too excited about these results, particularly since there was no control group used for comparison.
"Low back pain often gets better over time," said Dr. Richard Deyo, a professor of evidence-based medicine and a back pain expert at Oregon Health and Sciences University, in Portland. "Even patients who have chronic pain, their symptoms tend to wax and wane and fluctuate. They seek care when their symptoms are worst, and very often they drift back to their average level of pain, which looks like improvement."
"People grasp at straws, and they shouldn't. We have a long history of treatments that look promising when they start and turn out to be no more effective than placebo interventions," said Deyo, who also is deputy editor of the journal Spine. "We also have a history of treatments that, in some cases, turned out to be harmful. It's really too early to know if this is going to be effective or safe."
The study's authors agreed. They said they hope this pilot project will encourage more research.
"We hope it will get people thinking and hopefully promote a future controlled study," Meyer said.