Chiropractic Neck Treatments Increase Risk of Stroke
In fact, she tells WebMD, it's not possible to know if the chiropractic manipulation actually caused the VBA. "We can only infer based on the timing of events," she says.
"This is not a public health problem," says William J. Powers, MD, professor of neurology at Washington University School of Medicine in St. Louis.
"There's always the possibility that something else -- some other trauma to the neck -- could have caused the pain and the [injured artery] -- and that's what sent them to the chiropractor," Powers tells WebMD. Whiplash from a car accident can cause similar trauma to arteries, for instance.
"In many cases, there is no history of trauma at all," he says. "In others, something mild may have happened, but the blood vessel was already weakened."
What Rothwell and colleagues actually found, says Powers, "is over a period of six years -- in all of Ontario -- six patients under age 45 who had chiropractic manipulation within one week of stroke. So this is very, very rare; it causes very few strokes. If you get your neck manipulated, your chances are very, very low of getting it ... but still, about five times higher than if you didn't."
Powers says that for years he has advised against chiropractic manipulation.
"When people ask me, I specifically say that it's OK to get your lower back manipulated, but don't let them mess with your neck," she tells WebMD.
"The type of data Rothwell used is not the most reliable, says Larry Goldstein, MD, director of the Stroke Center at Duke University in Durham, N.C.
"It can only show that visits to the chiropractor and this type of stroke are associated, not that the one causes the other," he tells WebMD. "We've all seen patients who have had neck manipulations and minor neck trauma or no neck trauma that have developed ... stroke. They're reporting that there seems to be a relationship between recent manipulation and stroke. Even with that though, the overall risk appears to be somewhat low -- 1.3 cases per 100,000 under age 45 receiving chiropractic manipulation -- that's pretty low."