The chiropractor had just worked on Lynne Beliveau's neck when she became dizzy, unable to see or move. Rushed to the hospital, Beliveau had a shunt inserted to relieve pressure caused by swelling in her brain. The Ashburn, Va., woman suffered a series of strokes and today, eight years later, the 41-year-old mother of three suffers from constant vertigo.
Elizabeth Haran Caplan knew she was in trouble seconds after a chiropractor in Oklahoma City manipulated her neck. The room got dark and she felt dizzy. Because of her years of service as a combat medic in Kosovo and Somalia, she knew what was happening and yelled, "Stop. I'm having a stroke." More than a decade later, she is blind in her left eye and has problems swallowing without choking due to paralysis of one side of her throat.
Approximately 20 million Americans visit chiropractors each year, according to the American Chiropractic Association, seeking relief from back pain, neck pain, headaches, sinus problems, ringing in the ears and more. For many, the manipulations provide relief. But one of the techniques chiropractors use, called cervical neck manipulation, or "cracking the neck," has raised concerns that it can cause serious harm.
"I have jumped out of airplanes, escaped bullets in Somalia," said Haran Caplan, 47, who retired from the Army nine years ago as a lieutenant colonel. "Who knew the most dangerous place I would put myself would be on a chiropractor's table?"
David Walls-Kaufman, a Washington chiropractor who has practiced for more than 30 years, said every patient comes with "two neurological snags," or problem areas: the neck and the spine.
"It's important to work on the neck if we are going to cure their problems," he said.
Walls-Kaufman sits on the guidelines committee of the national Council on Chiropractic Practice, which describes its mission as providing evidence-based guidelines that "serve the needs of the consumer and are consistent with 'real world' chiropractic practice."
Evidence of the effectiveness of chiropractic manipulation is inconclusive, in part due to a lack of large, rigorously designed studies. Some studies suggest that spinal manipulation may be helpful for lowering blood pressure, dealing with some headaches, helping colicky infants, limiting migraines and easing some types of lower back pain.
Others, however, have raised concerns specifically about the sudden powerful thrusts used in cervical neck manipulations and the possibility that they might tear the carotid or vertebral artery leading to the brain. Such tears can cause a blood clot that travels to the brain, causing a stroke.
A 2010 study of deaths after spinal manipulation found 26 published cases, and seven unpublished ones, mostly due to a tear, or "dissection of a vertebral artery," and suggested that many more cases had not been reported.
A 2007 survey of adverse effects published in medical journals between 2001 and 2006 found that "spinal manipulation, particularly when performed on the upper spine, is frequently associated with mild to moderate adverse effects. It can also result in serious complications such as vertebral artery dissection followed by stroke."
It noted that "survey data indicated that even serious adverse effects are rarely reported in the medical literature." A 2013 survey of 43 studies conducted between 2001 and 2011 found 707 incidents of stroke associated with cervical spinal manipulation therapy, but the authors said that understanding such incidents was hampered by inadequate reporting.
The American Chiropractic Association says that "neck manipulation is a remarkably safe procedure. While some reports have associated upper high-velocity neck manipulation with a certain kind of stroke, or vertebral artery dissection, recent evidence suggests that this type of arterial injury often takes place spontaneously, or following everyday activities such as turning the head while driving, swimming, or having a shampoo in a hair salon."
Stephen Perle, a spokesman for the American Chiropractic Association, said, "There is no such thing as 'chiropractic stroke,' any more than there is 'unhappiness heartburn.' There are strokes and VAD (vertebral artery dissection) that produce strokes. The name alone (i.e., 'chiropractic stroke') defines causation when that is not known," since many people go to chiropractors when they have neck pain that may be have turned into a stroke without manipulation.
Perle said that strokes after a cervical manipulation are "exceedingly rare" and that further studies are needed to prove any connection.
Perle and other chiropractors cite a 2008 Canadian study that found that of those who had strokes following neck manipulation, most had already been having symptoms suggestive of a stroke.
Felipe Albuquerque, a neurosurgeon in Phoenix who has studied stroke injury after neck manipulation, said that assertions that those who suffer tears in their neck arteries would have had a stroke regardless of the treatment suggest an "uncanny coincidence." He believes the patients that he has seen who had strokes following chiropractic manipulation had either a new arterial injury or one made worse by the manipulation.
"The epidemiology of these injuries is almost impossible to ascertain," Albuquerque and others wrote in a 2011 study in the journal Neurosurgery. "Studies suggest their incidence to be between 1 in 100,000 and 1 in 6,000,000 manipulations. Given that Americans visit chiropractors more than 250,000,000 times per year and that 30 percent of these visits involve cervical manipulation, the incidence of arterial dissection is likely to be higher than the lowest estimates. A significant number of dissections may go unreported either because they are mild or asymptomatic."
Walls-Kaufman says the possibility of stroke caused by neck manipulation doesn't cross his mind when patients come to see him because it is so rare. "I've never heard of one (happening)," he said. He employs what he says is a safer method of neck manipulation, one that involves twisting the head toward the shoulder in a way that does not challenge the artery. Alan Lichter, another Washington chiropractor, says he also uses a "more gentle" neck manipulation.
Although Lichter says that "more and more research shows that those who have strokes had a pre-existing condition. … There may be some risk for people who are already at risk."
Haran Caplan said she wishes she had been told beforehand that there was a risk, even very slight, in neck manipulation. She had gotten treatment many times before and doesn't recall ever being given a consent form. Given her medical background, she says she never would have gone ahead with the treatment if she'd read that there was an even rare risk of a stroke. "I would have read it and left," she said.
Beliveau, who had gone to the chiropractor due to lingering back pain from a car accident, said she also would not have done the treatment if she had known.
Keith Overland, president of the American Chiropractic Association, said through spokeswoman Melissa Lee that the group "supports informed consent and shared decision-making with patients. … It is up to doctors to determine what they communicate to their patients based on a thorough health history and examination, as well as consideration of local laws and legal standards."
The parents of Jeremy Youngblood wish their son had understood the risk. A healthy 30-year-old, Youngblood went to a chiropractor in Oklahoma City in 2011 for neck manipulation, seeking relief from lower back pain. It was his first visit. He died four days later. An autopsy report said he died of "acute cerebellar infarction due to manipulation of neck."
Wade Smith, a neurologist and one of the authors of a 2003 study that found chiropractic manipulation to be an independent risk factor for stroke, said chiropractors need to warn people, even if the risk is small.
"If the practitioner does not want to discuss risks, then you shouldn't go to that person," Smith said.