Despite many people having chiropractic treatment without incident, the consequences of some neck manipulations can be devastating, because of the severity of the resulting injuries.
The New York Times reports that while many critics claim the field lacks scientific validity, it’s acknowledged that the treatments can provide pain relief, but given the delicate nature of the spine, particularly the upper vertebrae of the neck, complications, which are generally uncommon, could be life-altering.
One injury in particular, arterial dissection, in which blood vessels that supply blood from the heart to the brain are torn, is highly concerning. In some cases, a patient may be unaware an injury has occurred, and the damage will heal on its own. In others, a tear in the artery wall can cause a clot to form and result in a stroke, even death.
It is unclear how common the complication is after chiropractic care. One estimate says an arterial dissection occurs in one out of 1 000 neck manipulations, another says one in 5.8m (three of the four authors on that study worked for chiropractic associations).
Because of the severity of the injury, though, many spine specialists warn that chiropractic manipulation of the neck can be dangerous.
The risks
Chiropractic manipulations involve high velocity, low amplitude movements of the spine. “We take the joint to its limited range, and do a very quick push on that joint – that’s the high velocity aspect,” said William Lauretti, a professor of integrated chiropractic therapies at Northeast College of Health Sciences and a spokesman for the American Chiropractic Association. “But we’re moving it for a very, very small range – that’s the low amplitude.”
The concern over arterial tears is specific to neck manipulations. That’s partly because the neck is more mobile and thus more susceptible to injury; the torso is protected by the ribs, so the lower back doesn’t rotate as much. Major arteries that distribute blood from the heart to the brain are also threaded through the neck vertebrae, making the blood vessels there more vulnerable.
“When you turn the neck side to side, those vessels will rotate within the bone,” said Dr Betsy Grunch, a neurosurgeon in Gainesville. “If you turn your head quickly or rotate quickly, like a car accident or manual manipulation or sport, the vessel can get abruptly torqued.”
The most common symptoms of an arterial dissection are headaches, dizziness and vertigo; weakness, numbness or paralysis on one side can also occur.
In a case last year, a student (28) at Georgia Southern University named Caitlin Jensen became dizzy and nauseated after a chiropractor manipulated her neck. The chiropractor called 911 and at the hospital, doctors determined she had tears in four blood vessels, resulting in a stroke and cardiac arrest.
Nine months later, Jensen has just started to be able to speak again, though she still cannot walk or swallow. The right side of her body was paralysed by the injury, as were her vocal cords. Her mother told The New York Times her daughter was making progress in her recovery, but that it was slow going.
It’s virtually impossible to know how common cases like Jensen’s are, because “there is no monitoring system to record such events”, said Edzard Ernst, an emeritus professor of complementary medicine at the University of Exeter in Britain. “Many patients sue the chiro and settle out of court. Many patients have a stroke and might never connect it to the manipulation.”
One study of more than 50 000 cervical spine manipulations found that about 16 in 1 000 resulted in fainting, dizziness and light-headedness. Other researchers have tried to assess the risk by working backward: finding people who experienced an arterial dissection and determining whether a significant proportion recently had their necks manipulated by chiropractors.
For example, a small study found that 15% of arterial dissections occurred after a sporting activity, and 11% followed a chiropractic manipulation.
Several studies have shown the risk of arterial dissection and stroke to be three to 12 times higher in people who’ve recently had a neck manipulation, according to a review by the American Heart Association’s Stroke Council.
Grunch, who treats one or two patients with the injury every year, said the connection is clear: “Arterial dissection is a known complication of spinal manipulation.” So even though the risk is rare, she strongly advises against having it.
Dr Alan Hilibrand, the chief of spine surgery at the Rothman Orthopaedic Institute in Philadelphia and a former president of the Cervical Spine Research Society, said that “there’s no smoking gun” in the scientific literature tying chiropractors to arterial dissections. But, he added, “I’m very uncomfortable” with it.
Are chiropractors being unfairly blamed?
Many chiropractors dispute the claim that their treatments can cause such significant harm. They point to review papers that have found no link between neck manipulations and arterial tears, and research showing that people who visited a primary care doctor were just as likely to have a stroke in the weeks after the appointment as people who saw a chiropractor.
Instead, they say, a visit to a chiropractor is more often the result of an arterial dissection, not the cause of it.
“These patients have an artery that’s been injured in some way, causing neck pain and headaches,” Lauretti said. “Some go to their primary care doctor; some go to their chiropractor. If the patient has a stroke after a visit to the chiropractor, the chiropractor gets blamed.”
When a patient goes to a chiropractor for neck pain, Lauretti added, the practitioner must do a thorough examination to rule out any “red flags” before performing a neck manipulation.
Acknowledging the vulnerability of the neck, some chiropractors take a more conservative approach when treating the area.
Philip Cordova, a chiropractor in Houston, said that in his office, they don’t rotate the neck very far in an effort to minimise the chance of injury. Some patients also tell him, “‘I don’t want my neck adjusted,’ and that’s not a problem,” Cordova said. “We work around that.”
The risk of complications from chiropractic treatment of other parts of the spine is extremely low, and some research suggests that the practice is as beneficial as home exercise, physical therapy and medication. As a result, many orthopaedic surgeons and neurosurgeons – including Grunch and Hilibrand – will occasionally refer patients to chiropractors for issues unrelated to the neck.
“I think incorporating chiropractic treatment as a part of a conservative treatment plan is totally appropriate,” Grunch said.
So what to do about neck pain?
Accidents stemming from chiropractic manipulations are very uncommon, but because of their potential severity, there are several other options available for neck pain.
Hilibrand recommends over-the-counter pain medications combined with physical therapy. “Eighty percent of people with neck pain will get better after the first six weeks with just those two interventions,” he said.
Hillbrand also recommended alternative therapies, like acupuncture or a massage technique known as myofascial release.
In instances of spinal compression, though, he said people should avoid chiropractors altogether.
See more from MedicalBrief archives:
Chiropractic neck manipulation and vision loss
In defence of chiropractic: DUT, Casa and Prof Noakes
The ‘sheen of respectability’ that surrounds chiropractic