Life
Ever cracked your own neck, or helped to crack somebody else's? Perhaps you've been to a chiropractor or osteopath, and they've manipulated your head suddenly to one side or another to leave you with the swift "crack" noise and that sweet feeling of relief. Cracking your neck, or cervical manipulation, may be a standard part of the chiropractic arsenal, but it's a somewhat controversial practice that could, in rare cases, seriously mess up your arteries, and might even lead to stroke.
The sound caused by neck manipulation is thought to be part of the therapeutic benefit of the process, like cracking one's knuckles. The process itself, however may be placing people at risk. The problem? There are a number of arteries in your head and neck that are at risk of dissection with sudden manipulation.
But not everyone is sure of the link between neck-cracking and this rare injury. Chiropractors, scientists and doctors disagree amongst themselves about how bad the practice might be and whether neck-cracking is really a big risk factor, or if it's all hype. Throw in some contradictory studies, a lack of regulation and some under-reporting, and you have a pretty big mess. An impressive hooplah for something that looks, on the surface, like a simple way to cure a back-ache.
Why Don't We Know More?
Unfortunately, tracing strokes definitively back to neck cracking is extremely difficult, because vertebral artery bleeds can be caused by other things: neck injuries and accidents, genetic predispositions to artery weakness or hypermobility, or random incidents. "Some precipitating events associated with hyperextension or rotation of the neck," a 2008 study noted, "include practicing yoga, painting a ceiling, coughing, vomiting, sneezing, the receipt of anesthesia, and the act of resuscitation." Which means that pinning the blame on cracking one's neck at a chiropractor's or in an idle moment at a desk can be very tricky.
The fact that the professionals performing neck manipulations tend to be chiropractors or osteopaths is another factor that complicates matters. Chiropractors are sometimes regulated — the Professional Standards Authority in the UK regularly audits the General Chiropractic Council, for instance, while many American states require licenses — but in different areas of the world, it's less formal. That can create issues with collecting information about patients and their treatments, and with what training these practicitioners receive. When people aren't aware of the signs of vertebral dissection or the risks involved in neck cracking, it's also entirely possible that underreporting is also playing havoc with the numbers.
If you do want to crack your neck, experts do agree that the risks of stroke are incredibly low. But it might be worth being careful next time you feel the urge to do it yourself.