Patients receiving treatments from a chiropractor or osteopathic doctor face a heightened risk of suffering a stroke, according to a Loyola University-led study.
The researchers said that energetic thrusts and rotations, sometimes used in neck massage therapies, may lead to a condition called cervical artery dissection - causing a small tear in the artery walls in the neck. A tear in the artery wall can trigger a stroke if a blood clot forms at the site and later dissolves to block a blood vessel in the brain.
Such a tear "occurs with a sudden movement that can hyperextend or rotate the neck, such as one you may see with whiplash or sporting events, or even violent coughing or vomiting," said author Dr. Jose Biller, chair of neurology at the Loyola University Chicago Stritch School of Medicine. "The techniques for cervical manipulation, even though they vary among health professionals, include a rotation of the neck and sometimes a forceful thrust," webmd reports.
The researchers said that these artery wall injuries are an important cause of stroke in young and middle-aged adults. Nearly 8 percent to 25 percent of stroke cases in patients, younger than 45 years, have been reported.
Although previous studies have showed an association between neck manipulation and stroke in patients aged 45 years and younger, there has not been enough evidence to prove that the practice is the reason for the strokes. The researchers, however, suggest chiropractors and osteopathic physicians to warn patients of this link.
"Two studies that have come out recently said that there is no evidence that the force or direction utilized in cervical manipulation reaches the threshold of stretching the arteries to the point that they can be damaged. Professionals who perform neck adjustments apply force that is no greater than what people can do in activities of daily life," said Keith Overland, former president of the American Chiropractic Association and a doctor of chiropractic in Norwalk, Conn.
The finding is published in the journal Stroke.
