The relationship between chiropractic and stroke is controversial, with researchers offering evidence for both those claiming a link and those refuting the relationship. A limited number of strokes occurring during or immediately after chiropractic manipulation are reported to be statistically too small to be recorded, but can pose a risk to patients receiving neck adjustments. Some groups of medical professionals have issued press releases warning patients against receiving chiropractic adjustments to their necks because of the risk of stroke.
Spinal manipulation or adjustment is the most commonly used form of chiropractic technique; however, there are some links to stroke from neck manipulations. Chiropractic is a profession within the healthcare industry requiring extensive training and licensing to practice the techniques. Stroke is a medical condition caused by a change in the blood flowing to the brain resulting in the loss of brain cells and, in severe cases, death. Causes of a stroke include the bursting of blood vessels and the lack of blood passing to the brain.
A relationship between chiropractic and stroke is thought to be caused by the fast movement of the neck completed during a chiropractic manipulation to the vertebrae of a patient. Two arteries run through the vertebrae of the neck that can have the blood flow cut when the neck is forcibly manipulated, causing parts of the brain to be starved of blood and oxygen. The occurrence of stroke following chiropractic manipulations is of thought to occur between one and three times for every million adjustments that take place.
There is a failure of scientific research to provide a definite link between a stroke and the adjustment that took place around the time of the event. Chiropractic organizations argue that a stroke can occur at any time and a visit to a chiropractor around the time of the stroke does not guarantee a correlation between the two. Research also reports that chiropractic manipulations linked to stroke are often performed by people not trained and qualified to perform adjustments. Links between chiropractic and stroke are small enough to make the occurrence smaller than those of beauty parlor stroke syndrome, when a customer suffers a stroke from the motion of leaning back over a wash basin.
Insurance payouts for chiropractors in the U.S. in 2002 show that nine percent of all claims were made for stroke occurrences in chiropractic patients. Arguments are made that more strokes are caused by the manipulations completed by chiropractors than are reported because symptoms of the medical condition progress gradually over a number of days. Those representing chiropractor professionals report that the link between chiropractic and stroke is small when adjustments are performed by properly-trained professionals.
