Chiropractic treatment.
Vertebrobasilar stroke is a life-threatening brain injury that has sometimes been attributed to chiropractic treatment. This condition and its possible association with chiropractic treatment have been extensively studied.
Anatomy
The vertebral arteries are paired arteries that travel up through the neck, coursing through small holes in the sides of the neck vertebrae. These arteries come together to form the basilar artery. Branches from the basilar artery supply blood to the base of the brain. Together, these vessels make up the vertebrobasilar system. Interruption of circulation within this system can cause damage to the brain. This condition is called a vertebrobasilar stroke.
Causes of Vertebrobasilar Stroke
As the vertebral arteries course through the neck, they make sharp bends around the upper-most vertebra near the base of the skull. These sharp bends are located at a level where a considerable amount of rotation occurs in the neck. Most vertebrobasilar strokes are caused by tearing injuries at or near these vulnerable bends in the vessels. This trauma to the vessels leads to blood clotting. Clots can cause blockage of an artery at the injury site or they can break off and lodge further "down stream." Brain tissue that is no longer receiving a blood supply suffers the damage or cell death associated with a "stroke."
Chiropractic Association
Because certain chiropractic treatments or "adjustments" involve rapid rotation of the neck often associated with dramatic popping noises, it is not unreasonable to conclude that such movements might potentially injure the vertebral arteries. People diagnosed with vertebrobasilar strokes have often seen chiropractors just before they develop signs of a stroke. This adds further weight to the cause and effect assumption. Credible researchers have placed the associated risk of chiropractic manipulation and stroke at between 1 in 400,000 and 1 in 10 million, according to Allan Terrett in "Vertebrobasilar Stroke Following Manipulation."
Risk Perspective
Assuming that the majority of people who receive chiropractic neck adjustments consult chiropractors because of neck pain or other similar symptoms, Dabbs and Lauretti compared the risks of neck adjustments to the risks associated with non-steroidal anti-inflammatory medications (NSAIDs). NSAIDs are a class of drugs that includes aspirin, ibuprofen and naproxen. They are among the most commonly prescribed medications for neck pain. When comparing serious complications including death, these researchers concluded that cervical manipulation for neck pain is safer thanNSAIDs, by as much as a factor of several hundred times.
Best Evidence
The only large study to look for a true cause/effect connection between chiropractic treatment and vertebrobasilar stroke was performed in Canada. These researchers concluded that this type of stroke was very rare. The evidence suggests that people who are in the process of developing this type of stroke will often have associated neck pain or headaches. There was a lack of evidence to suggest that the chiropractic treatments were the cause of the strokes. In fact they found there was no increased occurrence of strokes suffered by those who consulted chiropractors compared with those who consulted medical physicians for the same symptoms.
Summary
Because of anatomical considerations, chiropractic adjustments should not be given to anyone suspected of early stroke symptoms. Research does not support a strong cause and effect link between chiropractic treatments and vertebrobasilar strokes in otherwise healthy people.
Tags: neck pain, associated with, cause effect, chiropractic treatments, vertebral arteries