Is it possible to suffer a stroke from cracking your neck? The short answer is yes, but it is an extremely rare occurrence primarily associated with forceful, sudden movements, such as aggressive self-manipulation or a high-velocity professional adjustment. This risk is tied to a specific type of injury to the blood vessels that supply the brain. Understanding this mechanism requires knowing the anatomy of the neck and the precise nature of the injury.
The Arterial System in the Neck
The brain receives its blood supply from four major vessels that travel through the neck: the two carotid arteries and the two vertebral arteries. The internal carotid arteries run along the front sides of the neck, delivering blood primarily to the front portion of the brain. They ascend into the skull through the temporal bone.
The vertebral arteries are particularly relevant to neck rotation injury. These vessels travel upward through small bony openings, called transverse foramina, in the cervical vertebrae. They wind around the first vertebra, the atlas, before joining inside the skull to form the basilar artery, supplying the brainstem and the back of the brain.
Because the vertebral arteries pass directly through the bony tunnels of the spine, they are vulnerable to stretching or compression during extreme or sudden neck movements. The internal carotid arteries are also susceptible to injury from hyperextension or rotation. Any undue force on these vessels can disrupt the delicate lining of the artery wall.
How Neck Movements Cause Injury
The specific pathology that connects neck movement to stroke is known as Cervical Artery Dissection (CAD). This condition occurs when a small tear forms in the innermost layer of the artery wall, known as the intima. This tear allows blood to leak into the space between the layers of the artery wall.
This pooling of blood within the wall forms a hematoma, which can either narrow the vessel or completely block it, impeding blood flow to the brain. In some cases, the injury causes a clot to form on the roughened inner surface of the artery. If this clot, or a piece of it, breaks off and travels upstream to the brain, it is called an embolism.
An embolism that blocks a smaller blood vessel in the brain causes an ischemic stroke, starving brain cells of oxygen. This mechanism explains why neck manipulation is considered a potential trigger for stroke. Dissection of a cervical artery is one of the most common causes of stroke in younger adults.
Evaluating the Actual Stroke Risk
The risk of stroke following neck cracking or manipulation is statistically very low. The discussion often separates the risk of self-cracking versus professional high-velocity, low-amplitude adjustments. While self-cracking is considered lower risk, it can still be a trigger if it involves extreme force or range of motion.
Professional cervical manipulation carries a small, well-documented association with cervical artery dissection, particularly of the vertebral arteries. Estimates suggest the risk of a severe event following manipulation is in the range of 1 in 20,000 manipulations. This risk is comparable to the risk associated with common daily activities like turning your head to check a blind spot while driving.
The medical community also debates whether the manipulation actually causes the dissection or if the patient was already experiencing the injury when they sought treatment. Dissection often causes neck pain and headache as early symptoms, which are the same reasons patients seek manipulation. This “protopathic bias” suggests that the manipulation may merely coincide with, or hasten the progression of, an injury that was already underway. Patients with pre-existing risk factors, such as connective tissue disorders or recent minor trauma, may be more vulnerable to the effects of forceful neck movement.
Recognizing Signs of Arterial Damage
The initial sign of cervical artery dissection is often a severe, unusual headache or neck pain that starts abruptly. This pain may be localized to the back of the neck or the head, often on one side. Other neurological symptoms that indicate blood flow disruption to the brain may follow the pain.
These can include a sudden onset of dizziness or vertigo, double vision, or unsteadiness when walking. More traditional stroke signs, such as slurred speech, facial drooping, or weakness in an arm or leg, are also serious indicators.
Any person who experiences these symptoms immediately or shortly after cracking their neck should seek emergency medical evaluation. Treatment to prevent clot formation and minimize brain damage is most effective when administered in the hours immediately following a stroke event.