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You probably don't give much thought to your neck, unless something goes wrong and you start to feel neck pain. This underappreciated body part has to be strong enough to support a heavy weight (your head) yet still allow you to tilt, turn, and nod your head easily.

Most of the time, neck pain doesn't signal a serious medical problem. But it's worth learning about one of the rare exceptions: a tear in one of the arteries of the neck, known as a cervical artery dissection (see "What is a cervical artery dissection?"). Although these occur in only about two in 100,000 people per year, they are one of the most common causes of stroke in people under age 50.

Over the past two decades, awareness of cervical artery dissection has grown. This may stem in part from the recognition that stroke rates seem to be rising among younger people, despite an overall downward trend in deaths caused by stroke.

More common before age 50

Cervical artery dissections are seen more often in younger adults for two main reasons. First, a small percentage of people have underlying inherited connective tissue disorders that make their arteries more likely to tear. For these people, an artery tear is more likely to manifest at a younger age. In older people, other types of strokes (such as those associated with brain arteries narrowed by fatty plaque) are more common. But dissections can still happen in older people. A study in the journal Neurology found that one in 14 people diagnosed with a cervical artery dissection was age 60 or older.

The second (and perhaps bigger reason) artery dissections are more common before age 50? Younger adults are more likely to engage in exercise that involves neck movements that can precipitate a tear. Dissections have also been reported after strenuous weightlifting, head-flinging dance moves, and even yoga. If not done properly, certain positions such as a shoulder stand can cause hyperextension of the neck.

Hairdresser and chiropractor cautions

You can also hyperextend your neck while tipping your head back to have your hair washed at a salon sink. Even though there are only a dozen or so such cases described in the medical literature, there's a name for this phenomenon: "beauty parlor stroke syndrome." To play it safe: Ask your hairdresser for a neck extension, which is a little cushion that props up your head so you don't feel any strain on your neck.

Not surprisingly, whiplash sustained during a car accident can also cause a cervical artery dissection. And in rare cases, so can the quick, thrusting neck movements some chiropractors and other health care professionals use to treat neck pain, known as cervical manipulative therapy or "adjustment." However, it's not clear whether the neck therapy itself causes the tear, or whether the pain from an existing tear might prompt people to seek out such treatment.

Unusual, persistent neck pain

With a cervical artery dissection, the neck pain is unusual, persistent, and often accompanied by a severe headache. The neck pain from a carotid artery tear often spreads along the side of the neck and up toward the outer corner of the eye. A vertebral artery tear may feel like something sharp is stuck in the base of your skull. If you experience such pain — especially if you also have stroke symptoms such as dizziness, double vision, jerky eye movements, unsteadiness while walking, or slurred speech — call 911 immediately.

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