Jaw Dysfunction May Intensify Migraines

A new study reveals an association between migraine attacks and temporomandibular joint dysfunction (TMJ). TMJ is a stress-related condition and is characterized by joint pain, reduced jaw movement, clicking or popping of the temporomandibular joint, and neck and face pain.

Researchers at the University of São Paulo’s Ribeirão Preto School of Medicine (FMRP-USP), in Brazil, discovered that the more frequent the migraine attacks, the more severe the TMJ. The temporomandibular joint acts like a sliding hinge connecting the jawbone to the skull, therefore the disorder’s symptoms includes difficulty chewing and joint tension.

“Our study shows that patients with chronic migraine, meaning attacks occurring on more than 15 days per month, are three times as likely to report more severe symptoms of TMJ than patients with episodic migraine,” said Lidiane Florencio, the first author of a study of women with migraines.

Previous studies have indicated that a migraine is somehow associated with pain in the chewing muscles. However, this research was the first to consider the frequency of migraine attacks when analyzing its connection with TMJ.

In the study, eighty-four women in their early to mid-thirties were assessed; 21 were chronic migraine patients, 32 had episodic migraine, while 32 with no history of migraine were included as controls. Study results appear in the Journal of Manipulative and Physiological Therapeutics.

Signs and symptoms of TMJ were observed in 54 percent of the control participants without migraine, 80 percent of participants with episodic migraine, and 100 percent of those with chronic migraine.

Florencio believes central sensitization may explain the association between the frequency of migraine attacks and the severity of TMJ. “The repetition of migraine attacks may increase sensitivity to pain,” she said.

“Our hypothesis is that migraine acts as a factor that predisposes patients to TMJ. On the other hand, TMJ can be considered a potential perpetuating factor for migraine because it acts as a constant nociceptive input that contributes to maintaining central sensitization and abnormal pain processes.”

Nociceptive pain is caused by a painful stimulus on special nerve endings called nociceptors and is usually described as a sharp, aching, or throbbing pain. The researchers explain that migraine and TMJ have very similar pathological mechanisms.

Migraine affects 15 percent of the general population, and progression to the chronic form is expected in about 2.5 percent of migraine sufferers. TMJ is stress-related as much as it has to do with muscle overload.

Patients display joint symptoms — such as joint pain, reduced jaw movement, clicking or popping of the temporomandibular joint — but also develop a muscular condition, including muscle pain and fatigue, and/or radiating face and neck pain.

Although people who suffer from migraine are predisposed to have TMJ, people with TMJ will not necessarily have migraine.

“Migraine patients are more likely to have signs and symptoms of TMJ, but the reverse is not true. There are cases of patients with severe TMJ who don’t present with migraine,” said Débora Grossi, the lead researcher for the study.

The researchers believe that TMJ may increase the frequency and severity of migraine attacks, even though it does not directly cause migraine.

“We do know migraine isn’t caused by TMJ,” Florencio said. “Migraine is a neurological disease with multifactorial causes, whereas TMJ, like cervicalgia — neck pain — and other musculoskeletal disorders, is a series of factors that intensify the sensitivity of migraine sufferers. Having TMJ may worsen one’s migraine attacks in terms of both severity and frequency.”

The journal article concludes that an examination of TMJ signs and symptoms should be clinically conducted in patients with migraine.

“Our findings show the association with TMJ exists but is less frequent in patients with rare or episodic migraine,” Grossi said.

“This information alone should change the way clinicians examine patients with migraine. If migraine sufferers tend to have more severe TMJ, then health professionals should assess such patients specifically in terms of possible signs and symptoms of TMJ.”

Source: University of São Paulo/EuerkAlert

Posted by Patricia Adams