Contrary to previous studies, neck pain is a symptom of migraine only, not the result of an underlying muscle dysfunction that triggers migraine attacks, according to a recent article published in The Journal of Headache and Pain.
The study sought to weigh in on the scientific debate regarding neck pain in migraineurs, and whether neck muscle dysfunction could be a trigger for migraine attacks or is merely a symptom.
Investigators recruited 102 participants (43 episodic migraine, 31 chronic migraine, and 28 healthy controls) and used surface electromyography to record muscle tension of the trapezius during 15 blocks of stressful experimental conditions alternated with relaxation periods. Examples of experimental conditions include counting backwards from 100 by differences of 9, and pressing 1 foot on a body weight scale to reach and hold at least 27 kg for 30 seconds.
Two surface channels at either side of the upper trapezius muscle were used to measure electromyography, and the resultant data were analyzed by an expert blind to the diagnosis. All groups showed an increase in activity in the bilateral trapezius during the experimental periods of both mental and physical stress.
The differences between the mean electromyography increases shown during experimental conditions compared with relaxation blocks were negligible, except for during the first mental stress period (counting backward by 9s). In this initial test, the healthy control groups only experienced a 4.75% increase in muscle tension, the muscle tension of participants with episodic migraines increased by 17.39%, and the tension of participants with chronic migraines increased by 28.61%.
During the relaxation periods, both healthy controls and participants with migraine took the same amount of time to return to resting electromyography levels.
Study limitations include the testing of only the trapezius muscle, so that electromyography levels of neck tension could not be compared with tension in other areas, such as the jaw. In addition, needle electromyography is more precise than the surface recordings used here, but needle recordings would not have been workable within the study parameters.
These findings indicate perceived neck tension and pain experienced before or during migraine attacks “should be regarded as a symptom of the attack and not as a trapezius muscle dysfunction triggering an attack. T his conclusion was based on the evaluation of the trapezius muscle; whether it can be generalized to all neck muscles remains to be investigated by future studies.”
Reference
Luedtke K, Mehnert J, May A. Altered muscle activity during rest and during mental or physical activity is not a trait symptom of migraine – a neck muscle EMG study [published online March 20, 2018]. J Headache Pain. doi: 10.1186/s10194-018-0851-5