Extensor/flexor ratio of neck muscle strength and electromyographic activity of individuals with migraine: a cross-sectional study

Abstract

Neck pain is considered a common characteristic of migraine attacks. The relationship between neck pain and migraine can be explained by central sensitization of the trigeminocervical complex, where superior cervical afferents and the trigeminal nerve converge. However, few studies have evaluated motor control of cervical muscles in individuals with migraine. Thus, the purpose of the present study was to determine the extensor/flexor ratio of neck muscle strength and electromyographic activity during a test of maximal voluntary isometric contraction and craniocervical flexion in individuals with migraine and individuals without history of migraine or other headaches. Fifty-two women with the disease and 52 women with neither a history of migraine nor neck pain, between 18 and 55 years old, were included in the study. The electromyographic activities of the sternocleidomastoid, anterior scalene, splenius capitis, and upper trapezius muscles were evaluated during a test of maximal voluntary isometric contraction and craniocervical flexion. The migraine group presented lower flexor muscle strength and a higher extensor/flexor muscle strength ratio than the control group. In addition, the migraine group showed a reduced electromyographic extensor/flexor muscle ratio during maximal voluntary isometric contraction in flexion. The results demonstrated worse performance in the craniocervical flexion test of the migraine group and a lower electromyographic ratio of extensor/flexor neck muscles in the last stage of the test. Altogether, the migraine group presented an imbalance in cervical muscles verified not only during force production, but also during muscle activity. These slides can be retrieved under Electronic Supplementary Material.