I've mentioned the complexity of headaches several times. Don't believe me? A quick skim of this article covering just one of the potential etiologies should suffice to convince.
The pathogenesis of migraine headache is poorly understood but the trigeminovascular system seems to play an important role in it. The trigeminal nucleus caudalis is sensitised by noxious sensory stimuli, often from convergent afferents originating from a variety of tissues. In this paper, we review evidence to support the view that the cervical muscles play a role in the pathogenesis of the migraine headache as well by facilitating the mechanism of central sensitisation
By:Elliot Shevel1 and Egilius H. Spierings