Referred Pain After Painful Stimulation of the Greater Occipital Nerve in Humans: Evidence of Convergence of Cervical Afferences on Trigeminal Nuclei

Abstract

Cranial sensory innervation is supplied mainly by the trigeminal nerves and by the first cervical nerves. Excitatory and inhibitory interactions among those nerve roots may occur in a mechanism called nociceptive convergence, leading to loss of somato-sensory spatial specificity. Three volunteers in an experimental trial had sterile water injected over their greater occipital nerve on one side of the neck. Pain intensity was evaluated 10, 30 and 120 s after the injection. Two of the patients reported intense pain. Trigeminal autonomic features, suggestive of parasympathetic activation, were seen associated with trigeminally distributed pain. These data add to and reinforce previous evidence of convergence of cervical afferents on the trigeminal sensory circuit.

Non–hypothalamic cluster headache: the role of the greater occipital nerve in cluster headache pathogenesis

“…Electrophysiological studies suggest that there is a convergence of dural and cervical afferents in the GON and then onto the trigeminocervical complex in humans [4]. GON stimulation has been shown to cause frontal head pain in humans [5]. In addition, Piovesan et al [5] documented a patient who after GON stimulation developed not only pain in the head area innervated by the ophthalmic division of the trigeminal nerve but also ipsilateral conjunctival injection and lacrimation.…”

Raeder's syndrome after embolization of a giant intracavernous carotid artery aneurysm: pathophysiological considerations

“…Connections between such stru c t u- res and aff e rent convergents to the spinal trigeminal nucleus 31 would account for pain referred to the ipsilateral periorbital area.…”

Surgical Interventions for Cluster Headache, Including Implanted Stimulators

“…Physiological studies in animals have pointed at convergence of trigeminal (trigeminal nucleus caudalis) and upper cervical (dorsal horns C1-C3) nociceptive information, and thus a loss of spatial specificity at the level of the second order neurons of what is collectively called the TCC (Bartsch and Goadsby 2003). The concept of a TCC is furthermore supported by human experimental evidence (Piovesan et al 2001;Busch et al 2006). This functional continuum between occipital and trigeminal nociceptive input is important to understand how occipital neurostimulation could be effective in CH, characterized by activation of the trigeminovascular system.…”