30/06/2023
Trigeminocervical Complex: The Trigeminocervical Complex (TCC) refers to the relationship between the upper neck, TMJ (Jaw), and trigeminal nerve.
Physio Meets Science’s analysis considers the relationship(s) between headaches, neck pain and the trigeminocervical complex.
“A compelling theory explaining the link between neck pain and migraine or tensionä-type headache (TTH) involves activation of the trigeminocervical complex, consisting of trigeminal nucleus caudalis and dorsal horns of C1–C3, which receives convergent input from trigeminal nerves and upper cervical roots (s.Fig., https://www.mskscienceandpractice.com/article/S2468-7812%2823%2900089-9/fulltext).
📌 This line of reasoning is supported by several lines of evidence:
👉 Preclinical models suggest that nociceptive input from pericranial muscles and dura mater can activate this complex (https://pubmed.ncbi.nlm.nih.gov/12077000/, https://pubmed.ncbi.nlm.nih.gov/12821523/, https://pubmed.ncbi.nlm.nih.gov/12946290/; https://pubmed.ncbi.nlm.nih.gov/24703540/).
👉For instance, sensory neurons of dorsal root ganglion at the C2 to C3 have been shown to cross the bony canal and large foramens of the skull to innervate pericranial muscles and dura (https://pubmed.ncbi.nlm.nih.gov/30622169/). It is proposed that stimulation of the posterior dural nociceptors intracranially leads to induction of headache and neck pain, while central sensitization may be the reason behind neck pain that occurs after the onset of headache (https://pubmed.ncbi.nlm.nih.gov/3200599/; https://pubmed.ncbi.nlm.nih.gov/30622169/; https://pubmed.ncbi.nlm.nih.gov/7239900/).
👉 Stimulation of C1 evokes frontal and periorbital pain in people with migraine, while the same stimulation only triggered occipital and cervical pain in people free from migraine https://pubmed.ncbi.nlm.nih.gov/23424170/).
👉 Interestingly, injection of hypertonic saline into neck muscles in healthy controls elicited pain in cervical structures as well as headache (https://pubmed.ncbi.nlm.nih.gov/16674766/). Thus, cervical-neuronal-activation might be an important source of pain during migraine and TTH attack.
👉 Al-Khazali et al. therefore suggest coexistent neck pain to reduce the pain threshold via peripheral and central mechanisms in people with migraine and TTH. In addition, pericranial tenderness may not only be a complication of migraine or TTH but may also contribute to their onset. In support, people with migraine and lower back pain had increased risk of central sensitization and peripheral sensitivity, compared to healthy controls (https://pubmed.ncbi.nlm.nih.gov/29349847/).”
- Another most excellent analysis by Physio Meets Science
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