Walking past Watson’s office, Watson’s colleague notices the door is open. “Do you have a moment, Watson?” “Yes, of course.”
“I know we have discussed your views of unilateral head pain and its behavior, but a colleague of mine has a bilateral headache, which he believes is coming from his neck. However, his doctor has diagnosed tension headache and believes that his neck symptoms are not causative to his headache. Why is this?”
The Dilemma of Bilateral Head Pain
“Well, as discussed before, neck-related cervicogenic headache (CGH) is unilateral and side-locked. His bilateral headache rules out cervical involvement” explains Watson. “Furthermore, the ICHD-3 perspective is that because tension headache is a primary headache (pathophysiology unknown), cervical afferents cannot be involved – I have vented my frustration previously – this perspective is both illogical and indefensible. What is even more frustrating is that the conclusion from credible manual therapy research investigating primary headache, demonstrating cervical involvement, is that cervical afferents cannot be causative because the headache being investigated is a primary headache!”
“I am presuming then that your view is upper cervical musculoskeletal misbehaviour can be responsible for bilateral head pain?” “Yes,” is Watson’s emphatic reply.
The Acquiescence of ICHD-3
“Interestingly, over the past 30 years, I have noticed a slowly developing acquiescence around the side-locked unilaterality CGH diagnostic criterion to allow a ‘soft’ bilaterality, i.e., with a side-locked unilateral predominance. This is evidenced in a recent publication on CGH,1 and I quote… ‘Unilateral pain is the usual criterion…, although it may be bilateral if severe.’ (p. 3). I think the ICHD-3 is unclear around this key diagnostic criterion.”
“I am interested in that article. Can you send me a link?” “Yes, of course.” “The link to the abstract is on the way to your inbox as we speak, and is titled, ‘Cervicogenic headache – How to recognize and treat‘ 1.”
“But while my perspective is that symmetrical bilateral headache can result from upper cervical musculoskeletal misbehaviour, a bilateral presentation could result from an underlying medical condition, e.g., intracranial hypotension—so a bilateral presentation doesn’t necessarily confirm CGH,” comes Watson’s cautionary comment.
“So, where does that leave bilateral headache?” enquires Watson’s colleague.
The Behaviour of Bilaterality Confirming Upper Cervical Musculoskeletal Misbehaviour
“I am glad you asked”, Watson replies eagerly and continues confidently, “Just as there are behaviours of unilateral head pain which confirm musculoskeletal misbehaviour as the origin of head pain, there are behaviours of bilateral head pain which do the same. For example, bilateral head pain is one in which there is alternating unilaterality in terms of intensity, i.e., assume that there is bilateral temporal pain, where sometimes there is increased intensity on the right and, on other occasions, increased intensity on the left. Whilst a rare presentation, this behaviour represents upper cervical musculoskeletal misbehaviour – what I refer to as ‘Bilateral Alternating Unilaterality’.”
“This is intriguing”, replies Watson’s colleague. “Are there any other examples?”
“Yes, where bilateral head pain gradually transitions into, whilst remaining bilateral, predominately one-sided or unilateral; ‘Transitory Bilaterality’. This behaviour is a clear-cut manifestation of upper cervical dysfunction”.
“I am seeing my colleague tomorrow, so I’ll ask if any of these behaviours occur”.
“Well, there is another expression of bilateral head pain suggesting musculoskeletal misbehaviour: bilateral temporal headache, which is always predominately unilaterally on one side, and never the other; ‘Bilateral side-locked unilaterality’.”
Bilaterality of Head Pain and CGH: At the Cross Roads?
“That’s great”, comes Watson’s colleague’s grateful reply.
“My pleasure. I have to attend a meeting, but before I go, I want to draw attention to the publication1 I mentioned earlier. Respectfully, I have several issues with this exposition. Still, about head pain behaviour, there is an ambiguous statement about CGH that needs clarifying, and that is, “Also, cases of ‘unilaterality on two sides may be acceptable.’ (p. 3). I am unsure how to interpret this… are the authors referring to alternating unilateral head pain? If so, why not describe it unambiguously?” enquires Watson.
“Anyway, perhaps we can discuss this and another contemporary publication’s2 perspective on other aspects of CHG next time.”
References
- Piovesan EJ, Utiumi MAT, Grossi DB. Cervicogenic headache – How to recognize and treat. Best Pract Res Clin Rheumatol. Feb 21 2024:101931.
- Antonaci F, Inan LE. Headache and neck. Cephalalgia. Apr 2021;41(4):438-442.
