Cervical Afferents and Primary Headache: The Indefensible Perspective

In the late 1990s, when I was attempting to undertake a PhD investigating the role of cervical afferents in Primary Headache conditions, I approached several medical model authorities for support because I thought that for research in this area to have any credibility, it would need to be sponsored by such an authority—how naive!

Of course, this never happened because the typical response was, ‘Well, we don’t know what causes migraines (true), but it cannot come from the neck.’   Circa 2024, I have been constantly bemused by the perspective that upper cervical afferents might contribute to a Primary Headache but do not play a causal role.

In the past two decades, there has been a significant increase in (great) research investigating cervical afferents in primary headache conditions by our manual therapy colleagues. Unfortunately, most have been published in non-medical journals, but summarily and disappointingly, the conclusions are timid, toeing the line with the medical model – I get that.  Maintaining the status quo for credibility and publications is important (but it doesn’t help our clinical colleagues and those with headache, irrespective of which label you want to put on it).

This is perplexing when what defines a Primary Headache is a headache resulting from unknown pathophysiology… if it is unknown, how can a possibility be dismissed outright without due consideration?  This perspective is fundamentally indefensible.

My PhD was completed in 2016; the seminal study was published in 2014 (Headache). This study, using the nociceptive blink reflex to monitor the trigeminocervical complex (TCC) during reproduction and resolution of typical head pain in migraineurs, demonstrated DEsensitisation of the TCC, mirroring research involving the triptans and blockade of the greater occipital nerve. Furthermore, scrutiny of this research indicates that desensitisation was not the result of activating endogenous inhibitory systems, psychosocial factors or placebo.

Given that the underlying disorder is sensitisation of the TCC in migraine, this finding that a cervical intervention modulated (likely at the spinal level) the very core of the migraine process was unpalatable for some reviewers, delaying publication.

I was advised to tone down or understate the significance of this finding. This was difficult for me because this was an affirmation of my clinical experience since 1991 – I acquiesced and paid for it!

Three esteemed international authorities examined my PhD, and while minimal changes were suggested and made, one examiner’s strongest comment was that I had downplayed the significance of this research.

Anyway, colleagues who attended my courses in Europe in the early 2000s are now researching the reproduction and resolution of typical head pain in Primary Headache conditions and the role of cervical afferents.

Thank you for your continued advocacy of the role of cervical afferents in Primary Headache. Yes… it’s tough. Maintaining your integrity but changing ‘Well, we don’t know what causes migraines (true), but it cannot come from the neck’ will not happen from understating your research – let’s not keep what you know clinically and instinctively a secret anymore.

Be bold, but ‘not rock the boat’. I understand that – it’s a fine line! You need to preserve your research facilities and remain credible.

Good Luck!