CERVICOGENIC HEADACHE - A CRITICAL-REVIEW OF THE CURRENT DIAGNOSTIC-CRITERIA

Opinions are divided on the use of the term cervicogenic headache (CGH ) in cases with no evidence of cervical damage. According to Sjaastad et al. (1990), CGH is diagnosed from three features: (1) unilateral he adache triggered by head/neck movements or posture; (2) unilateral hea dache triggered by pressure on the neck; (3) unilateral headache sprea ding to the neck and the homolateral shoulder/arm. Other characteristi cs are not essential for CGH diagnosis, including pain improvement aft er greater occipital nerve (GON)/C2 block. However, other authors give different definitions of CGH, and this may explain why reported frequ encies for this headache vary so widely. In this paper we critically r eview the major diagnostic criteria of Sjaastad et al. for CGH in the light of clinical studies conducted at our institute and other literat ure findings. In a study of 500 headaches we found only two patients w ith unilateral headache triggered by head/ neck movements or posture, and no cases of neck pressure-induced headache. No clear-cut criteria are given in the literature for differentiating CGH trigger points fro m myofascial trigger points. In another study of 440 primary headache patients we found that in the unilateral long-lasting headache group ( 64 migraines and 10 tension-type headaches), a pain involving the occi put/neck was present in 30 migraine and seven tension headache patient s; thus, according to the CGH major criteria, 10% (30/307) of 'migrain es' and 7% (7/96) of 'tension headaches' could be diagnosed as CGH. Ho wever, one cannot exclude that the association of unilateral pain with posterior irradiation is due to the high prevalence of migraine, tens ion-type headache and chronic neck pain. The relation between CGH and whip-lash injury has been put in doubt by a recent study which found n o difference in headache frequency between trauma and control groups a nd reported no specific headache pattern in the trauma group. Other re ports suggest that, when it occurs, CGH usually disappears within a ye ar of whip-lash, throwing doubt on the appropriateness of surgery for post-traumatic CGH. The lack of specificity of GON/C2 block as a treat ment for CGH adds further difficulties to the diagnosis of this headac he. We conclude that, although neck structures play a role in the path ophysiology of some headaches, clinical patterns indicating a neck-hea dache relationship have still not been adequately defined. We believe that further rigorous studies are needed to definitively confirm the v alidity of CGH as a nosological entity. (C) 1998 International Associa tion for the Study of Pain. Published by Elsevier Science B.V.