Cervicogenic headaches: a critical review.
BACKGROUND
The notion that headaches may originate from disorders of the cervical spine and can be relieved by treatments directed at the neck is gaining recognition among headache clinicians but is often neglected in the spine literature.


OBJECTIVE
To review and summarize the literature on cervicogenic headaches in the following areas: historical perspective, diagnostic criteria, epidemiology, pathogenesis, differential diagnosis, and treatment.


METHODS
A systematic literature review of cervicogenic headache was performed.


METHODS
Three computerized medical databases (Medline, Cumulative Index to Nursing and Allied Health Literature [CINAHL], Mantis) were searched for the terms "cervicogenic" and "headache." After cross-referencing, we retrieved 164 unique citations; 48 citations were added from other sources, for a total of 212 citations, although all were not used.


RESULTS
Hilton described the concept of headaches originating from the cervical spine in 1860. In 1983 Sjaastad introduced the term "cervicogenic headache" (CGH). Diagnostic criteria have been established by several expert groups, with agreement that these headaches start in the neck or occipital region and are associated with tenderness of cervical paraspinal tissues. Prevalence estimates range from 0.4% to 2.5% of the general population to 15% to 20% of patients with chronic headaches. CGH affects patients with a mean age of 42.9 years, has a 4:1 female disposition, and tends to be chronic. Almost any pathology affecting the cervical spine has been implicated in the genesis of CGH as a result of convergence of sensory input from the cervical structures within the spinal nucleus of the trigeminal nerve. The main differential diagnoses are tension type headache and migraine headache, with considerable overlap in symptoms and findings between these conditions. No specific pathology has been noted on imaging or diagnostic studies which correlates with CGH. CGH seems unresponsive to common headache medication. Small, noncontrolled case series have reported moderate success with surgery and injections. A few randomized controlled trials and a number of case series support the use of cervical manipulation, transcutaneous electrical nerve stimulation, and botulinum toxin injection.


CONCLUSIONS
There remains considerable controversy and confusion on all matters pertaining to the topic of CGH. However, the amount of interest in the topic is growing, and it is anticipated that further research will help to clarify the theory, diagnosis, and treatment options for patients with CGH. Until then, it is essential that clinicians maintain an open, cautious, and critical approach to the literature on cervicogenic headaches.
Haldeman
S
S
Department of Neurology, University of California, Irvine, Medical Center, 101 The City Drive South, Orange, CA 92868, USA. HaldemanMD@aol.com
Dagenais
S
S
D002574:Cervical Vertebrae; D006261:Headache / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D006801:Humans; D013122:Spinal Diseases / Q000150:complications* / Q000175:diagnosis / Q000628:therapy