Can atlas spina bifida-occulta be a cause of cervicogenic headaches?

Cervicogenic headaches are a nosologic entity recently recognized. In our common practice, we have noticed a relative frequency of the atlas spina-bifida occulta during the brain CT scan realized for headaches without cranio-encephalic causes or any other anomaly of the upper cervical region. The aim of this study was to determine a possible connection between cervicogenic headaches (CEH) and atlas spina-bifida occulta. A 2 years prospective and descriptive study in 20 black patients having an atlas spina-bifida occulta diagnosed with a brain CT scan. The mean age of the patients was 43.17 ± 18.35 years (extremes: 24 and 72 years). A light female predominance was noticed (sex-ratio = 1.5). The frequency of symptomatic spina-bifida was 1.72 % (17 cases). The mean age at onset was 31.84 years. The pain was sub-occipital in 14 cases, occipital in 8 cases, bilateral in 12 cases and unilateral in 5 cases. The mean duration of the attacks was 72 ± 24 h and the pain intensity was moderate (16 cases); mean and range were 3.6 and 3–6. The frequency of attacks varied between 1 per 7 months (n = 2) and 2 per week (n = 1) in those with non-daily headache. One attack per 5–7 weeks was the most commonly occurring attack frequency. The pain was reproduced by the pressure of the occipital region or upper cervical in 15 cases. The mean number of criteria was five and there was a strong positive correlation between criteria and CEH (χ(2) = 45.57; V = 0.62). The associated signs were photophobia and nausea in one case each. Indomethacin, Ergotamine and/or Sumatriptan were without any antalgic effect in 16 cases. Pain ceased after an anesthetic blockade of C2 (16 cases). The results show that atlas spina-bifida occulta is not involved in CEH pure form genesis. On a small sample, the atlas spina-bifida seems to be a cause of CEH associated with headache and disorders of the neck.