Headache after whiplash: a historical cohort study outside the medico-legal context

Headache is frequently reported as a chronic complaint after whiplash traumas. Criteria have been presented, but it has not been validated whether any specific headache type emerges after a trauma with whiplash mechanism. In a questionnaire-based historical cohort design, 202 adult Lithuanian individuals were interviewed 1-3 years after experiencing a rear-end car collision. The questionnaire was designed so that a diagnosis of migraine and tension-type headache in accordance with the International Headache Society criteria could be made. "Possible cervicogenic headache" was diagnosed according to Sjaastad et al.'s minimal criteria. The diagnostic panorama in those with traumas was compared with that of an age- and sex-matched control group. The introductory questions did not reveal differences in headache frequencies between the traumatized and control groups (p = 0.60). The prevalence of migraine and tension-type headache (both episodic and chronic) was also similar. A higher frequency of possible cervicogenic headache was observed in the traumatized group (10 vs 5), but the difference was not statistically significant (p = 0.28). Sixteen patients in the accident group had headache > 15 days per month, 11 of the 16 had similar complaints before the trauma, while 5 had worsened headache as compared to (the recollected headache) before the trauma. None of the patients with possible cervicogenic headache reported increased headache after the accident. Accordingly, the present results obtained outside the medico-legal context do not confirm that a specific headache pattern emerges 1-3 years after a rear-end car collision.