The etiology of cervical artery dissection.

The etiology of cervical artery dissection (CAD) is unclear, although a number of risk factors have been reported to be associated with the condition. On rare occasions, patients experience CAD after cervical spine manipulation, making knowledge about the cervical arteries, the predisposing factors, and the pathogenesis of the condition of interest to chiropractors. This commentary reports on the relevant anatomy of the cervical arteries, developmental features of CAD, epidemiology of the condition, and mechanisms of dissection. The analysis of CAD risk factors is confusing, however, because many people are exposed to mechanical events and known pathophysiological associations without ever experiencing dissection. No cause-and-effect relationship has been established between cervical spine manipulation and CAD, but it seems that cervical manipulation may be capable of triggering dissection in a susceptible patient or contributing to the evolution of an already existing CAD. Despite the many risk factors that have been proposed as possible causes of CAD, it is still unknown which of them actually predispose patients to CAD after cervical spine manipulation.