[A case of cerebral infarction in young adult resulting in thrombotic occlusion of vertebral artery due to repeated contact stimulation of cervical rotation accompanied to systemic malformations such as atlantoaxial subluxation and atlas dysplasia].

A 23-year-old man admitted to our hospital with headache and dysarthria. Head MRI showed multiple acute cerebral infarctions in the right posterior circulation. Atlantoaxial dislocation, atlas dysplasia and thrombotic occlusion of right vertebral artery (VA), and blood flow disruption due to cervical rotation was observed. The axial dental process bordered to the right VA, and repeated contact stimulation by cervical rotation may cause intimal damage resulting in thrombotic occlusion. In this case, various systemic malformations such as atrial septal defect, atlas posterior arch hypoplasia, bovine left common carotid bifurcation malformation, double inferior vena cava and horseshoe kidney may have been congenital syndromes. Atlantoaxial dislocation may be an important and under-recognized cause of stroke in young adults.