Rotational obstructions of the vertebral artery at the atlantoaxial joint.
Two patients with vertebrobasilar ischemia are described in whom angiography demonstrated obstruction of one vertebral artery at the C1-2 level on rotation of the head. The possible anatomical explanation and physiological significance of this finding are discussed.
D001368:Axis, Cervical Vertebra; D002560:Cerebrovascular Circulation; D001270:Cervical Atlas; D006257:Head; D006801:Humans; D007511:Ischemia / Q000209:etiology*; D007596:Joints; D008297:Male; D008875:Middle Aged; D009068:Movement; D011859:Radiography; D012399:Rotation; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*