Vertebrobasilar ischemia after neck motion.

BACKGROUND. Vertebrobasilar ischemic strokes may occur after chiropractic manipulation of the cervical spine or, less often, after spontaneous and abrupt head movement. SUMMARY OF REVIEW. We describe three such cases of vertebrobasilar ischemic strokes and review 36 other reported cases. CONCLUSIONS. We give evidence that 1) the population at risk cannot be identified a priori in the vast majority of cases; 2) symptoms may develop after many uneventful manipulations; 3) clinical syndromes consist of occipital lobe (5%), cerebellar (8%), locked-in (8%), Wallenberg's (28%), other brain stem (49%), and unclassifiable (2%); 4) mortality or very severe long-term impairment occurs in 28% of cases; 5) the development of transient neurological symptoms during previous manipulations, the presence of known or suspected ligament laxity, and, if known, the presence of a vertebral artery terminating in posterior inferior cerebellar artery should always contraindicate any chiropractic neck maneuver; and 6) the pathogenetic mechanism involves vertebral artery dissection at the atlantoaxial joint with intimal tear, intramural bleeding, or pseudoaneurysm that can lead to thrombosis or embolism.