Vertebrobasilar artery insufficiency in rheumatoid atlantoaxial subluxation.

Cervical myelopathy has become commonly recognized as a complication of rheumatoid atlantoaxial subluxation. A small group of patients with atlantoaxial subluxation may have intermittent symptoms associated with change of head position and which are due to vertebral artery compression. Two such cases are reported, one with necropsy findings of infarction in the area supplied by the vertebrobasilar system. The pathogenesis of the symptomatology and infarction is discussed.