A Case of Vertebrobasilar Insufficiency caused by Cervical Spondylosisat C5/6 on Head Rotation to the Left : Its Pathogenesis and Surgical Treatment

Abstract

We report a case of vertebrobasilar insufficiency caused by cervical spondylosis at C5/6 on head rotation to the left. A 41-year-old man who had congenital C2/3 fusion, and underwent C6/7 anterior fusion after disc herniation developed vertebrobasilar insufficiency that occurred when he rotated his head to the left. Cervical spine X-ray revealed C4/5 instability and spondylotic change at C5/6 on the left. MRI showed lateral displacement of the vertebral artery due to osteophyte formation and a protruded disc; displacement of this artery increased markedly with head rotation to the left. Vertebral angiogram showed tortuosity and stenotic change at the C5/6 level, and the stenosis increased to slow the blood flow upon head rotation to the left. We performed anterior fusion with autograft after resection of the osteophyte and herniated disc on the left, and the patient's ischemic epiosodes disappeared. We discuss the mechanics of injury leading to the stroke and the treatment modality.