Anterior Spinal Artery Syndrome Associated With Cervical Spinal Stenosis

ABSTRACT

BACKGROUND: The anterior spinal artery infarction constitutes a classical syndrome of vascular myelopathy. The causes of the anterior spinal artery syndrome are various, but most episode probably occur as the result of atherosclerosis or dissection of the aorta and its branches. However, few cases reported developed with spinal structural abnormalities. CASE A 65-year-old man presented with sudden paraparesis. There was no evidence of hypertension, diabetes and smoking. Motor weakness was more prominent on the left side and progressed. Loss of pain and temperature senses were shown at the level of 71 with preservation of touch, joint perception and vibration senses. The DTR's of legs were depressed and extensor toe signs were presented. A C-spine MRI showed high signal intensity on 72 weighted image and low signal on 71 weighted image(C6-71) with cervical spinal stenosis at the C4-C7 spinal level and mild cervical disc protrusion (C6-C7, C7-T1). After three months later, follow up cervical MRI showed somewhat decreased size of high signal intensity on 72 weighted image and more prominent low signal on 71 image. DISCUSSION: In our case, we could not find any usual cause of anterior spinal artery infarction. However only cervical spinal stenosis associated with mild cervical disc protrusion was present. In stenotic cervical canal, the anterior spinal artery can be more vulnerable to extrinsic compression and the infarction may early develop with insignificant trigger event, such as disc protrusion. We concluded that the ischemic change of anterior two thirds of cervical spinal cord might develop due to the compression of the anterior spinal artery by cervical stenosis and mild cervical intervertebral disc protrusion.