This patient had a spinal cord infarct, a “stroke of the spinal cord” if you will. Her initial MRI was read as a long segment, expansile cord signal abnormality extending from the thoracic cord through the conus. Because this extendedhigher in the thoracic spine over the next two days, it was thought to be an infarct.
Spinal cord infarcts are similar to strokes in the brain except much more likely to cause pain. They occur suddenly as opposed to the other diagnoses in the differential diagnosis: Guillan Barre, mass lesions, transverse myelitis, viral myelitis and infection. The spinal cord infarct can be preceded by spinal cord TIAs first described in 1911 by Dejerine as transient paraparesis .
The primary vascular supply for the posterior third of the spinal cord is the posterior spinal artery and the anterior spinal artery supplies theanterior two thirds. The anterior spinal arteries have only a few feeders in the cervical region and only one in the thoracic; the artery of Adamkiewicz. The thoracic cord is especially vulnerable to insults and can be injured with a dissection of the aorta, aortic surgery or atherosclerosis.
If the anterior spinal artery is compromised sudden pain in the backfollows in minutes with bilateral flaccid weakness and sensory loss. Pain and temperature are disproportionately impaired while position and vibration may be spared. If the lesion is small and affects tissue fartherst away from the occluded artery a central cord syndrome may develop.
The location of the infarct is different depending on the cause. Aortic sneursyms and their repair are most likely to cause infarct in the thoracic cord. AVMs and spinal artery embolism can occur at any level. Other causes of infarct include : vasculitis, complications of cervical nerve root injection atherosclerosis ( with diabetes being a risk factor) and decompression sickness.
Teaching point: If a patient tells you they are ready for a turkey sandwich; do not assume they are ready to go home. Remember the mantra of the ED: Assume nothing, trust no one and expect sabotage. In large series the initial MRI can be negative.
Patients course: The patient remained paraplegic. Her course was complicated in the hospital by difficulty controlling her blood sugar. Her LP showed elevated protein at 151 , 5 nucleated cells and 551 rbcs with neg cultures. She was treated with two weeks of antibiotics IVbecause of “the severity of her deficit”.
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Masson C, Pruvo J, Meder J, Cordonnier C, et al. Spinal cord infarction 2004 J Neurol Neurosurgery Psychiatry 75:1431-35.
Brouwers P, Kottink E, Simon M. Acervical anerior spinal artery syndrome after diagnostic blackage of the R C6 nerve root. Pain 2001, Vol 91, issue 3,: 397-399.