Following repair of a thoracoabdominal aortic aneurysm, a patient wakes with flaccid paraplegia and complete loss of pain and temperature sensation below the T8 level, while light touch, vibration and joint position sense are fully preserved. What is the explanation for this pattern?
- A Infarction in the territory of the anterior spinal artery ✓
- B Infarction of the posterior half of the spinal cord
- C Acute demyelination of the corticospinal tracts
- D Compression of the cauda equina by an expanding haematoma
Correct answer: A. Infarction in the territory of the anterior spinal artery
Explanation
The anterior spinal artery supplies the anterior two thirds of the cord, including corticospinal and spinothalamic tracts, while the paired posterior spinal arteries supply the dorsal columns. Occlusion during aortic surgery therefore causes anterior cord syndrome: loss of motor plus pain and temperature with preserved vibration and proprioception. Among incomplete cord syndromes it carries the poorest prognosis for recovery. Cauda equina compression would not spare dorsal column modalities in this segmental fashion.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.