Fri12November0729PM 3

A 74-year-old man presents for a rigid oesophagoscopy for dysphagia.

He has severe osteoarthritis of his cervical spine with limited mobility in rotation and flexion-extension. He has had no previous neurological symptoms or signs.

Anaesthesia for the procedure was complicated by a difficult intubation (Cormack-Lehane 3) but was achieved using a gum elastic bougie. Once the patient had recovered from anaesthesia it was noted that he had motor weakness of upper and lower limbs (disproportionately greater in the upper than the lower). It was also noted that he had bladder dysfunction and varying degrees of sensory loss below C5.

Which one of the following incomplete spinal cord lesions is this patient most likely to have sustained?

(Please select 1 option)

Posterior spinal artery thrombosis

Cauda equina syndrome

Anterior spinal artery thrombosis

Central cord syndrome Correct

Brown-Sequard syndrome

Explanation

Central cord syndrome: Is the most common incomplete spinal cord lesion. The spinal cord is injured in central grey matter and results in proportionally greater loss of motor function to upper extremities than lower extremities with variable sensory sparing;

The nerve fibres responsible for lower extremity motor and sensory functions are located in the most peripheral part of the cord, whereas fibres controlling the upper extremity and voluntary bowel and bladder function are more centrally located; the sacral tracts are positioned on the periphery of the cord and are usually spared from injury.

This type of injury is associated with cervical spondylosis and extension in the elderly or hyperextension injury in middle age.

Anterior spinal artery infarction: The anterior spinal artery is a single long anastomotic channel that lies at the mouth of the anterior central sulcus and supplies the circulation to the anterior two thirds of the spinal cord. Eight to ten unpaired anterior medullary arteries are branches of the larger afferent aorta and vertebral and iliac arteries. These feed into the anterior spinal arteries.

The largest anterior medullary artery, the great anterior medullary artery of Adamkiewicz, which is susceptible to occlusion with neurologic deficit, is located at the lumbar enlargement, usually at L2 on the left side (but may be at any point from T8 to L2).

Infarction of the anterior spinal artery causes motor paralysis below the level of the lesion due to interruption of the corticospinal tract, and loss of pain and temperature sensation at and below the level of the lesion. Proprioception and vibratory sensation is preserved, as it is in the dorsal side of the spinal cord.

Aortic disease has produced spinal infarction in a variety of situations including dissecting aneurysm; aortic surgery, especially with aortic cross-clamping above the renal artery, atherosclerotic embolisation; aortography; and aortic thrombosis.

Brown-Sequard syndrome is characterised by ipsilateral upper motor neurone paralysis and loss of proprioception, with contralateral loss of pain and temperature sensation. Causes include trauma, neoplasm and multiple sclerosis.

Spinal cord infarctions are rare, especially at the cervical level and in the posterior spinal artery territory. Moreover, this diagnosis is difficult to establish as the clinical picture varies. Even if sensory patterns appear as cardinal signs, their distribution can be very variable.

Cauda equina syndrome:The spinal cord ends at L1 and L2 at which point a bundle of nerves travel downwards through the lumbar and sacral vertebrae (L1-5 and S1-4). Injury to these nerves will cause partial or complete loss of movement and sensation in this distribution.

Answer Statistics

1

6%

2

3%

3

10%

4

76%

5

7%

Times answered: 250