Question 22

Angoff score
5.80
Highest mark
9.2
Pass rate
??
Other SAQs in this topic:
Other SAQs in this paper:

For each of the following syndromes list the clinical findings and one likely mechanism of injury:
a) Anterior spinal cord syndrome. (2.5 marks)
b) Hemi cord/ “Brown-Sequard” syndrome. (2.5 marks)
c) Lateral medullary syndrome. (3 marks)
d) Central cord syndrome. (2 marks)

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College answer

Syllabus topic/section:

2.1.13 Trauma Intensive care / Spinal Cord injury: L1

Discussion:  

This is a repeat question which overall was moderately well answered by most candidates. Clarity and specificity are required when describing neurological findings. Correctly identifying contralateral vs ipsilateral findings and detailing mechanisms of injury is important in this question. Lower marks were related to omission of bowel/bladder clinical findings. Candidates are advised to revise lateral medullary and central cord syndrome in their preparation.

Discussion

This was a repeat of Question 15 from the first paper of 2015, except that time, the candidates were asked for two mechanisms.  The Important spinal cord injury syndromes chapter from the Required Reading section contains a table of spinal cord injury syndromes, which is reproduced below to simplify revision.

In brief:

  • The anterior cord contains motor tracts; anterior cord damage results in motor paralysis with preserved sensation.
  • The posterior cord contains predominantly sensory tracts, and damage there will result in predominantly sensory loss, with preserved movement.
  • The lateral cord contains ipsilateral motor/ proprioception  and contralateral pain / temperature fibers. Damage there will leave the damaged side paralysed, and the opposite side anaesthetised.
  • The central cord contains motor fibers from the upper limb (lower limb fibers are more peripheral). Damage there will cause upper limb paralysis.
  • The Cauda Equina governs lower limbs, bladder and bowel. Saddle anaesthesia is the key feature.
Causes and Characteristic Features of Spinal Cord Syndromes

Syndrome

Characteristic features

Causes

There are some causes which are generic for all these syndromes, and they will not be repeated in each box. These are:

  • Trauma
  • Infarction
  • Abscess
  • Tumour or metastatic compression
  • Haematoma
  • AVM/haemorrhage

Any of these can cause any of the spinal syndromes, anywhere. Instead of these, the causes listed below are the characteristic pathological processes which usually give rise to a specific spinal cord syndrome, eg. anterior spinal artery occlusion causing anterior spinal syndrome.

Cord transection
  • Lost bilateral motor
  • Flaccid areflexia
  • Lost bilateral sensory
  • Usually trauma
  • Transverse Myelitis

Cord hemisection
  • Lost ipsilateral motor
  • Lost ipsilateral proprioception and vibration
  • Lost ipsilateral light touch
  • Lost contralateral pain and temperature
  • Penetrating spinal injury
  • Radiation inury
  • Spinal metastases

Anterior cord injury
  • Preserved bilateral proproception, light touch, vibration
  • Lost bilateral pain, temperature, touch
  • Lost bilateral motor control

Interruption of the blood supply to the anterior spinal cord:

  • Aortic dissection
  • IABP complication

Posterior cord injury
  • Lost proprioception,  light touch, vibration
  • Other sensation preserved bilaterally
  • Preserved power bilaterally
  • Ataxia results
  • Hyperextension injury
  • Posterior spinal artery injury
  • Tertiary syphilis
  • Friedrich's ataxia
  • Subacute degeneration (Vitamin B12 deficiency)
  • Atlantoaxial subluxation

Central cord syndrome
  • Sacral sensation preserved
  • Greater weakness in the upper limbs than in the lower limbs.
  • Hyperextension injury with pre-existing canal stenosis
  • Ependymoma
  • Syringomyelia

Conus medullaris syndrome
  • symmetrical paraplegia
  • Mixed upper and lower motor neuron
    findings
  • The same sort of pathologies can give rise either to a cauda equina syndrome or a conus medullaris syndrome; the difference is the level.

Cauda Equina syndrome
  • asymmetrical, lower motor neuron lower limb weakness
  • saddle area paraesthesia
  • bladder and bowel areflexia

References

Rupp, Rüdiger, et al. "International standards for neurological classification of spinal cord injury: revised 2019." Topics in spinal cord injury rehabilitation 27.2 (2021): 1-22.

Wagner, Robert, and Andy Jagoda. "Spinal cord syndromes." Emergency medicine clinics of North America 15.3 (1997): 699-711.

Lin, Vernon W., et al. "Spinal Cord and Cauda Equina Syndromes." (2003).

Maynard, Frederick M., et al. "International standards for neurological and functional classification of spinal cord injury." Spinal cord 35.5 (1997): 266-274.

Hayes, Keith C., et al. "Classifying incomplete spinal cord injury syndromes: algorithms based on the International Standards for Neurological and Functional Classification of Spinal Cord Injury Patients." Archives of physical medicine and rehabilitation 81.5 (2000): 644-652.

McDonald, John W., and Cristina Sadowsky. "Spinal-cord injury." The Lancet 359.9304 (2002): 417-425.

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