Question 29

Regarding cervical spinal cord injury (SCI).
a) Define the following terms:
i. Complete SCI
ii. Neurological level of injury (20% marks)

b) List four incomplete syndromes related to SCI. (20% marks)

c) Compare and contrast the features of a complete SCI and central cord syndrome at neurological level of C4. (60% marks)

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College answer

Whilst most candidates scored reasonably well in this question, many candidates answered the question with a to narrow a focus on the neurological findings, rather than the broader features e.g. prognosis/other organ dysfunctions/interventions when asked to compare and contrast. This aspect of the question was which was worth 60% of the marks


To defend the trainees, "features" here would immediately make the stressed exam candidate think of "clinical features", especially as the stem goes on to mention a "neurological level". Most reasonable people would agree that it would have been fairer to explicitly ask for "prognosis/other organ dysfunctions/interventions" if this is what was expected.

The definitions below come from the 2019 revision of the ASIA classification statement


Complete spinal cord injury:  an absence of any sensory and motor function in the lowest sacral segments (light touch, pin prick at S4-5, DAP, and voluntary anal contraction) (i.e., no “sacral sparing”).

Neurological level of injury: the most caudal segment of the spinal cord with normal sensory and antigravity motor function on both sides of the body, provided that there is normal (intact) sensory and motor function rostrally.

b) Four incomplete syndromes: only four are asked for, but there are in fact five listed by ASIA, and probably more that are theoretically possible.

  1. Central cord syndrome
  2. Brown-Séquard syndrome
  3. Anterior cord syndrome
  4. Posterior cord syndrome
  5. Cauda equina syndrome
  6. Conus medullaris syndrome

c) To contrast "the features of a complete SCI and central cord syndrome at neurological level of C4" would benefit from a table format:

Complete injury at C4 Central cord syndrome at C4
Neurological features
  • Tetraplegia
  • Preserved shoulder shrug (trapezius)
  • Sensation below the clavicles is absent
  • Phrenic nerve paralysis: loss of diaphragmatic innervation
  • Sacral sensation preserved
  • Greater weakness in the upper limbs than in the lower limbs.
  • Cape-like distribution of sensory deficit (pain and temperature)
  • Priapism
  • Preserved sacral sensation
  • Trauma 
  • Infarction
  • Abscess
  • Tumour
  • Hyperextension injury with pre-existing canal stenosis
  • Ependymoma
  • Syringomyelia
Physiological consequences and organ complications
  • Autonomic dysreflexia
  • Poor gut motility
  • Hyperaldosteronism
  • Insulin resistance
  • Suxamethonium sensitivity
  • Hypercalcemia, osteoporosis and renal calculi
  • Hypothermia of spinal cord injury
  • Upper limb DVT
  • Upper limb spasticity
  • Neuropathic pain
  • Bladder dysfunction (urinary retention)
Necessary interventions
  • Long term ventilation
  • Tracheostomy
  • Psychological intervention
  • PEG
  • Suprapubic urinary catheter
  • Posterior decompression may be useful to relieve some of the features
  • Baclofen or Botox for spasticity
  • High mortality (double that of paraplegia, 8% vs 4%)
  • Reduced life expectancy
  • Overall, good prognosis
  • up to 80% of patients will regain some independence


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.

Brooks, Nathaniel P. "Central cord syndrome." Neurosurgery Clinics 28.1 (2017): 41-47.

Walters, Beverly C., et al. "Guidelines for the management of acute cervical spine and spinal cord injuries: 2013 update." Neurosurgery 60.CN_suppl_1 (2013): 82-91.

Middleton, James W., et al. "Life expectancy after spinal cord injury: a 50-year study." Spinal cord 50.11 (2012): 803-811.