Spinal Imaging
21/5/11
Diagnostic Imaging in Critical Care
- CT is the best way to image the spine for bony injuries (will miss 6% of discoligamentous injuries)
- if suspected soft tissue or spinal cord injury -> patient requires an MRI
CHECK LIST
- space between anterior arch of C1 and peg (< 3mm in adults, < 5mm in children)
- posterior cortex of C1
- anterior cortex of peg
- spinolaminar line of C1-C3
- anterior and posterior spinolaminar lines
- bodies height and alignment
- facets aligned
- no subluxation or widening
- no prevertebral swelling
- discs intact
- no soft tissue swelling
- space between arch and peg < 3mm
- no significant rotation (< 15 degrees OK)
- no soft tissue swelling
- integrity of ring
- symmetry of peg and lateral masses
- facets aligned
- height of vertebral bodies
- discs and facet joints aligned
PATHOLOGIES
- AP: narrowed disc space
- lateral: anterior and posterior vertebral body lines and spinolaminar lines disrupted > 50%, angulation
- surgical emergency: requires urgent traction or immediate open reduction if patient is neurological normal or has a incomplete spinal injury.
Jeremy Fernando (2011)

- AP: spinous processes below the dislocation do not align with those above it, interspinous processes widened.
- lateral: facet joint dislocation, 25% forward shift
- oblique: facet join dislocation better seen
- traction can be used but if unsuccessful -> emergency surgery seldom required.
- I: tip of odontoid
- II: junction of dens and body
- III: extending into body of C2
- can be potentially fatal -> injury of craniocervical junction or brain stem
- I: anterior subluxation
- II: vertical distraction of atlanto-occipital joint > 2mm
- III: posterior dislocation
- I: blunting of the anterior-superior vertebral margin
- II: beak-like appearance to the anterior vertebral body with loss of anterior vertebral height and an oblique contour.
- III: fracture extending from the anterior surface of the vertebral body into the disc space.
- IV: posterior displacement of the inferoposterior aspect of the vertebral body <3mm.
- V: displacement of the vertebrae below is > 3mm
- I: abnormal widening of the disc space (disruption of the anterior longitudinal ligament and disc)
- II: posterior ligaments are disrupted and the cephalad vertebrae are displaced into the spinal canal.
- damage to vertebral arch but the body of the affected vertebra remains intact.
- can be unilateral or bilateral
- can involve the pedicle, articular or lamina (or a combination of these)
- body fracture (loss of height)
- retropulsion into the vertebral canal
- I: central fracture of either the superior of inferior endplate with a ‘cupping deformity’
- II: both endplates are involved
- III: vertebral body fragmented with fragments displaced in multiple directions.
Jeremy Fernando (2011)

- anterior extensive ossification along vertebral bodies.
- if come with neck pain -> require an MRI as cord is very susceptible given small canal.
- flexion-distraction injury
- widening of the interspinous interval
- fracture line through the body
- high incidence of a intra-abdominal injury
TRICKS AND TRAPS
- look for fractures lines -> if lines smooth think congenital problem
- deficiency in posterior arch of C1
- C1 ring symmetry will be maintained
- odontoideum: dens separated from the body of C2
- deficiency of anterior arch of C1
Jeremy Fernando (2011)