- 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
- 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
Bilateral facet joint dislocation
- 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.
Unilateral facet joint dislocation
- 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
Compressive flexion injury
- 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
Distraction extension injury
- 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.
Compressive extension injury
- 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)
Vertebral compression injury
- 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.
Diffuse idiopathic skeletal hyperostosis (DISH)
- 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
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.
After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.
He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE. He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.
His one great achievement is being the father of three amazing children.
On Twitter, he is @precordialthump.