Blunt neck trauma

Pearls

• Suspect vascular damage to the cord if discrepancy between neuro deficit and level of spinal column injury
• Down syndome predisposes to atlanto-occipital dislocation; RA predisposes to C2 transverse ligament rupture
• Cord injury is more likely if both the anterior (vertebral bodies) and posterior (spinal canal) columns are disrupted

Atlanto-occipital dislocation

• Evaluate with the Powers ratio
  • Ratio of BC:OA > 1 suggests anterior subluxation
  • BC = distance between basion and midpoint of C2 post laminar line
  • OA = Distance between opisthion and ant arch of C2

C1 Fractures

• Burst (Jefferson)
  • Highly unstable
  • Axial loading transmitted through occipital condyles to the lateral masses
    • Results in fx of the ant and post arches
    • Stability is determined by whether or not the transverse ligament is disrupted
  • Suspect if:
    • Lateral xray: Increase in the predental space between C1 and the dens
      • Predental space greater than 3 mm in adults or 5 mm in children is abnormal
    • Odontoid xray: Masses of C1 to lie lateral to the outer margins of the articular pillars of C2
  • If either of the above findings on xray then obtain CT c-spine
• Posterior Arch
  • Must ensure that you are not confusing this with a burst fx!
    • Odontoid view must be normal
  • Due to forced neck extension
  • Vertical fx line through posterior arch seen on lateral xray
  • Stable (b/c anterior arch and transverse ligament are unaffected)

C2 Fractures

• Traumatic spondylolysis ("Hangman's Fx")
  • Unstable
  • Forced extension of an already extended neck
  • Spinal cord damage is often minimal (the AP diamter of the neural canal is greatest at C2)
• Odontoid Fracture
  • Type I
    • Above the transverse ligament
    • Stable
  • Type II
    • At the base where it attaches to C2
    • Unstable
    • Most common
  • Type III
    • Extension of the fracture through the upper portion of C2

Cervical Fractures

• Anterior Wedge Fracture
  • Unstable if:
    • Loss of over half of vertebral height OR
    • Multiple adjacent wedge fractures
• Flexion Teardrop Fracture
  • Unstable
  • Associated with acute anterior cervical cord syndrome
  • Displacement of a teardrop shaped fragment of the antero-interior portion of the superior vertebra
    • Severe flexion > vertebral body collides with the one below
• Extension Teardrop Fracture
  • Unstable
  • Abrupt neck extension > anterior longitudinal ligament avulses anteroinferior corner
    • Avulsed fragment is greater in height than width (contrast with flexion teardrop)
  • Often occurs at C5-C7 associated with diving accidents
    • Associated with central cord syndrome
• Spinous Process Fracture (Clay Shoveler's)
  • Stable
  • Isolated fracture of one of the spinous processes of the lower cervical vertebrae
• Burst Fracture
  • Posteriorly displaced fracture fragment may impinge on the cord
  • Axial compression > nucleus pulposus forced into vertebral body
  • Imaging
    • Lateral xray - Comminuted body and loss of vertebral height
    • AP xray - Vertical fracture of the body

Facet Dislocations

• Bilateral
  • Unstable
  • Complete spinal cord injury most often results
  • Disruption of the annulus fibrosus and the ant longitudinal ligament > ant displacement of the spine
• Unilateral
  • Stable
  • Spinal cord injury rarely occurs

Source

UpToDate