Blunt neck trauma

Revision as of 20:22, 12 September 2011 by Jswartz (talk | contribs)

Background

  • Suspect vascular damage to 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 ant (vertebral bodies) AND post (spinal canal) columns are disrupted
  • If find injury consider CT C-spine, x-ray rest of spine
  • Penetrating injury rarely results in unstable fx

Atlanto-occipital Disassociation

  • Unstable
  • Often associated w/ brain injury
  • 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)

  • Unstable
  • Axial loading transmitted through occipital condyles to the lateral masses
    • Results in fx of the ant AND post arches
    • Degree of instability determined by whether or not the transverse ligament is disrupted
  • Suspect disruption if:
    • Lateral x-ray: 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 lie lateral to outer margins of articular pillars of C2
    • If either of the above findings on xray then obtain CT c-spine

Anterior Arch

  • Stable

Posterior Arch

  • Stable (b/c anterior arch and transverse ligament are unaffected)
  • 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

C2 Fractures

Odontoid (dens) Fracture

  • Only stable if fx confined to avulsion of the tip (superior to transverse ligament)
  • Frequently involves other cervical spine injuries
  • 25% a/w neurologic injury
  • Types
    • Type I
      • Fx above transverse ligament
      • Stable
    • Type II
      • Fx at base of odontoid process where it attaches to C2
      • Unstable
    • Type III
      • Extension of the fx through upper portion of body of C2
      • Unstable

Traumatic Spondylolisthesis ("Hangman's Fx")

  • Unstable
  • Fracture of both C2 pedicles leads to C2 displacing anteriorly on C3
  • Seen in MVA and diving accidents (not in suicidal hangings)
    • Forced extension of an already extended neck
  • Spinal cord damage is often minimal (diameter of neural canal is greatest at C2)

C3-C7 Fractures

Anterior Wedge Fracture

  • Only unstable if lose over half of vertebral height OR multiple adjacent wedge fractures

Flexion Teardrop Fracture

  • Unstable
  • Severe flexion > vertebral body colliding with the one below
    • Displacement of teardrop shaped fragment of antero-inferior portion of sup vertebra
    • Leads to disruption of posterior longitudinal ligament
  • Associated with acute anterior cervical cord syndrome

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

  • Unstable if:
    • Associated neurologic deficits
    • Loss of >50% of vertebral body height
    • >20 degrees of spinal angulation
    • Compromise of >50% of spinal canal
    • Axial compression > nucleus pulposus forced into vertebral body
  • Imaging
    • Lateral x-ray - Comminuted body and loss of vertebral height
    • AP x-ray - Vertical fracture of the body

Facet Dislocations

Bilateral

  • Unstable
  • Complete spinal cord injury most often results
  • Disruption of annulus fibrosus and ant longitudinal ligament > ant displacement of spine
  • Imaging
    • Lateral xray: vertebral body will be displaced >50% of its width

Unilateral

  • Stable
  • Imaging
    • Lateral x-ray: vertebral body will be displaced <50% of its width
    • Anterior x-ray: affected spinous process points toward side that is dislocated
  • Spinal cord injury rarely occurs

See Also

Source

  • UpToDate
  • Tintinalli's