Spine iSAWE 16

Question

A 33 year old man dives into a shallow pool and strikes his head. He has neck pain and no neurological deficit.

Spine iSAWE 16, axial and coronal CT of the upper cervical spine
Axial and coronal CT of the upper cervical spine. Image by Michael Utz, Shadab Khan, Daniel O’Connor & Stephen Meyers, Wikimedia Commons, CC BY 4.0.
  1. Describe the CT and the mechanism.
  2. How do you assess stability?
  3. Outline management.

Answer

CT and mechanism

  • Burst fracture of the ring of C1 with anterior and posterior arch fractures (Jefferson fracture)
  • Axial load drives the occipital condyles into the lateral masses
  • Fragments spread outwards, so neurological injury is uncommon

Stability

  • Transverse atlantal ligament integrity decides stability
  • Combined lateral mass overhang over 6.9 mm on the open mouth view (Spence rule) suggests TAL rupture
  • MRI shows TAL rupture directly
  • Dickman classification, type I midsubstance tear, type II bony avulsion
  • ADI over 3 mm in adults suggests instability
  • Exclude associated C2 fractures and vertebral artery injury (CTA)

Management

  • Intact TAL, rigid collar for 8 to 12 weeks
  • Dickman type II avulsions may heal in a halo or collar
  • Dickman type I midsubstance tears need C1 to C2 fusion
  • Halo for unstable injuries where fusion is declined
  • Occiput to C2 fusion if lateral masses are destroyed

Related pages

Author Contributions

Orthofracs team

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.