Spine iSAWE 8

Question

An 84 year old woman falls from standing and has neck pain. She is neurologically intact.

Spine iSAWE 8, sagittal ct of the cervical spine
Sagittal CT of the cervical spine. Image by James Heilman, MD, Wikimedia Commons, CC BY-SA 3.0.
  1. How is this injury classified?
  2. What are the management options?
  3. What factors affect union?

Answer

Anderson and D’Alonzo classification

TypeDescription
ITip avulsion above the transverse ligament, stable
IIFracture at the base of the dens, highest nonunion rate
IIIExtends into the C2 body, unites well

Management

  • Hard collar for type I, type III and frail patients with type II
  • Halo vest is poorly tolerated in the elderly, with pneumonia and death
  • Posterior C1 to C2 fusion for unstable or displaced type II
  • Anterior odontoid screw for type II with a favourable fracture line, good bone and an intact transverse ligament
  • A stable fibrous union is an acceptable outcome in the very elderly

Factors for nonunion

  • Displacement over 5 mm
  • Posterior displacement
  • Angulation over 10 degrees
  • Increasing age and smoking

Related pages

Author Contributions

Orthofracs team

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