The AO Spine framework is the globally accepted standard for classifying cervical fractures based on CT and MRI findings.
Surgical Stability Probe
Input the primary morphological mechanism observed on imaging to establish the AO Spine Type and determine biomechanical stability.
Guidelines & Evidence
Clinical Details
Section 1
When to Use
When to Use
Standardized communication of subaxial (C3-C7) cervical bone and ligamentous injuries.
Directing mechanical surgical planning (e.g., A/B vs C types).
Section 2
Literature
Development
The AO Spine foundation updated and unified global spine trauma classification to create a common language. By creating a hierarchy of A (Compression, bone only), B (Tension band, ligaments failing), and C (Translation, complete mechanical dissociation), they allowed rapid severity triage.
Section 3
Pearls/Pitfalls
The Hierarchy of Danger
The classification is hierarchical. Type C dominates Type B, and Type B dominates Type A. If a patient has a burst fracture (Type A4) but also has a torn posterior ligamentous complex allowing the spine to flex opening (Type B2), the injury is classified as a B2. The highest grade dictates the surgical necessity.
Section 4
Evidence Appraisal
Primary Reference
AOSpine subaxial cervical spine injury classification system
Vaccaro AR et al. • Eur Spine J. 2016;25(7):2173-84
