AO Spine Subaxial Cervical Spine Injury Classification
AO Spine subaxial cervical spine injury classification assembles the code from four axes.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Morphology
- A1 - compression of one endplate, posterior wall intact
- Facet injury
- F4 - pathologic subluxation, or a perched or dislocated facet
- Neurological status
- N0 - neurologically intact
- Bilateral facet injury of the same type
- Yes
Result: AO Spine subaxial cervical A1 F4BL N0: a barely injured vertebral body with bilateral dislocated facets.
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Morphology
- Facet injury
- Neurological status
- Bilateral facet injury of the same type (BL)
- M1 - posterior capsuloligamentous complex injury without complete disruption
- M2 - critical disc herniation
- M3 - stiffening or metabolic bone disease (DISH, ankylosing spondylitis, OPLL, OLF)
- M4 - vertebral artery injury
How this is calculated
Vaccaro AR, Koerner JD, Radcliff KE, et al. AOSpine subaxial cervical spine injury classification system. Eur Spine J. 2016;25(7):2173-2184. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.