Traynelis Classification (Atlanto-Occipital Dislocation)
The Traynelis classification of traumatic atlanto-occipital dislocation (AOD), by the direction of occiput displacement relative to the atlas, types I/II/III.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Traynelis type
- II - longitudinal distraction (vertical separation)
Result: Traynelis type II: longitudinal distraction (vertical separation) of the occiput from the atlas.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Type I
- Anterior displacement of the occiput relative to the atlas.
- Type II
- Longitudinal distraction (vertical separation) of the occiput from the atlas.
- Type III
- Posterior displacement of the occiput relative to the atlas.
What you enter
- Traynelis type
How this is calculated
Traynelis VC, Marano GD, Dunker RO, Kaufman HH. Traumatic atlanto-occipital dislocation. Case report. J Neurosurg. 1986;65(6):863-870. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.