Anderson-Montesano (Occipital Condyle Fracture)
The Anderson-Montesano classification of occipital condyle fractures, by fracture morphology and mechanism, 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
- Anderson-Montesano type
- III - alar-ligament avulsion, potentially unstable
Result: Anderson-Montesano type III: avulsion fracture of the occipital condyle at the alar ligament insertion.
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What the result means
- Type I
- Impacted, comminuted from axial loading; typically stable.
- Type II
- Extending from a basioccipital / skull-base fracture; usually stable.
- Type III
- Alar-ligament avulsion; potentially unstable.
What you enter
- Anderson-Montesano type
How this is calculated
Anderson PA, Montesano PX. Morphology and treatment of occipital condyle fractures. Spine (Phila Pa 1976). 1988;13(7):731-736. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.