Denis Classification (Sacral Fracture)
Denis classification (Denis 1988) of a sacral fracture (zones I-III), by the relationship of the fracture line to the sacral foramina and central canal - the standard anatomic zoning that predicts neurologic-injury risk.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Denis zone
- Zone III - central canal (medial to the foramina)
Result: Denis zone III: the central sacral canal, medial to the foramina; the highest neurologic-injury rate, with bowel, bladder, and sexual dysfunction.
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What the result means
- Zone I
- Alar, lateral to the foramina; the lowest neurologic-injury rate (~6%, usually L5 or sciatic).
- Zone II
- Through the foramina; intermediate neurologic-injury rate (~28%, L5/S1/S2 radiculopathy).
- Zone III
- Central sacral canal, medial to the foramina; highest rate, with bowel/bladder/sexual dysfunction.
What you enter
- Denis zone
How this is calculated
Denis F, Davis S, Comfort T. Sacral fractures: an important problem. Retrospective analysis of 236 cases. Clin Orthop Relat Res. 1988;(227):67-81. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.