Bigliani Classification (Acromion Morphology)

The Bigliani classification of acromion morphology, by the shape of the acromial undersurface on the supraspinatus-outlet view, 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

Bigliani type
II - curved acromion

Result: Bigliani type II: a curved acromion, the undersurface paralleling the humeral head.

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What the result means

Type I
Flat acromial undersurface.
Type II
Curved acromial undersurface (paralleling the humeral head).
Type III
Hooked acromion (anterior hook); most associated with impingement and cuff tears.

What you enter

  • Bigliani type
How this is calculated

Bigliani LU, Morrison DS, April EW. The morphology of the acromion and its relationship to rotator cuff tears. Orthop Trans. 1986;10:228. Search PubMed for this source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.