Mayo Classification (Olecranon Fracture)

Mayo classification of olecranon fractures (Morrey 1993): three radiographic factors set a type code IA-IIIB.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Displacement
Displaced (about 3 mm or more)
Ulnohumeral joint stability (required when displaced)
Stable (ulnohumeral joint congruent, ligaments intact)
Comminution
Comminuted (subtype B)

Result: Mayo type IIB

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What the result means

Types
I undisplaced; II displaced with the ulnohumeral joint stable; III displaced with the joint unstable (fracture-dislocation).
Subtype
A = noncomminuted, B = comminuted, giving six codes IA-IIIB. Displacement separates I from II/III; ulnohumeral stability separates II from III.

What you enter

  • Displacement (undisplaced <3mm, or displaced)
  • Ulnohumeral joint stability (required when displaced): stable or unstable
  • Comminution (noncomminuted = A, comminuted = B)
How this is calculated

Morrey BF, Adams RA. Fractures of the proximal ulna and olecranon. In: Morrey BF, ed. The Elbow and Its Disorders. 2nd ed. Philadelphia: WB Saunders; 1993:405-428. (Reviewed: Sullivan CW, Desai K. Classifications in Brief: Mayo Classification of Olecranon Fractures. Clin Orthop Relat Res. 2019.) Read the 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.