Mason-Johnston Radial Head Fracture Classification
Mason-Johnston classification (Mason 1954; type IV added Johnston 1962) of a radial head fracture — the fracture pattern of a fracture of the head of the radius.
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Example
- Mason type
- III — comminuted, entire radial head
Result: Mason type III: comminuted fracture of the entire radial head; classically excision or radial-head replacement; a more severe pattern.
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What the result means
- Type I / II
- Nondisplaced / minimally displaced, no mechanical block (I); displaced (> 2 mm) partial-articular fracture, may block motion (II).
- Type III
- Comminuted fracture of the entire radial head; usually not reconstructable. A more severe pattern.
- Type IV
- Radial head fracture with an associated elbow dislocation (Johnston). A more severe pattern.
What you enter
- Mason type
How this is calculated
Mason ML. Some observations on fractures of the head of the radius with a review of one hundred cases. Br J Surg. 1954;42(172):123-132. Type IV: Johnston GW. Ulster Med J. 1962;31:51-56. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.