Radial head fracture Type 4 is defined as what?

• A. Displaced.
• B. Non-displaced.
• C. Comminuted.
• D. Associated with elbow dislocation.

Answer: (D)

In the commonly used Mason classification for radial head fractures, Type IV denotes a radial head fracture that occurs with an elbow dislocation. This combination signals joint instability and a more complex injury than an isolated radial head fracture. Recognizing the dislocation matters for management, since it requires reduction of the elbow and careful assessment for accompanying ligament injuries and other associated fractures (such as the coronoid process). The other forms describe the fracture pattern alone—non-displaced, displaced with a single fragment, or comminuted without elbow dislocation—so the defining feature of this type is the accompanying elbow dislocation.