This rare injury is usually caused by a high-energy fall onto an outstretched hand. Occasionally it is caused by a violent direct blow.
The injury is associated with local tenderness over the distal forearm, specifically over the radius. Local swelling is usual. Visible deformity is often present; this is usually posterior angulation (apex anterior), but may be anterior angulation.
Check for tenderness over the distal radioulnar joint (Galeazzi variant).
Posterior angulated (apex anterior) radial fractures tend to produce an anterior displacement of the ulnar head. Anteriorly angulated fractures produce a posterior displacement of the distal ulna.