Forearm fractures are often the result of indirect mechanisms, such as a fall onto an outstretched hand, sporting activities, etc. More details about their clinical and radiographic examination see here .
Often these radial fractures are located where the cross-section of the radius is circular. At this level of the radius the main stress is torsional, because the bending loads are carried by the ulna.
1. Intact wedge
Radial shaft fractures where the wedge is intact are classified as AO/OTA 2R2B2.
2. Fragmented wedge
Radial shaft fractures where the wedge is fragmented are classified as AO/OTA 2R2B3.
3. With dislocation of the distal radioulnar joint (Galeazzi)
In a Galeazzi fracture-dislocation the displaced radial shaft fracture is associated with a dislocation of the ulnar head at the distal radioulnar joint (DRUJ).
These are classified by AO/OTA, according to the morphology of the radial fracture, with qualifier (g). For example, the illustration shows a 2R2B3(g).