Extraarticular fracture of the ulnar styloid process

This is an avulsion fracture of the ulnar styloid.
The ulnar styloid may be avulsed at its tip, or through its base (basi-styloid fracture).

These are classified by AO/OTA as 2U3A1.1 if the fracture is at the tip, or 2U3A1.2 if the fracture is at the base.

The level of avulsion has implications for the integrity of the attachment of the triangular fibrocartilage complex (TFCC) and the stability of the distal radioulnar joint (DRUJ).