Internal fixation of ulnar shaft fractures restores the length of the ulna and congruency of the distal radioulnar joint (DRUJ). Oblique and spiral fractures may be fixed with a lag screw and a protection plate. If the distal ulnar fragment is short, a locking plate, or mini condylar plate may be used.
In transverse ulnar fractures (“defense fractures”) a pre-contoured compression plate is used.
These fractures are not usually associated with DRUJ injuries, but it is good practice to assess the joint after fixation in all cases.