Ulnar Styloid Fracture with Distal Radioulnar Joint Instability

A distal radius fracture with associated ulnar styloid fracture may place the patient at higher risk for distal radioulnar joint (DRUJ) instability. With anatomical reduction and volar plate fixation of the distal radius fracture, the ulnar styloid fracture is often indirectly reduced and the DRUJ remains stable. It has been shown that ulnar styloid fractures or its nonunion does not affect the outcome with adequate reduction and fixation of the distal radius fracture. However, large ulnar styloid base fractures or displacement over 2 mm may require open reduction and fixation of the ulnar styloid fracture to achieve DRUJ stability due to proximity of major DRUJ stabilizing ligaments. DRUJ instability may lead to chronic pain, decreased range of motion, and need for further salvage procedures for relief. The most important guiding principle is to evaluate DRUJ stability following distal radius fixation routinely to determine whether or not to address concomitant ulnar styloid fracture. If the DRUJ remains stable after anatomical fixation of the distal radius, ulnar styloid fixation is rarely required. If the DRUJ remains unstable, we would recommend open reduction and internal fixation of ulnar styloid fracture to achieve stability and reduce the risk of long-term problems.