Distal radius fractures: patterns of articular fragmentation.

Distal radius articular fractures principally result from the die-punch mechanism of injury that leads to consistent patterns of articular disruption with readily identifiable radiographic signs of instability and reducibility. In the vast majority of articular fractures, prompt recognition of these key radiographic features serves as a sound basis for optimal management. Whereas the type I stable injury can be managed by short-term immobilization, the most frequently encountered type II unstable die-punch fracture requires stabilization provided by external fixation, frequently coupled with percutaneous internal fixation, to maintain an accurate reduction. Restoration of articular congruity in an irreducible type IIB dorsal die-punch fracture, in contrast, can only be accomplished by open treatment, usually comprising a limited exposure for reduction and internal fixation of the radiocarpal articular surface, supplementary external fixation, and adjunctive iliac bone grafting. The irreducible type IIB articular fracture with volar displacement is most suitable for stabilization by plate and screw fixation; however, in patients with excessive comminution, Kirshner wires provide a satisfactory alternative method of fixation. The type III spike fragment is secured with either small screws or wires in conjunction with closed or limited open articular restitution and appropriate nerve and tendon surgery. The irreducible type IV fracture demonstrating wide separation of articular components always requires extensive open treatment for restoration of articular congruity as well as repair of associated skeletal and soft tissue injuries. In the type V explosion injury, provisional stabilization employing, external fixation provides a sturdy framework for critical revascularization or resurfacing procedures and serves to maintain radial alignment before definitive articular reconstruction. In more severe injuries, early detection and repair of frequent periarticular injuries are essential for a favorable recovery. In those fractures requiring open reduction with internal fixation, supplementary external fixation and iliac bone grafting have proved to be increasingly beneficial adjuvants to management. In all cases, preservation of articular congruity with precise restoration of key medial fragments is the principal prerequisite for a successful outcome.