Complex Fractures of the Distal Femur

Abstract

The most common classification system used for fractures of the distal femur is the ASIF (Association for Internal Fixation)/OTA (Orthopaedic Trauma Association) system. ASIF/OTA 33-C3 distal femur fracture (complete articular fracture with severe comminution) is characterized by complex articular involvement and is often accompanied by a very short distal femur segment, small osteochondral fragments, and high-energy soft tissue disruption. Current fixation strategies include external fixation, plating, and retrograde locked intramedullary (IM) nail. In the treatment of the 33-C3 distal femur fractures malunion, loss of fixation, need for supplemental fixation, and need for bone grafting are common. The surgical management of complex fractures of the distal femur must be based on classification, patient selection, and preoperative planning. The use of either a retrograde locked IM nail or plate fixation in complex fractures of the distal femur must be based on orthopedic surgeon experience. Concerning what is the best type of plate fixation, the current trend is to use locking plates. However, the rates of deep infection and nonunion are similar in locking plates with that of traditional plate fixation (blade plate, DCS – dynamic condylar screw). External fixation is usually reserved for open fractures of the distal femur with bone loss, vascular injury, associated severe soft tissue injuries, or extensive comminution. Monolateral external fixation without spanning the knee and circular or ring fixators can be used. Malunion, loss of fixation, need for supplemental fixation, and need for bone grafting are common in the treatment of the 33-C3 distal femur fracture. In periprosthetic fractures of the distal femur, retrograde IM nailing and locking plates appear to be more successful than nonlocking plates. Distal femur endoprosthesis should be considered in patients with advanced age and poor bone quality who require early mobilization.