"Floating knee" injuries: ipsilateral fractures of the femur and tibia.

Ipsilateral fractures of the femur and tibia have been called "floating knee" injuries and may include combinations of diaphyseal, metaphyseal, and intra-articular fractures. These are often high-energy injuries and most frequently occur in the polytrauma patient. Many of these fractures are open, with associated vascular injuries. Surgical stabilization of both fractures and early mobilization of the patient and the extremity produce the best clinical outcomes. The use of a radiolucent operating room table and the introduction of retrograde intramedullary fixation of femoral fractures have facilitated surgical stabilization of some floating-knee fracture patterns. Although treatment planning for each fracture in the extremity should be considered individually to achieve the optimal result, the effect of that decision must be considered in light of the overall injury status of the entire extremity. Collateral ligament and meniscal injuries may also be associated with this fracture complex. Complications (such as compartment syndrome, loss of knee motion, failure to diagnose knee ligament injury, and the need for amputation) are not infrequent. Better results and fewer complications are observed when both fractures are diaphyseal than when one or both are intra-articular.