Minimally invasive internal fixation of distal femur fractures.

Fractures of the distal femur remain a daunting challenge. Since 1970, operative treatment has been recommended. Unfortunately, it is fraught with complications, and techniques have been developed to limit incidence of non-union, infection and stiffness. A soft-tissue friendly approach is the key point, with minimally invasive surgery as the ultimate goal: its biological and anatomical advantages have been demonstrated, but clinical studies have been less convincing, being based on historical series. At present, retrograde nailing and minimally invasive percutaneous plate osteosynthesis (ideally by locking plate) are the two main techniques. Unfortunately, reports tend to compare implants rather than operative techniques, hindering solid conclusions. Lastly, the delineation of "distal femur fracture" is quite variable, sometimes situated well above the AO epiphyseal square. Meta-analyses find almost no difference between the two implants in minimally invasive procedures. The main advantage of the plate is its versatility, whereas nailing can be impossible in case of certain hip or knee prostheses, compound articular fracture or medullary canal obstruction by fixation material (nail, stem, screw, etc.). The role of arthroscopy is limited. Only a few case reports describe its use in reduction of epiphyseal fracture. In the last analysis, the surgeon's experience is more relevant to outcome than any particular implant.