Retrograde Nail vs Double Plating for Distal Femoral Extra and Simple Articular Fractures With Metaphyseal Comminution

Fractures of the distal femur are complex injuries that constitute a challenge to the orthopedic surgeon. It represents about 7% of all the femoral fractures. It usually occurs during high energy trauma in younger patients and frequently is associated with concomitant injuries. In elderly patients with severe osteopenia might sustain solitary distal femoral fractures from minor trauma such as simple fall.

The challenge for the surgeons remains in the balance of providing stable fixation to support physiological loading until union while allowing necessary micro motion for callus formation. So, significant advances have been made in treatment of these fractures in the past few decades. It is recognized that operative fixation with the ability to maintain anatomical reduction of the joint surface, restoring axial ligament and early range of motion presents clear advantages over closed means of treatment.

There are principles that have been proposed for the treatment of these fractures which include anatomical reduction of distal femoral articular surface, stable internal fixation, minimal soft tissue stripping and early active mobilization.

Comminuted distal femur fractures are associated with extensive soft tissue injuries like injuries to Ligaments of the knee, injuries to the surrounding muscles additional challenges like extensive bone loss, loss of soft tissue coating and these fractures produce very unfavorable conditions for fracture union. As the long list of challenges a surgeon has to face while treating such injuries, the functional outcomes are usually not satisfactory. These fractures are associated with high rates of malunion, nonunion and infection.

Intramedullary (IM) nail offers a potential biomechanical advantage over side plates and screws because the Intramedullary location results in less stress over the implant and better stress distribution than with eccentric side plate and screws. They have the potential for load shearing. Their use involves minimal soft tissue injury, short operative time, limited perioperative blood loss, and ability to mobilize patients early.

Retrograde intramedullary nail fixation is an accepted and often preferred alternative to distal locking plates for the treatment of distal femur fractures and fractures with simple intra-articular involvement, with metaphyseal and/or epiphyseal comminution with reliable union rates , less revision procedures and reducing the tendency to place varus movement at the fracture site. The reduced bending movement of an intramedullary device has substantially reduced the fixation failure in osteoporotic bone. The anatomical alignment, stable internal fixation, rapid mobilization, and early functional rehabilitation of the knee are effective ways of managing distal femoral fractures, which can be achieved by Intramedullary nail. Another technique described by Liporace and Yoon for treatment of comminuted intra-articular fractures is the combination of nail and plate fixation.

The rationale of adding another locking plate is that fixation with a single lateral plate in complex distal femoral fractures could create an unstable environment that contributes to non-union or hardware failure. More rigid fixation like double plating provides better stability for a sufficient period of time to allow bone healing in distal femoral fractures with extensive metaphyseal comminution, fractures in osteoporotic bone, and in high energy.

The objective of this study is to compare the short term functional clinical and radiological outcomes of retrograde nail versus double plating for distal femoral extra-articular and simple articular fractures with metaphyseal comminution.