Identifying Non-Union Rates Using Carbo-fix Lateral Plate Devices and Standard Plate-Nail Construct in Distal Femur Fractures

Distal femur fractures are quite common, accounting for 3-6% of all femur fractures. In young adults, high energy trauma is most likely the cause, whereas in the elderly population, a low energy trauma due to osteoporosis is likely. Mortality for elderly patients with distal femur fractures is <20% at 1 year and approximately 50% at 5 years. Standard of care treatment for distal femur fractures is open reduction and internal fixation with locking plates, condylar screws, blade plates, or intramedullary nails, depending on the fracture characteristics. Non-union is a known complication of distal femur fixation; recent studies have shown non-union rates up to 33% with lateral locking plating. Patient factors and fracture patterns contribute significantly to the observed success of distal femur fixation operations.

A combined nail-plate fixation has increased in use in recent years, aiming to improve stability and allow early weightbearing. The nail-plate combination significantly increases the chances of the union and is generally used in non-union cases. Its use has flourished and is now an option for primary repair of distal femur fractures. Garala et al compared outcomes among fixation with a single lateral plate and a combined nail-plate construct and found 11 non-unions within the single lateral plate group compared to none in the nail-plate construct.

Metal plates and nails are commonly used for fixation. Carbon fiber, an emerging modality in orthopaedic surgery, has unique physical, chemical, and biological characteristics. It has a high strength to weight ratio and greater tensile strength compared to metallic materials, 7.5 times that of aluminum and 4 times that of steel. A retrospective study using carbon fiber lateral plates in supracondylar periprosthetic femur fractures in elderly patients reported all fractures resulting in union. When compared to titanium, carbon fiber had increased strength, stiffness, and lower wear resistance, as well as an elastic modulus half of bone. The Carbo-fix nails made of CF-PEEK have an advantage relative to metallic nails, although features are similar. These nails offer advantages related to imaging, as they are radiolucent on fluoroscopy and normal radiograph and decrease artifact on CT and MRI.

The purpose of this randomized clinical trial is to decrease non-union rates is distal femur fracture fixation. Carbo-fix lateral femur plate and standard intramedullary nail-plate constructs have been shown to have lower non-union rates. With decreased non-union rates, re-operation rates will decrease, leading to improved patient outcomes and clinical care. This study will be collecting data on the standard plate and nail combination and compare outcomes with the Carbofix plate to see differences in union rates. All procedures are currently standard of care and no procedures are research only.

Lateral plates and intramedullary nails are used as standard of care for distal femur fractures. Metal plates and nails are typically used, but the Carbofix carbon fiber version of the lateral locking plate can be used as standard of care as well. Non-union rates in the metal lateral locking plates are 20-33%, whereas the carbon fiber plates have a 3-9% non-union rate. The nail-plate combination has a 1-3% non-union rate. Using the Carbofix carbon fiber lateral plates and the standard nail-plate combination can reduce non-union rates in patients and provide better outcomes.