The Outcome and Complications of the Locked Plating Management for the Periprosthetic Distal Femur Fractures after a Total Knee Arthroplasty

The periprosthetic fractures around the knee are becoming more common with the ever-increasing incidence of the total knee replacements.1) Most of the fractures are the low-velocity fractures, which occur as a result of a combination of the torsional and axial loads.2) Osteoporosis, local osteolysis, inflammatory arthritis and the revision knee arthroplasty may serve as the additional risk factors.3,4) Distal Background: The osteosynthesis of the periprosthetic fractures following a total knee arthroplasty (TKA) can be technically difficult with the relatively small satisfactory outcomes and the high complication rates.The purpose of the study is to analyze the mid-term radiological and functional outcomes following the locked plating of the distal femur periprosthetic fractures after a TKA.Methods: Records of 20 patients with a periprosthetic distal femur fracture following TKA treated by the locked plate osteosynthesis were retrospectively evaluated.The union rate, complications and functional outcome measures were analyzed.Results: Successful union was achieved in 18 of the 19 patients available for the follow-up.The mean follow-up was 39 ± 10 months.Significant reductions (p < 0.05) in the range of motion and Western Ontario and McMaster Universities Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were evident in the follow-up.Secondary procedures were required in 5 patients to address the delay in union and the reduced knee range of motion.The osteosynthesis failed in 1 patient who underwent a revision TKA.Conclusions: The satisfactory union rates can be achieved with the locked plate osteosynthesis in the periprosthetic distal femur fractures after TKA.Prolonged rehabilitation coupled with the un-modifiable risk factors can decrease the activity and satisfaction levels, which can significantly alter the functional outcome.