Minimally Invasive Plate Osteosynthesis for Periprosthetic Distal Femoral Fractures after Total Knee Arthroplasty

Purpose: To evaluate the outcomes of the treatment of distal femoral fractures using minimally invasive plate osteosynthesis following total knee arthroplasty (TKA). Materials and Methods: From July 2008 to October 2011, 14 patients were treated with minimally invasive plate osteosynthesis for periprosthetic fractures following TKA. The mean duration of follow-up was 19.2 months and the mean age was 69.7 years. Lewis and Rorabeck classification was used to categorize the type of fracture. Pre- and postoperative range of motion, femorotibial angle, and Knee society score, time to bony union, and complications were evaluated. Results: The mean range of motion was 108.4 degrees preoperatively and 107.3 degrees postoperatively. No significant difference was observed in the pre- and postoperative mean range of motion. The average time to bony union was 3.9 months. The knee society score was 82.6 points preoperatively and 78.9 points postoperatively. The mean femorotibial angle was changed from 6.1 degrees valgus postoperatively to 4.6 degrees valgus postoperatively. There was no complication during the follow-up. Conclusions: Minimally invasive plate fixation for distal femur fractures after TKA showed good results. Minimally invasive plate osteosynthesis is a recommendable treatment method for periprosthetic fractures.