EinleitungDie Anzahl an Endoprothesenimplantationen in Deutschland hat in den letzten Jahren deutlich zugenommen. Mittlerweile werden ca. 170 000 Knieprothesen in Deutschland implantiert und ca. 10 000 Wechseloperationen durchgeführt. Die Rate an periprothetischen Frakturen nach Knietotalendoprothesenimplantation beträgt 0,6-2,5%. Betroffen ist meist das distale Femur. In knapp 40 % der Fälle treten periprothetische Frakturen am Kniegelenk bei vor-
Periprosthetic Fractures around the KneeWith the increasing number of arthroplasties being performed, an elevated incidence of periprosthetic fractures around the knee can be observed. About 95 % of the fractures are located at the distal femur, 4 % are found at the tibia and 1% at the patella. The main risk factors to suffer from a periprosthetic fracture around the knee are high activity levels combined with an age lower than 60 years, revisionarthroplasty, long stems and osteoporosis. Femoral overstuffing, patella baja and lateral release are risk factors for patella fractures. At the femoral location, angle stable plates or a retrograde nail are the prefered implants. Cerclage wires enhance the biomechanical stability. Loose implants result in the necessity to perform a revision arthroplasty. According to the current literature, most periprosthetic fractures at the tibial side are accompanied with a loose implant, at the femoral side the implants are stably integrated in most cases. Periprosthetic patella fractures often have healing problems due to an impaired blood supply after an anteromedial arthrotomy. In general there is a high complication rate of 12 to 41 % in the treatment of periprosthetic fractures around the knee. This should be considered for the primary knee arthroplasty as well as in the treatment of the periprosthetic fractures.