[Periprosthetic fractures of the knee joint]

Periprosthetic fractures are a challenging problem in view of the demographic development and the increasing number of implanted prostheses. Most of these fractures occur postoperatively after a period of two to four years after implantation of a total knee arthroplasty. They are usually caused by traumata, implantation-specific factors and loosening of the prosthesis. Beside further risk factors osteopenia and a reduced mobility of the prosthesis predispose to these fractures. Numerous classifications which also include a loosening of the prosthesis in the fracture discription are an important tool for planning the therapy. Beside the conservative treatment, the stabilization of the fracture or changing the prosthesis should be considered. The treatment options of periprosthetic fractures of the knee joint are discussed in view of different initial situations with the aim of achieving a load-stable situation.