[Roentgen diagnosis following knee surgery].

After ventralization of the tibial tuberosity (Bandi-operation) the elevation can be shown. Chip and cortical fractures radiologically are demonstrated. After medialization of the patella ligament (Roux-Hauser operation) the site of excision is seen as a hyperlucent area and the site of apposition as a hyperdense area. After implantation of a sledge prosthesis risk factors indicating future complications can be identified by early postoperative radiography.