The invention relates to equipment for inserting a joint prosthesis, in particular a femur component of a knee prosthesis. The equipment comprises a base frame (1) having a guiding plate (12) and a laterally protruding primary gage (11), a fastening device (99) on the bone, and a curved milling gage (7) having a main body (70) and a guiding piece (8), which can be moved along a curved guiding path (74) relative to the main body (70) and has a receptacle (87) for an abrasive tool (85). Furthermore, the equipment comprises an aligning device (17, 77), which places the curved milling gage (7) in a clearly defined relative position when the curved milling gage is inserted into the base frame (1). Due to the precise positioning in conjunction with the curved guiding path, the mounting seat can be prepared easily without damaging surrounding tissue. Thus, even large and complexly shaped prostheses, such as knee joint prostheses, can be reproducibly inserted in an easy and safe manner.
