Tibia component and knee-joint endoprosthesis system

A tibial component for a knee joint endoprosthesis, the tibial component comprising:

• a) a tibial plate with a top side and a bottom side;
• b) a shaft projecting from the bottom side for insertion into a medullary space of a tibia for anchoring the tibial component to the tibia;
• c) a positioning device for positioning the shaft on the tibial plate in different positions, wherein the positioning device comprises:
• a positioning element receptacle formed on the tibial plate, the positioning element receptacle having a wall with a first opening through which the shaft extends and a second opening opposite the first opening, and
• a positioning element arranged in the positioning element receptacle and operatively connected to the shaft,
• wherein the positioning element receptacle and the first opening are dimensioned such that the positioning element and the shaft are movable relative to the tibial plate in any direction parallel to a positioning plane that extends parallel to the top side;
• and
• d) a fixing device configured to be received in the second opening of the positioning element receptacle with the positioning element between the fixing device and the wall, the fixing device being movable from an alignment position, in which the positioning element and the shaft are movable relative to the tibial plate in parallel to the positioning plane, and an implantation position, in which the fixing device secures the positioning element and the shaft against movement relative to the tibial plate.