Abstract: A knee prosthesis includes a tibial implant and a femoral implant. The tibial implant is pivotable with respect to the femoral implant about a substantially horizontal axis to permit a flexion/extension movement of the leg, and about a vertical axis which permits a limited pivoting of the tibia about the vertical axis. The vertical axis, about which the tibial implant pivots, is formed by a stud mounted so as to allow axial sliding, in a bore which serves as a rotational bearing therefor. Further, the vertical axis, about which the tibial implant pivots, is offset towards the front of the knee prosthesis with respect to the horizontal axis and is offset towards the inward side of the knee prosthesis with respect to a longitudinal axis of the tibial implant.