The invention relates to a joint prosthesis, especially a knee joint prosthesis, for establishing an articulated connection between a first bone and at least one second bone. The inventive prosthesis comprises a first component (1) that is at least indirectly linked with the first bone, at least one second component (2) on which the second bone at least indirectly supports itself and which is movably mounted on at least one bearing surface (22) of the first component (1), and a connecting element (4) that interlinks the first component (1) with the second component (2). The connecting element (4) comprises an elastically deformable element (5) that facilitates a deflection of the first component (1) relative to the second component (2) from an initial position. When the first component (1) is deflected, the elastically deformable element (5) generates a restoring force that acts upon the first component (1) and restores the first component (1) to the initial position.