A joint prosthesis, for example, a knee joint or shoulder joint prosthesis, comprising a first, socket-holding prosthesis part for attachment to a first bone and a second, ball-holding prosthesis part for attachment to a second bone that intermates with the first prosthesis part, wherein the first bone and the second bone are situated at either side of a joint, and wherein the ball of the second prosthesis part is rotatably received in the socket of the first prosthesis part, wherein the first prosthesis part can be coupled with the first bone by applying tensile strain bearing rods, and wherein when the mounted prosthesis is in a virtually unloaded condition there is no significant tensile force in the rods.