Abstract: A prosthetic joint includes a first bearing element which is attached to a first bone and has a substantially flat bearing surface. A second element having a bearing surface is attached to a second bone. A bearing is disposed between the first and second elements. The bearing has a central axis and is defined by a first surface and a second surface. The first surface is substantially flat and is at least partially in contact with the first flat surface of the first element. At least a portion of the second surface is in contact with the surface of the second element. The area of the planform of the first surface of the bearing is smaller than, and dissimilar in shape from, the area of the planform defined by the second surface of the bearing.