Abstract: A mobile bearing knee prosthesis enables a surgeon to convert a mobile bearing insert having articular surfaces, supported by a tibial base plate or tray from a rotating and translating prosthesis to one that rotates only. This conversion is accomplished with a fastener or locking member that connects through an opening in the insert to the tibial base plate. This prosthesis can be used as part of a total knee surgery when the surgeon chooses to use a prosthesis that incorporates a movable articular surface. In one embodiment, a projecting portion extends proximally from the insert and cooperates with a cam on the femoral component. The projecting portion can be a post extending up from the proximal surface of the insert and the femoral component includes an intercondylar surface that may contact the post to constrain the relative motion between the femoral component and the insert.

Abstract: A mobile bearing knee prosthesis enables a surgeon to convert a mobile bearing insert having articular surfaces, supported by a tibial base plate or tray from a rotating and translating prosthesis to one that rotates only. This conversion is accomplished with a fastener or locking member that connects through an opening in the insert to the tibial base plate. This prosthesis can be used as part of a total knee surgery when the surgeon chooses to use a prosthesis that incorporates a movable articular surface. In one embodiment, a projecting portion extends proximally from the insert and cooperates with a cam on the femoral component. The projecting portion can be a post extending up from the proximal surface of the insert and the femoral component includes an intercondylar surface that may contact the post to constrain the relative motion between the femoral component and the insert.

Abstract: A modular tibial trial prosthesis for attachment to a patient's surgically cut proximal tibia includes a tibial tray having proximal and distal surfaces, the distal surface to be fitted against the patient's surgically prepared proximal tibia during knee joint replacement surgery. The proximal surface of the tray accepts any one of a plurality of plastic liner inserts that fits the tray at the proximal tray surface with an interlocking connection. The liner inserts each have a distal surface for attachment to the tray and a proximal articulating surface that is receptive of a distal femoral articulating surface. The proximal articulating surface has concavely-shaped portions. The concavely-shaped portions of the liner inserts provide different articular geometries for selection by the user. A plurality of spacers of different thicknesses can be positioned in between a selected one of the plastic liner inserts and the tibial tray. Each spacer has proximal and distal surfaces.