Abstract: A modular femoral trial system is provided having femoral trial bases of various sizes and adapters which may be used to convert the base from a cruciate retaining trial to a cruciate sacrificing trial or a trial for an implant with increased built in stability.

Abstract: A patellar component is provided for fixation to a patella and a total knee arthroplasty surgical procedure in which multiple surfaces are provided on an outer ring on the inferior surface of the patellar component to provide multi-directional load bearing surfaces available to resist loosening of the patellar component and which requires minimal bone removal for implantation.

Abstract: A modular knee prosthesis includes a femoral component having a pair of spaced apart condylar portions each having a superior articulating surface and an inferior surface, and a boss structure disposed between and connecting the condylar portions. The prosthesis further includes an elongate stem member that mounts within the medullary canal of a distal portion of a femur, a collar and at least one securing bolt. The collar mounts upon the external end of the stem member, and has a distal surface that is substantially transverse to a longitudinal axis of the stem member when mounted thereon. The collar distal surface and the inferior surface of the boss structure define a selected mounting angle therebetween, and the securing bolt, which is adapted to mount within an aperture formed in the boss structure, has a head portion with a spherical first surface from which an elongate shaft portion extends.