Abstract: The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises from about 5% by weight to 100% by weight of trans-1,2-difluorethylene (R1132(E)), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises an alkylated naphthalene and optionally but preferably an acid depleting moiety.

Abstract: A hybrid prosthetic femoral component has an outer bearing surface for engaging a tibial bearing and an inner surface for engaging a prepared distal femur. The inner surface having a distal surface, an anterior surface and a posterior surface, wherein said posterior surface has a first surface structure for allowing tissue ingrowth and the anterior and distal surfaces having a second surface structure for contacting bone cement. The first and second structure have different surface characteristics with different properties wherein the first surface structure is a porous surface and the second surface is a non-porous textured surface. The hybrid prosthetic femoral component further comprises an anterior chamfered surface and a posterior chamfered surface wherein the posterior chamfered surface includes the first surface structure and the anterior chamfered surface includes the second surface structure.

Abstract: An apparatus for guiding a surgical instrument for shaping the end of a bone includes an alignment plate which has a contact surface and is mounted with the contact surface in a plane substantially perpendicular to the physical axis of the bone and in contact with the bone. A cutting guide is mounted to the alignment plate for rotation about an axis which is substantially parallel to the mechanical axis. The cutting guide includes an instrument-receiver which maintains the surgical instrument in a cutting plane which is substantially parallel to the contact plane and at a predetermined distance from it.