Abstract: An improved prosthesis interface surface is incorporated on any implantable component where stable long lasting bone fixation is needed. The surface achieves immediate stabilization of the prosthetic component and promotes bony tissue ingrowth by either making the surface of a porous metal or ceramic or coating the surface of the interface surface with a porous metal or ceramic. In the preferred embodiment, the surface includes a large number of conical protrusions which are specifically designed to resist shear and torsional disruptive forces while accommodating the compression loads that occur during motion of a joint prosthesis. By utilizing a series of conical protrusions, the surface contact area of the interface surface is much greater than interface surfaces now in use and this large surface contact area improves stability and provides a large area for secure bony ingrowth fixation.

Abstract: An intramedullary reamer comprising a tapered cylindrical body member, a groove extending along the opposite sides and across the small end of the body member, a plurality of longitudinally disposed valleys disposed in advance of the groove to facilitate removal of cutting chips and a replaceable blade adapted to fit into the groove in the body member, the cutting edge of the blade being exposed above said groove, the open end of the blade being provided with locking means to secure the blade to the body member.