Abstract: A joint prosthesis is provided for replacing a joint between two bones in which one bone is normally permitted a substantial degree of rotary circumduction with respect to a second bone. A first member of the prosthesis is provided with a coupling portion enabling it to be attached to the elongated bone and includes a head having a generally saddle-shaped articulating surface facing away from the stem. The second member similarly has a connector adapted to connect the second member to the second bone, and has a head provided with a saddle-shaped articulating surface configured and sized to articulate with the saddle-shaped surface of the first member to enable one of the long bones to move in rotary circumduction with respect to the other. The saddle-shaped surfaces preferably are substantially congruent in shape.

Abstract: A joint prosthesis for replacing a joint between two elongated bones of the hand. A first member is provided with an elongated stem for reception in one of the elongated bones and includes a head remote from the stem, the head having a convex articulating surface and lateral articulating surfaces adjacent the convex surface and on each side thereof. A second member has a stem for reception in the other bone and a base remote from the stem, the base having a concave articulating surface and lateral articulating surfaces on each side thereof, the concave and lateral surfaces being adapted to engage and articulate with the respective convex and lateral articulating surfaces of the first member.

Abstract: An implantable knee joint prosthesis which comprises a tibial tray, an articulating tibial insert attached to the tibial tray, and a femoral condylar component adapted to cooperatively bear upon the tibial insert. The femoral component has an intercondylar recess having parallel lateral side walls and posterior and anterior bearing members defining the boundaries of the recess. The tibial insert includes an eminence extending superiorly into the intercondylar recess and dimensioned and shaped to provide defined stabilization limits for preventing posterior-anterior dislocation while allowing limited translation and essentially free rotation and angulation throughout most of the total range of articulation. Metal reinforcements serve to secure the insert to the tray.

Abstract: A bone implant prosthesis having an outer stress-free surface and a subsurface carried generally beneath and parallel to the outer surface for bearing tensile stresses. The prosthesis of the invention includes a plurality of slots undercutting the outer surface of the prosthesis thus forming a stress bearing subsurface to free the outer surface from being subjected to substantial stresses. The stress-free outer surface is readily adaptable to receive a porous coating to enhance bone ingrowth without decreasing the stress resistance characteristics of the prosthesis.

Abstract: A bone implant prosthesis having an outer stress-free surface and a subsurface carried generally beneath and parallel to the outer surface for bearing tensile stresses. The prosthesis of the invention includes a plurality of slots undercutting the outer surface of the prosthesis thus forming a stress bearing subsurface to free the outer surface from being subjected to substantial stresses. The stress-free outer surface is readily adaptable to receive a porous coating to enhance bone ingrowth without decreasing the stress resistance characteristics of the prosthesis.

Abstract: Cutting guide for a bone saw used to assure accurate bone cuts in implantation of prostheses and osteotomies. A cutting guide has a main body having guide elements that include a pair of guide surfaces that engage opposite sides of a saw blade. The guide surfaces guide the blade in a predetermined plane during the cutting process. In each pair of guide surfaces, the surfaces are spaced from one another along the plane a sufficient distance to enable the saw blade to pivot out of said plane away from engagement with at least one of the guide surfaces through an angle of at least 15.degree.. The cutting guide also includes means for attaching the guide to a bone surface to orient the guide elements with respect to the bone.