Knee prosthesis

Claim 2

A knee prosthesis for implanting with cement in a human knee comprising: (a) a single curved elongated body portion having upper and lower surfaces, and having posterior and anterior ends; (b) single post means fixedly attached to said curved body portion intermediate said posterior and anterior ends and extending generally upwardly from said upper surface for interaction with the cement with which used to resist in and of itself all twisting forces which might be encountered in the use of the prosthesis and to resist tension and compression forces, said post means in cross section along a substantial portion of the length thereof is cross shaped and said post means is of a reduced size in cross-sectional area at a midportion halfway between the upper and lower ends thereof, and with said post means increasing in cross-sectional size from said midportion towards said upper and lower ends; and (c) at least one cement holding means of less height than said post, fixedly attached to said body portion and extending in a direction generally remote from said lower surface for interaction with the cement with which used to provide support to said body portion and to resist tension and compression forces along a substantial portion of the length of said body portion.

Claim 3

A knee prosthesis for implanting with cement in a human knee, comprising: (a) a curved elongated body portion having upper and lower surfaces, and having posterior and anterior ends; (b) a post fixedly attached to said curved body portion intermediate said posterior and anterior ends and extending generally upwardly from said upper surface, said post in cross section along a substantial portion of the length being cross-shaped for preventing rotation of said curved body portion during use when implanted in a knee with cement; (c) a plurality of cement holding rings fixedly attached to said body portion, said rings extending generally upwardly from said upper surface, said rings being disposed in spaced relationship with one another and said post, and being disposed along the length of said body portion intermediate said posterior and anterior ends, each of said rings extending forwardly and rearwardly towards the anterior and posterior ends of said body portion and including forward and rearward junctures with said body portion, each of said rings including fillets respectively at said forward and rearward junctures, each of said rings including an enlarged ringlike means and a reduced portion smaller than said enlarged ringlike means connecting said enlarged ringlike means with said body portion for anchoring against tension forces said body portion to a knee in which implanted with cement and for resisting compression forces on said body portion.

Claim 4

A knee prosthesis for implanting with cement in a human knee, comprising: (a) a curved elongated body portion having upper and lower surfaces, and having posterior and anterior ends; (b) a post fixedly attached to said curved body portion intermediate said posterior and anterior ends and extending generally upwardly from said upper surface, said post in cross section along a substantial portion of the length being cross-shaped for preventing rotation of said curved body portion during use when implanted in a knee with cement; (c) a plurality of cement holding rings fixedly attached to said body portion, said rings extending generally upwardly from said upper surface, said rings being disposed in spaced relationship with one another and said post, and being disposed along the length of said body portion intermediate said posterior and anterior ends, each of said rings extending forwardly and rearwardly towards the anterior and posterior ends of said body portion and including forward and rearward junctures with said body portion, each of said rings including fillets respectively at said forward and rearward junctures, each of said rings including an enlarged ringlike means and a reduced portion smaller than said enlarged ringlike means connecting said enlarged ringlike means with said body portion for anchoring against tension forces said body portion to a knee in which implanted with cement and for resisting compression forces on said body portion.