Pyrolytic Carbon Implants With Porous Fixation Component And Methods Of Making The Same

1 . An orthopedic implant, comprising:

an articulation portion having a pyrolytic carbon bearing surface; and

a bone-fixation portion extending from the articulation portion and having a porous structure configured for bone on-growth or bone in-growth.

2 . The implant of claim 1 wherein the articulation portion further includes a substrate and the bone-fixation portion is bonded to the substrate.

3 . The implant of claim 2 further including a metal interlayer positioned at least partially between the bone-fixation portion and the substrate.

4 . The implant of claim 3 wherein the metal interlayer and the bone-fixation portion are comprised of the same metal material.

5 . The implant of claim 3 wherein the interlayer is comprised of a first metal and the bone fixation portion is comprised of a second metal, and the first metal is soluble with the second metal.

6 . The implant of claim 3 further including a metal outer layer at least partially covering the bone fixation portion and the interlayer, wherein the interlayer and metal outer layer bond the bone fixation portion to the substrate.

7 . The implant of claim 1 wherein the bone fixation portion is comprised of porous tantalum.

8 . The implant of claim 2 wherein the substrate is comprised of isotropic graphite.

9 . A method of forming an orthopedic implant, comprising:

providing a carbon member having an articulation portion and a bone fixation portion with a porous region;

applying a layer of pyrolytic carbon on an outer surface of the articulation portion;

applying a metal coating to the porous region of the bone fixation portion.

10 . The method of claim 9 in which the metal coating is selected from the group consisting of tantalum, titanium, niobium or alloys or combinations thereof.

11 . The method of claim 9 wherein the pyrolytic carbon is applied by chemical vapor deposition.

12 . A method of forming an orthopedic implant, comprising:

providing a substrate having a first surface and a second surface;

applying a layer of pyrolytic carbon to the first surface of the substrate;

placing an interlayer comprising a metal between the second surface of the substrate and a porous metal structure; and

bonding the porous metal structure and the substrate together to form the orthopedic implant.

13 . The method of claim 12 wherein the bonding comprises applying heat and pressure to the substrate, interlayer and porous metal structure for sufficient time to achieve solid-state diffusion between the interlayer and the porous metal structure.

14 . The method of claim 12 wherein one of the porous metal structure and the interlayer is comprised of tantalum and the other is comprised of titanium.

15 . The method of claim 12 wherein the interlayer is applied to the second surface of the substrate by chemical vapor deposition.

16 . The method of claim 12 wherein the pyrolytic carbon is applied by chemical vapor deposition.

17 . A method of forming an orthopedic implant, comprising:

applying a layer of pyrolytic carbon to a first surface of a substrate;

applying a metal interlayer to a second surface of the substrate;

contacting a porous metal structure with the metal interlayer; and

applying a second outer layer of metal to the substrate, interlayer and porous metal structure.

18 . The method of claim 17 in which the metal interlayer, metal outer layer and porous metal structure all comprise the same metal.

19 . The method of claim 18 in which the metal is selected from the group consisting of titanium, tantalum, niobium or alloys or combination of the same.

20 . The method of claim 17 in which the pyrolytic carbon is applied to the substrate by chemical vapor deposition.

21 . The method of claim 17 in which the metal interlayer is applied to the substrate by chemical vapor deposition.

22 . The method of claim 17 in which the metal outer layer is applied by chemical vapor deposition.

23 . A method of forming an orthopedic implant, comprising:

applying a layer of pyrolytic carbon to a first surface of a substrate;

applying an interlayer comprised of a metal to a second surface of the substrate;

providing a porous metal structure;

placing a metal foil between the interlayer and the porous metal structure; and

diffusion bonding the porous metal structure, the metal foil and the interlayer.