Prosthetic joint with diamond coated interfaces

• US 6,010,533 A
• Filed: 04/18/1997
• Issued: 01/04/2000
• Est. Priority Date: 08/12/1994
• Status: Expired due to Term

• Current Assignee: Diamicron, Inc.
• Original Assignee: Diamicron, Inc.
• Inventors: Garrick, Richard M., Pope, Bill J.
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US08/844,395
• Time in Patent Office: 991 Days
• Field of Search: 359/642, 156/613, 156/614, 428/336, 623/16, 623/18, 623/20, 623/22, 623/66
• US Class Current: 623/22.15
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/3676 Distal or diaphyseal parts of shafts
• CPC Class Codes: A61F 2002/30836 knurled
• CPC Class Codes: A61F 2002/3085 with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30934 Special articulating surfaces
• CPC Class Codes: A61F 2002/30968 Sintering
• CPC Class Codes: A61F 2002/3611 Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/3631 with an integral complete or partial peripheral collar or bearing shoulder at its base
• CPC Class Codes: A61F 2002/4631 the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/0058 Coating made of diamond or of diamond-like carbon DLC
• CPC Class Codes: A61L 27/303 Carbon
• CPC Class Codes: A61L 27/306 Other specific inorganic materials not covered by A61L27/303 - A61L27/32

Abstract

A prosthetic joint with polycrystalline diamond compact coated interfaces and a method for making the same are disclosed. The prosthetic joint has a diamond layer formed on at least one of the interacting, load-bearing surfaces of the joint. The diamond layer adds resistance to damage from impacts and, when polished, gives the joint a low coefficient of friction, thereby increasing the life of the joint. In accordance with one aspect of the invention, the diamond layer is formed of polycrystalline diamond compact having a common diamond particle diameter of less than 1 micron to further reduce friction.

Claims

1. A method of making a prosthetic joint having load-bearing surfaces which interact to enable rotation of one of the load-bearing surfaces relative to the other, the method comprising the steps of:

(a) coating at least one of the load-bearing surfaces with a polycrystalline diamond compact; and

(b) bonding the compact to said diamond-coated load-bearing surface to form a diamond layer over said diamond-coated load-bearing surface;

wherein step (b) comprises bonding a compact to a first of the load-bearing surfaces by using one of the group of processes consisting of a sintering process under high pressure and high temperature, a high temperature laser, chemical vapor deposition, electroplating and forming a matrix of high molecular weight polyethylene.

2. The method of claim 1, wherein step (a) comprises coating both load-bearing surfaces with a polycrystalline diamond compact to form a pair of diamond layers, each over a respective one of the load-bearing surfaces.

3. The method of claim 1, wherein step (a) comprises coating at least one of the load-bearing surfaces with a polycrystalline diamond compact having diamond particles with a common diameter of less than 100 microns.

4. The method of claim 1, wherein step (a) comprises coating at least one of the load-bearing surfaces with a polycrystalline diamond compact having diamond particles with a common diameter of less than 1 micron.

5. The method of claim 1, wherein step (a) comprises coating at least one of the load-bearing surfaces with a polycrystalline diamond compact having diamond particles with a common diameter of between about 1 nanometer and 1 micron.

6. The method of claim 1, further comprising the step of polishing the diamond layer to a high luster to thereby provide the diamond layer a low coefficient of friction.

7. The method of claim 6, wherein said polishing step comprises polishing the diamond layer to an Ra value of between 0.1 and 0.010 microns.