Method and apparatus for reducing rim loading of an acetabular shell

• US 20070106391A1
• Filed: 11/07/2005
• Published: 05/10/2007
• Est. Priority Date: 11/07/2005
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Ronk, Robert
• Granted Patent: US 8,002,842 B2
• Time in Patent Office: Days
• US Class Current: 623/22.210
• CPC Class Codes: A61B 17/1666 for the acetabulum
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61F 2/30724 Spacers for centering an implant in a bone cavity, e.g. in a cement-receiving cavity
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/3603 implanted without ablation of the whole natural femoral head endoprosthetic cartilage A61F2/30756
• CPC Class Codes: A61F 2/4609 of acetabular cups
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30354 Cylindrically-shaped protrusion and recess, e.g. cylinder of circular basis
• CPC Class Codes: A61F 2002/30355 Cylinder of elliptical or oval basis
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30685 Means for reducing or preventing the generation of wear particulates
• CPC Class Codes: A61F 2002/30726 : Centering or guiding rods, e.g. for insertion of femoral shafts
• CPC Class Codes: A61F 2002/30733 : Inserts placed into an endoprosthetic cavity, e.g. for modifying a material property
• CPC Class Codes: A61F 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/3079 : Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30805 : Recesses of comparatively large area with respect to their low depth
• CPC Class Codes: A61F 2002/3081 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30934 : Special articulating surfaces
• CPC Class Codes: A61F 2002/30939 : Means for modifying the geometry of articulating surfaces, e.g. for compensating excessive clearance caused by wear
• CPC Class Codes: A61F 2002/30967 : Diffusion bonding
• CPC Class Codes: A61F 2002/3401 : with radial apertures, e.g. radial bores for receiving fixation screws
• CPC Class Codes: A61F 2002/3403 : Polar aperture
• CPC Class Codes: A61F 2002/349 : Shell having a wavy or undulated peripheral rim
• CPC Class Codes: A61F 2002/465 : using heating means
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2220/0058 : soldered or brazed or welded
• CPC Class Codes: A61F 2230/0006 : circular
• CPC Class Codes: A61F 2230/0008 : elliptical or oval
• CPC Class Codes: A61F 2230/0019 : rectangular
• 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 2310/00167 : Diamond or diamond-like carbon
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/00395 : Coating or prosthesis-covering structure made of metals or of alloys
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61F 2310/0097 : Coating or prosthesis-covering structure made of pharmaceutical products, e.g. antibiotics
• CPC Class Codes: A61F 2310/00976 : Coating or prosthesis-covering structure made of proteins or of polypeptides, e.g. of bone morphogenic proteins BMP or of transforming growth factors TGF

Abstract

A prosthesis for replacing a portion of the anatomy including an outer bone engaging surface and an inner bearing surface. The prosthesis may include a rim disposed between the inner bearing surface and the outer bone engaging surface. The rim may include at least one contour operable to reduce loading on the rim.

Claims

1. A prosthesis for replacing a portion of the anatomy comprising:

an outer bone engaging surface;

an inner bearing surface; and

a rim disposed between the inner bearing surface and the outer bone engaging surface, the rim including at least one contour operable to reduce loading on the rim.

2. The prosthesis of claim 1, wherein the prosthesis is hemispherical and further comprises an apex.

3. The prosthesis of claim 2, wherein a coating is applied to the outer bone engaging surface of the body to assist in securing the body to the anatomy.

4. The prosthesis of claim 3, wherein the coating is selected from the group comprising porous metal matrix, porous plasma spray, calcium phosphate, hydroxyapatite, bone morphogenic protein, growth factor, peptide, antibiotic, or combinations thereof.

5. The prosthesis of claim 2, wherein the prosthesis further comprises at least one opening defined near the apex, the at least one opening operable to receive at least one biocompatible fastener to couple the outer bone engaging surface to the anatomy.

6. The prosthesis of claim 1, wherein the inner bearing surface defines at least one aperture for receipt of at least one bearing member.

7. The prosthesis of claim 6, wherein the at least one aperture is annular, and the at least one bearing member protrudes above the inner bearing surface.

8. The prosthesis of claim 7, wherein the at least one bearing member comprises an insert adapted to mate with the at least one aperture defined in the inner bearing surface;

and

wherein the insert is comprised of a material selected from the group comprising ceramic diamond compact, polycrystalline diamond compact or combinations thereof.

9. The prosthesis of claim 8, wherein the prosthesis is comprised of a bio-compatible metallic material, and the at least contour of the rim corresponds to the at least one bearing member to minimize a surface area of the inner bearing surface above the at least one bearing member.

10. The prosthesis of claim 9, wherein the at least one bearing member forms an articulated bearing surface for receipt of a femoral head.

11. A prosthesis for replacing a portion of the anatomy comprising:

a body defining an inner bearing surface, the inner bearing surface defining at least one recess;

at least one bearing member adapted to mate with the at least one recess;

wherein the body has a rim including at least one contour operable to reduce loading on the rim; and

wherein the at least one contour is positioned to correspond to the at least one bearing member.

12. The prosthesis of claim 11, wherein the body is hemispherical and further comprises an outer bone engaging surface and an apex.

13. The prosthesis of claim 12, wherein a coating is applied to the outer bone engaging surface of the body to assist in securing the body to the anatomy.

14. The prosthesis of claim 13, wherein the coating is selected from the group comprising porous metal matrix, porous plasma spray, calcium phosphate, hydroxyapatite, bone morphogenic protein, growth factor, peptide, antibiotic, or combinations thereof.

15. The prosthesis of claim 12, wherein the body further comprises at least one opening defined near the apex, the at least one opening operable to receive at least one biocompatible fastener to couple the body to the anatomy.

16. The prosthesis of claim 11, wherein the at least one aperture is annular, and the at least one bearing member protrudes above the inner bearing surface.

17. The prosthesis of claim 16, wherein the at least one bearing member is comprised of a material selected from the group comprising ceramic diamond compact, polycrystalline diamond compact or combinations thereof.

18. The prosthesis of claim 16, wherein the insert is press-fitted into the at least one recess.

19. The prosthesis of claim 17, wherein the body is comprised of a bio-compatible metallic material, and the at least one contour of the rim corresponds to the at least one bearing member to minimize a surface area of the inner bearing surface above the at least one bearing member.

20. The prosthesis of claim 19, wherein the body and at least one bearing member form an articulated bearing surface for receipt of a femoral head.

21. An acetabular prosthesis comprising:

an acetabular shell defining a plurality of recesses;

a plurality of bearing members configured to engage the plurality of recesses; and

wherein the acetabular shell includes a rim with a contoured surface which corresponds with the plurality of bearing members.

22. The acetabular prosthesis of claim 21, wherein the acetabular shell further comprises an outer bone engaging surface, and a coating is applied to the outer bone engaging surface to assist in securing the acetabular shell to the anatomy, the coating selected from the group comprising porous metal matrix, porous plasma spray, calcium phosphate, hydroxyapatite, bone morphogenic protein, growth factor, peptide, antibiotic, or combinations thereof.

23. The acetabular prosthesis of claim 21, wherein the acetabular shell further comprises at least one opening defined near the apex, the at least one opening operable to receive at least one biocompatible fastener to couple the acetabular shell to the anatomy.

24. The acetabular prosthesis of claim 21, wherein the plurality of recesses are annular, and the plurality of bearing members are annular, and the plurality of bearing members protrude above a surface of the acetabular shell when coupled to the plurality of recesses.

25. The acetabular prosthesis of claim 24, wherein the plurality of bearing members are comprised of a material selected from the group comprising ceramic diamond compact, polycrystalline diamond compact or combinations thereof.

26. The acetabular prosthesis of claim 25, wherein the acetabular shell is comprised of a bio-compatible metallic material, and the contoured surface of the rim corresponds to the plurality of bearing members to minimize a surface area of the acetabular shell above the plurality of bearing members.

27. A method for replacing a portion of the anatomy comprising:

preparing a surface of the anatomy;

providing a body having a first surface including at least one bearing member and a rim, the rim including at least one contour operable to reduce loading on the rim; and

interconnecting the body with the surface of the anatomy to form an articulated bearing surface.

28. The method of claim 27, further comprising:

reaming the surface of the anatomy;

spraying a coating on an exterior surface of the body, the coating selected from the group comprising porous metal matrix, porous plasma spray, calcium phosphate, hydroxyapatite, bone morphogenic protein, growth factor, peptide, antibiotic, or combinations thereof;

positioning the body over the surface of the anatomy; and

applying a force to the body to press-fit the body into the surface of the anatomy to couple the body to the anatomy.

29. The method of claim 27, further comprising:

reaming the surface of the anatomy;

drilling at least one hole in the surface of the anatomy;

providing at least one bio-compatible fastener;

providing at least one opening in the body for receipt of the at least one bio-compatible fastener; and

screwing the at least one bio-compatible fastener into the hole in the anatomy to secure the body to the anatomy.

30. The method of claim 27, further comprising:

providing at least one insert composed of a material selected from the group comprising ceramic diamond compact, polycrystalline diamond compact or combinations thereof;

forming at least one aperture in the first surface;

securing the at least one insert within the at least one aperture; and

wherein the at least one insert protrudes above the first surface to form the at least one bearing member on the body.

31. The method of claim 30, further comprising:

positioning the at least one insert over the at least one aperture;

applying a force to the at least one insert to press-fit the at least one insert to the first surface to secure the at least one insert to the first surface.

32. The method of claim 30, further comprising:

providing a femoral head;

coupling the femoral head to the body; and

wherein the femoral head contacts the at least one insert.

33. The method of claim 30, wherein the at least one contour of the rim is positioned to correspond to a location of the at least one insert on the first surface to minimize a surface area of the body above the insert.