Laser-produced porous surface

• US 10,398,559 B2
• Filed: 05/13/2014
• Issued: 09/03/2019
• Est. Priority Date: 12/06/2005
• Status: Active Grant

• Current Assignee: University of Liverpool
• Original Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Inventors: Jones, Eric, Sutcliffe, Christopher J., Stamp, Robin
• Primary Examiner(s): Mathew, Seema
• Application Number:
  US14/276,483
• Publication Number:
  US 20140249643A1
• Time in Patent Office: 1,939 Days
• CPC Class Codes: A61F 2/30 Joints
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30907 Nets or sleeves applied to surface of prostheses or in cement
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/3877 Patellae or trochleae
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30199 Three-dimensional shapes
• CPC Class Codes: A61F 2002/30243 the overall spherical surface being composed of a plurality of adjacent circular or polygonal segments, e.g. football-like shaped
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30915 made of a stack of bonded perforated sheets, grids or wire meshes
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30968 Sintering
• CPC Class Codes: A61F 2002/3097 : using laser
• CPC Class Codes: A61F 2002/30971 : Laminates, i.e. layered products
• CPC Class Codes: A61F 2002/3401 : with radial apertures, e.g. radial bores for receiving fixation screws
• CPC Class Codes: A61F 2002/3425 : the outer shell having non-meridian protrusions, e.g. fins or wings, located in planes inclined or perpendicular with respect to the equatorial plane
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0071 : spherical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2250/0023 : differing in porosity
• CPC Class Codes: A61L 27/306 : Other specific inorganic materials not covered by A61L27/303 - A61L27/32
• CPC Class Codes: A61L 27/56 : Porous materials, e.g. foams or sponges
• CPC Class Codes: B22F 10/28 : Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/32 : of the atmosphere, e.g. composition or pressure in a building chamber
• CPC Class Codes: B22F 10/36 : of energy beam parameters
• CPC Class Codes: B22F 10/366 : Scanning parameters, e.g. hatch distance or scanning strategy
• CPC Class Codes: B22F 10/38 : to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures
• CPC Class Codes: B22F 10/62 : by chemical means
• CPC Class Codes: B22F 10/64 : by thermal means control of energy beam parameters for post heating B22F10/364
• CPC Class Codes: B22F 12/41 : characterised by the type, e.g. laser or electron beam
• CPC Class Codes: B22F 2207/11 : Gradients other than composition gradients, e.g. size gradients
• CPC Class Codes: B22F 2999/00 : Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B22F 3/1109 : Inhomogenous pore distribution composite layers of porous nature B22F7/002
• CPC Class Codes: B22F 5/10 : of articles with cavities or holes, not otherwise provided for in the preceding subgroups
• CPC Class Codes: B23K 26/382 : by boring
• CPC Class Codes: B29C 2045/14327 : anchoring by forcing the material to pass through a hole in the article
• CPC Class Codes: B29C 37/0082 : Mechanical anchoring B29C66/303 takes precedence
• CPC Class Codes: B29C 45/14311 : using means for bonding the coating to the articles B29C45/14795 takes precedence
• CPC Class Codes: B29L 2031/7532 : Artificial members, protheses
• CPC Class Codes: B33Y 10/00 : Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 : Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing
• CPC Class Codes: C23C 24/10 : with intermediate formation of a liquid phase in the layer
• CPC Class Codes: C23C 26/02 : applying molten material to the substrate
• CPC Class Codes: C23C 4/02 : Pretreatment of the material to be coated, e.g. for coating on selected surface areas
• CPC Class Codes: C23C 4/18 : After-treatment
• CPC Class Codes: Y02P 10/25 : Process efficiency

Abstract

A method of forming an implant having a porous tissue ingrowth structure and a bearing support structure. The method includes depositing a first layer of a metal powder onto a substrate, scanning a laser beam over the powder so as to sinter the metal powder at predetermined locations, depositing at least one layer of the metal powder onto the first layer and repeating the scanning of the laser beam.

Claims

1. An orthopedic implant comprising:

a porous metallic first structure;

an intermediate structure; and

a porous metallic second structure, wherein said intermediate structure is located between and inseparable from said first and said second structures,

wherein a porosity of said intermediate structure is different than the porosities of either one or both of said first structure and said second structure, and

wherein said first structure has a pore size distribution in the range of 80 μ

m to 800 μ

m and said second structure has a pore size distribution greater than the pore size distribution of said first structure.

2. An orthopedic implant comprising:

a porous first structure defining a surface of the implant for directly contacting bone;

a porous second structure; and

an intermediate structure located between and inseparable from said first and said second structures, wherein said first structure has a thickness of less than approximately 2 mm, said intermediate structure has a thickness of less than approximately 5 mm, and said second structure has a thickness greater than approximately 0.5 mm.

3. The orthopedic implant according to claim 2, wherein the porous first structure and the porous second structure are metallic.

4. The orthopedic implant of claim 2, wherein the first structure is a bone ingrowth structure, and the second structure is a bearing support structure.

5. The orthopedic implant according to claim 4,

wherein either one or both of (i) said bone ingrowth structure includes a first portion having a first porosity and a second portion having a second porosity different than said first porosity and (ii) said bearing support structure includes a third portion having a third porosity and a fourth portion having a fourth porosity different than said third porosity.

6. The orthopedic implant according to claim 5, wherein said intermediate structure includes two barrier sections and a bridging section positioned between said two barrier sections, wherein said bridging section has a different porosity than said two barrier sections.

7. The orthopedic implant according to claim 5, wherein at least one of said bone ingrowth structure and said bearing support structure includes at least one lattice defined by unit cells.

8. The orthopedic implant according to claim 5, wherein said bone ingrowth structure has a graded porosity.

9. The orthopedic implant according to claim 5, wherein said bone ingrowth structure has a pore size distribution in the range of 80 μ

m to 800 μ

m and said bearing support structure has a pore size distribution greater than the pore size distribution of said bone ingrowth structure.

10. The orthopedic implant according to claim 5, further comprising:

a bearing surface formed from a polymer material, said bearing surface being interlocked with said bearing support structure,

wherein said intermediate structure inhibits said polymer material from translating through said bearing support structure and into said bone ingrowth structure.

11. The orthopedic implant according to claim 5, further comprising:

a bearing surface formed from a ceramic material, said bearing surface being attached to said bearing support structure.

12. The orthopedic implant according to claim 5, further comprising:

a polymeric liner including a plurality of grooves, wherein said polymeric liner is attached to the bearing support structure by bone cement that engages said grooves of said polymeric liner.

13. The orthopedic implant according to claim 5, wherein said orthopedic implant is an acetabular cup.

14. The orthopedic implant according to claim 5, wherein said orthopedic implant is a patella component.

15. The orthopedic implant according to claim 5, wherein said orthopedic implant is a baseplate of a tibial component.

16. The orthopedic implant according to claim 5, wherein said orthopedic implant is a glenoid component.

17. The orthopedic implant according to claim 5, wherein said orthopedic implant is a cartilage plug.

18. The orthopedic implant according to claim 5, wherein said bone ingrowth structure has a thickness of between 1 mm and 2 mm, said intermediate structure has a thickness of less than approximately 0.25 mm, said bearing structure has a thickness greater than approximately 0.5 mm.

19. The orthopedic implant according to claim 5, wherein said bone ingrowth structure has a thickness of less than 1.5 mm, said intermediate structure has a thickness of less than approximately 5 mm, said bearing structure has a thickness greater than approximately 0.5 mm.

20. The orthopedic implant of claim 2, wherein a porosity of said intermediate structure is different than porosities of either or both of said first and said second structures.

21. The orthopedic implant of claim 2, wherein said implant is integrally formed.

22. The orthopedic implant of claim 2, wherein either one or both of (i) said first structure includes a first portion having a first porosity and a second portion having a second porosity different than said first porosity and (ii) said second structure includes a third portion having a third porosity and a fourth portion having a fourth porosity different than said third porosity.

23. The orthopedic implant of claim 22, wherein said first structure includes said first and said second portions, and wherein said first and second portions of said first structure are along an axis passing through said first structure, said second structure, and said intermediate structure.

24. The orthopedic implant of claim 2, wherein a porosity of said intermediate structure is substantially less than a porosity of said first structure and a porosity of said third structure.

25. The orthopedic implant of claim 2, wherein a porosity of said first structure is different than a porosity of said second structure.

26. The orthopedic implant of claim 2, further comprising:

a surface made of polymer material attached to said second structure;

wherein said intermediate structure inhibits said polymer material from translating through said third structure to said first structure.

27. The orthopedic implant of claim 2, wherein either or both of said first and said second structures includes at least one lattice defined by unit cells.

28. The orthopedic implant of claim 2, wherein either or both of said first and said second structures includes at least one barb extending from an exterior surface thereof.

29. An orthopedic implant comprising:

a porous first structure;

a porous second structure; and

an intermediate structure located between and inseparable from said first and said second structures,

wherein said intermediate structure includes a first barrier section and a bridging section positioned directly adjacent to said first barrier section, said bridging section having a different porosity than said first barrier section, and

wherein the first and the second structures are made of the same material.

30. The orthopedic implant of claim 29, wherein said first structure is a bone ingrowth structure.

31. The orthopedic implant of claim 30, wherein said second structure is a bearing support structure.

32. The orthopedic implant of claim 29, wherein said implant is integrally formed.

33. An orthopedic implant comprising:

a porous first structure;

a porous second structure; and

an intermediate structure located between and inseparable from said first and said second structures, wherein said intermediate structure includes a first barrier section, a second barrier section, and a bridging section, said bridging section being positioned directly adjacent to said first barrier section, having a different porosity than said first and said section barrier sections, and being positioned between said first and said second barrier sections.