COMPLIANT ANTI-RESORPTION IMPLANT

• US 20150032218A1
• Filed: 01/07/2013
• Published: 01/29/2015
• Est. Priority Date: 01/18/2012
• Status: Active Grant

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Inventors: Landon, Ryan L.
• Granted Patent: US 10,226,347 B2
• Time in Patent Office: Days
• US Class Current: 623/20.35
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2002/30006 differing in density or specific weight
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/3082 Grooves
• CPC Class Codes: A61F 2002/30879 Ribs
• CPC Class Codes: A61F 2002/30971 Laminates, i.e. layered products
• CPC Class Codes: A61F 2002/30985 using three dimensional printing [3DP]

Abstract

Systems, devices, and methods are described for providing orthopedic implants that reduces the negative effects of stress shielding on surrounding bone structure. The orthopedic implants are comprised of two portions, a shell portion that forms an articulation interfaces and an intermediate portion that forms a bone interface. The shell portion is designed to reduce absorption of Carticulation forces and evenly distribute incident forces to the intermediate portion. The intermediate portion is designed to form a strong interface with native bone and transmit forces from the shell into the bone.

Claims

1. An orthopedic implant comprising:

a shell region having an outer articulation surface; and

an intermediate region having a bone interface, said intermediate region having different mechanical properties than the shell region.

2. The orthopedic implant of claim 1, wherein the cross-sectional area of the shell region is substantially uniform.

3. The orthopedic implant of claim 2, wherein the thickness of the shell region is varied.

4. The orthopedic implant of claim 1, wherein the thickness of the shell region is substantially uniform.

5. The orthopedic implant of claim 1, wherein the intermediate region exhibits a different modulus of elasticity than the shell region.

6. The orthopedic implant of claim 1, wherein the intermediate region has a different density than the shell region.

7. The orthopedic implant of claim 1, wherein the intermediate region has a different porosity than the shell region.

8. The orthopedic implant of claim 1, wherein the intermediate region is comprised of a different material than the shell region.

9. The orthopedic implant of claim 1, wherein the intermediate region is movable relative to the shell region.

10. The orthopedic implant of claim 1, wherein the bone interface comprises a porous bone ingrowth surface.

11. The orthopedic implant of claim 1, wherein contours of the bone interface are different than an inner contour of the shell.

12. The orthopedic implant of claim 1, wherein the bone interface is shaped to accommodate a standard resected bone geometry.

13. The orthopedic implant of claim 1, wherein an interior surface of the shell region has a substantially smooth contour, and the intermediate region has a shell interface that matches the contour of the interior surface.

14. The orthopedic implant of claim 1, wherein the shell region further comprises strengthening ribs.

15. The orthopedic implant of claim 14, wherein the ribs are disposed at an anterior portion of the shell region.

16. The orthopedic implant of claim 14, wherein the ribs are disposed on condylar portions of the shell region.

17. The orthopedic implant of claim 14, wherein the ribs are disposed at a junction between condylar portions of the shell region.

18. The orthopedic implant of claim 14, wherein the ribs are disposed in an internal portion of the shell region.

19. A method of manufacturing an orthopedic implant, comprising:

forming a shell region of the orthopedic implant; and

forming an intermediate region of the orthopedic implant, wherein the intermediate region has different mechanical properties than the shell region.

20. The method of claim 19, wherein the shell region and intermediate region are formed by rapid manufacturing.

21. The method of claim 19, wherein the shell region is formed using a different material than the intermediate region.

22. The method of claim 19, wherein the intermediate region is formed by depositing material at a different density than the shell region.

23. The method of claim 19, wherein the intermediate region is formed as a porous region, and the shell region is formed as a solid region.