Method of making orthopedic implants and the orthopedic implants

• US 7,603,192 B2
• Filed: 02/13/2007
• Issued: 10/13/2009
• Est. Priority Date: 02/13/2007
• Status: Expired due to Fees

• Current Assignee: OrthoHelix Surgical Designs, Inc. (Stryker Corporation)
• Original Assignee: OrthoHelix Surgical Designs, Inc. (Stryker Corporation)
• Inventors: Ducharme, Dustin, Martin, Amanda, Strnad, Lee A.
• Primary Examiner(s): Shechtman; Sean P
• Application Number:
  US11/706,616
• Publication Number:
  US 20080195240A1
• Time in Patent Office: 973 Days
• Field of Search: 700/97, 700/98, 700117-120, 700/182, 700/197, 700/206, 703/1, 703/6, 703/7, 703/11, 623/11.11, 623/16.11, 623/17.15, 623/22.34, 623 2235- 2237, 623/57, 623/901, 623/908, 623/914, 623/919, 623/925
• US Class Current: 700/98
• CPC Class Codes: A61B 17/8061 specially adapted for particular bones A61B17/70 and A61B17/74 take precedence
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders
• CPC Class Codes: Y10S 623/901 Method of manufacturing prosthetic device

Abstract

The present invention relates to a method of designing an orthopedic implant in which a plurality of samples of the bone are selected and a CT scan of each of the samples of the bone is taken so that the data from the CT scan can be used to generate a 3D graphical solid body model of each of the sample of the bone. The 3D graphical models are placed into a category of one or more of average, small, and large, and the center of mass and an X, Y and Z plane for each model is determined. The 3D graphical models for one category is assembled and aligned at the center of mass to create a categorized composite 3D graphical solid body model of the bone. The categorized composite 3D graphical model is sectioned at a specified interval to create a lofted contoured surface of a selected thickness which is cut to create a categorized implant profile. The categorized implant profile is graphically fit on the categorized composite 3D graphical model and on the 3D graphical model of each of the sample of the bone in a category to check for conformity to the surface of the bone. The categorized implant profile is used to create a design of the implant.

Claims

1. A method of making an orthopedic implant for a bone comprising the steps of

selecting a plurality of samples of the bone and taking a CT scan of each of the samples of the bone;

using the output from the CT scan to generate a 3D graphical solid body model of each of the samples of the bone;

placing the 3D graphical models into a category of one or more of a first category, a second category and a third category, determining the center of mass for each 3D graphical model, and generating an X, Y and Z plane for each model;

placing the 3D graphical models for one category into an assembly and aligning each of the 3D graphical models in that category at the center of mass to create a categorized composite 3D graphical solid body model of the bone;

forming a plurality of cross sections of the categorized composite 3D graphical model and building cross sections which are assembled to create a lofted contoured surface and cutting the lofted contoured surface to create a categorized implant form;

fitting the categorized implant form on the categorized composite 3D graphical model and on the 3D graphical model of each of the samples of the bone in a category to check for conformity to the surface of the bone;

using the categorized implant form to create a design of the implant; and

using the design of the implant to make the implant.

2. A method as set forth in claim 1 further including the step of creating a drawing of the categorized composite 3D graphical model for use to determine one or more of the size or the profile of the implant.

3. A method as set forth in claim 1 wherein the implant further includes fixation holes and the method further includes the step of using data of common fractures of the bone and of the need for fixation and reduction to determine the location and angles of the fixation holes in the implant.

4. A method as set forth in claim 2 wherein the method further includes the step of creating a physical model of the bone using the categorized composite 3D graphical model.

5. A method as set forth in claim 4 wherein the physical model of the bone comprises plastic and is created using a 3D plastic plotter.

6. A method as set forth in claim 5 wherein a physical model is created for each of the samples of the bone in each of the first size category, the second size category and the third size category.

7. A method as set forth in claim 6 wherein the method further includes the step of creating a physical model of the implant using the categorized implant form and wherein the physical model of the implant comprises plastic and is made using stereolithoaraphy.

8. A method as set forth in claim 7 wherein the physical model of the implant is fit on the physical model for each of the samples of the bone in the first size category, the second size category and the third size category.

9. A method as set forth in claim 8 further including the step of adjusting the design of the implant based on the results of the fit of the physical model of the implant on the physical model of one or more of the categorized composite 3D graphical solid body model of the bone or on the physical model of one of the samples of the bone in the first size category, the second size category and the third size category.

10. A method as set forth in claim 9 wherein the implant has a contour and the adjustment to the design includes a change in the contour of the implant.

11. A method as set forth in claim 9 wherein the implant has a profile and the adjustment to the design includes a change in the profile of the implant.

12. A method as set forth in claim 9 wherein the implant includes fixation holes and the adjustment to the design includes a change in the placement of the fixations holes.

13. A method as set forth in claim 9 wherein the implant includes fixation holes and the adjustment to the design includes a change in the angle of the fixations holes.

14. A method as set forth in claim 1 wherein the categorized composite 3D graphical solid model of the bone is used for a finite element analysis.

15. A method as set forth in claim 1 wherein the physical model of the bone is used for a finite element analysis.

16. A method as set forth in claim 14 wherein the categorized composite 3D graphical solid model of the bone is modified to simulate a fracture of the bone, and a categorized 3D graphical model of the implant is made and incorporated onto the categorized composite 3D graphical model of the bone to create a 3D graphical construct of a fractured bone with an implant and the 3D graphical construct is subjected to loads.

17. A method as set forth in claim 16 wherein the loads are applied in directions and magnitudes to simulate normal human activity and the stress and displacement of the implant is monitored to generate information for optimization of the implant.

18. A method as set forth in claim 17 wherein the information generated from the applied loads is used to optimize the design of the implant.

19. A method of making a plate for a one or more of a bone comprising the steps of

selecting a plurality of samples of the bone and taking a digital imaging scan of each of the samples of the bone and using the output from the digital imaging scan to generate a 3D graphical solid body model of each of the samples of the bone;

determining the center of mass for each 3D graphical model, and generating an X, Y and Z plane for each model relative to the center of mass and aligning each of the 3D graphical solid body models at the center of mass and in the X, Y, and Z planes to create a composite 3D graphical solid body model of the bone;

using the composite 3D graphical model to create a graphical bone plate profile;

graphically fitting the graphical bone plate profile on the composite 3D graphical model and on the 3D graphical model of each of the samples of the bone to check for conformity of the bone plate profile to the surface of the bone;

using the graphical bone plate profile to create a design of the bone plate; and

using the design of the bone plate to make a bone plate.

20. A method as set forth in claim 19 further including the step of sorting the 3D graphical solid body models into the categories of a first size having a first distal width, a second size having a second distal width and a third size having a third distal width, the first distal width being larger than the second distal width and small than the third distal width.

21. A method as set forth in claim 19 wherein the bone plate further includes fixation holes and the method further includes the step of using data of common fractures of the bone to determine the location and angles of the fixation holes in the bone plate.

22. A method as set forth in claim 21 wherein the method further includes the step of creating a physical model of the bone using the composite 3D graphical model.

23. A method as set forth in claim 22 wherein the physical model of the bone comprises resin, plastic or artificial bone.

24. A method as set forth in claim 19 wherein the method further includes the step of creating a prototype model of the bone plate using the bone plate profile.

25. A method as set forth in claim 19 wherein a physical model is created for each of the samples of the bone.

26. A method as set forth in claim 24 wherein the design of the bone plate is created in a right and a left version.

27. A method as set forth in claim 25 further including the step of creating a physical model of the bone plate using the graphical bone plate profile and wherein the physical model of the bone plate is fit on a plurality of physical models of the bone.

28. A method as set forth in claim 27 further including the step of making a design adjustment to the design of the bone plate based on the results of the fit of the physical model of the bone plate on the physical model of one or more of the composite 3D graphical solid body model of the bone or on the physical model of one of the samples of the bone.

29. A method as set forth in claim 28 wherein the design adjustment to the bone plate includes a change in the contour or the profile of the bone plate.

30. A method as set forth in claim 28 wherein the bone plate includes fixation holes which accept screws or pegs, and the adjustment to the design includes a change in the placement or the angle of the fixations holes.