Ethnic-specific orthopaedic implants and custom cutting jigs

• US 9,078,755 B2
• Filed: 10/07/2011
• Issued: 07/14/2015
• Est. Priority Date: 02/25/2009
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Mahfouz, Mohamed Rashwan
• Primary Examiner(s): Johns, Andrew W
• Application Number:
  US13/268,262
• Publication Number:
  US 20120265496A1
• Time in Patent Office: 1,376 Days
• Field of Search: 382/128, 382/131, 382/132, 382/154, 606/88, 623/20.14, 623/20.21, 623/20.31
• US Class Current: 1/1
• CPC Class Codes: A61B 17/14 Surgical saws A61B17/1637 takes precedence; tooth saws A61C3/12 ; Accessories therefor
• CPC Class Codes: A61B 17/155 Cutting femur
• CPC Class Codes: A61B 17/1626 Control means; Display units
• CPC Class Codes: A61B 17/1675 for the knee
• CPC Class Codes: A61B 17/1764 for the knee
• CPC Class Codes: A61B 2017/568 produced with shape and dimensions specific for an individual patient
• CPC Class Codes: A61B 2034/104 Modelling the effect of the tool, e.g. the effect of an implanted prosthesis or for predicting the effect of ablation or burring
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2002/30952 using CAD-CAM techniques or NC-techniques
• CPC Class Codes: Y10T 29/49 Method of mechanical manufacture

Abstract

An orthopedic implant comprising: (a) a distal femoral component comprising a first condyle bearing surface having a first profile comprising at least three consecutive arcs of curvature; and (b) a proximal tibial component comprising a first condyle bearing surface having a second profile comprising at least three parallel arcs of curvature. The disclosure also includes a method of designing and fabricating an orthopedic implant, the method comprising: (a) evaluating images of distal femurs of a particular ethnicity to extract common shape features exhibited across an ethnicity that are unique to the ethnicity to create an ethnic specific template; (b) designing a distal femoral component comprising a first condyle surface using the ethnic specific template; and, (c) fabricating a distal femoral component embodying the first condyle surface.

Claims

1. A method of designing and fabricating an orthopedic implant, the method comprising:

evaluating images of distal femurs of a particular ethnicity to extract common shape features exhibited across an ethnicity that are unique to the ethnicity to create an ethnic specific template;

designing a distal femoral component comprising a first condyle surface using the ethnic specific template; and

,

fabricating a distal femoral component embodying the first condyle surface.

2. The method of claim 1, wherein evaluating the images of the distal femurs includes using principle component analysis to reduce dimensional variables and generate a global shape description.

3. The method of claim 1, further comprising comparing the images of the distal femurs of the particular ethnicity against a normalized distal femur model to identify shape differences between the images and model.

4. The method of claim 1, wherein the comparing step occurs independent of size differences between the images and model.

5. The method of claim 1, further comprising identifying common landmarks on the distal femurs and calculating at least one of linear measurements between landmarks on a particular distal femur, angular measurements between landmarks on a particular distal femur, and curvature of at least one condyle of a particular distal femur.

6. The method of claim 5, wherein the step of identifying common landmarks and calculating at least one of linear measurements between landmarks on a particular distal femur, angular measurements between landmarks on a particular distal femur, and curvature of at least one condyle of a particular distal femur, is done automatically by a software program.

7. The method of claim 1, wherein:

the step of designing the distal femoral component includes generating a curvature profile for the first condyle surface using the images of the distal femurs; and

,

the step of designing the distal femoral component includes generating a contour profile for the first condyle surface using the images of the distal femurs.

8. The method of claim 7, wherein the step of designing the distal femoral component includes parameterizing the contour profile with the curvature profile to design the first condyle surface.

9. The method of claim 1, further comprising the step of designing the distal femoral component comprising a second condyle surface using the ethnic specific template, wherein the step of fabricating the distal femoral component includes embodying the second condyle surface into the distal femoral component.

10. The method of claim 9, wherein:

the distal femoral component includes a medial condyle surface that comprises the first condyle surface; and

,

the distal femoral component includes a lateral condyle surface that comprises the second condyle surface.

11. The method of claim 10, wherein evaluating the images of the distal femur includes using principle component analysis to reduce dimensional variables and generate a global shape description.

12. The method of claim 10, further comprising comparing the images of the distal femur of the particular ethnicity against a normalized distal femur model to identify shape differences between the images and model.

13. The method of claim 12, wherein the comparing step occurs independent of size differences between the images and model.

14. The method of claim 10, further comprising identifying common landmarks on the distal femurs and calculating at least one of linear measurements between landmarks on a particular distal femur, angular measurements between landmarks on a particular distal femur, and curvature of at least one condyle of a particular distal femur.

15. The method of claim 14, wherein the step of identifying common landmarks and calculating at least one of linear measurements between landmarks on a particular distal femur, angular measurements between landmarks on a particular distal femur, and curvature of at least one condyle of a particular distal femur, is done automatically by a software program.

16. The method of claim 10, wherein:

the step of designing the distal femoral component includes generating a curvature profile for the first condyle surface using the images of the distal femurs;

the step of designing the distal femoral component includes generating a curvature profile for the second condyle surface using the images of the distal femurs;

the step of designing the distal femoral component includes generating a contour profile for the first condyle surface using the images of the distal femurs; and

,

the step of designing the distal femoral component includes generating a contour profile for the second condyle surface using the images of the distal femurs.

17. The method of claim 16, wherein:

the step of designing the distal femoral component includes parameterizing the contour profile with the curvature profile to design the first condyle surface; and

the step of designing the distal femoral component includes parameterizing the contour profile with the curvature profile to design the second condyle surface.

18. A method of designing and fabricating an orthopedic implant, the method comprising:

evaluating images of proximal tibias of a particular ethnicity to extract common shape features exhibited across an ethnicity that are unique to the ethnicity to create an ethnic specific template;

designing a proximal tibial component comprising a first condyle bearing surface using the ethnic specific template; and

,

fabricating a proximal tibial component embodying the first condyle bearing surface.

19. The method of claim 18, wherein evaluating the images of the proximal tibias includes using principle component analysis to reduce dimensional variables and generate a global shape description.

20. The method of claim 18, further comprising comparing the images of the proximal tibias of the particular ethnicity against a normalized proximal tibia model to identify shape differences between the images and model.

21. The method of claim 20, wherein the comparing step occurs independent of size differences between the images and model.

22. The method of claim 18, further comprising identifying common landmarks on the proximal tibias and calculating at least one of linear measurements between landmarks on a particular proximal tibia, angular measurements between landmarks on a particular proximal tibia, and curvature of at least one condyle receiver of a particular proximal tibia.

23. The method of claim 22, wherein the step of identifying common landmarks and calculating at least one of linear measurements between landmarks on a particular proximal tibia, angular measurements between landmarks on a particular proximal tibia, and curvature of at least one condyle receiver of a particular proximal tibia, is done automatically by a software program.

24. The method of claim 18, wherein:

the step of designing the proximal tibial component includes generating a curvature profile for the first bearing surface using the images of the proximal tibias; and

,

the step of designing the proximal tibial component includes generating a contour profile for the first bearing surface using the images of the proximal tibias.

25. The method of claim 24, wherein the step of designing the proximal tibial component includes parameterizing the contour profile with the curvature profile to design the first condyle bearing surface.

26. The method of claim 18, further comprising the step of designing the proximal tibial component comprising a second condyle bearing surface using the ethnic specific template, wherein the step of fabricating the proximal tibial component includes embodying the second condyle bearing surface into the proximal tibial component.

27. The method of claim 26, wherein:

the proximal tibial component includes a medial condyle bearing surface that comprises the first condyle bearing surface; and

,

the proximal tibial component includes a lateral condyle bearing surface that comprises the second condyle bearing surface.

28. The method of claim 27, wherein evaluating the images of the proximal tibias includes using principle component analysis to reduce dimensional variables and generate a global shape description.

29. The method of claim 27, further comprising comparing the images of the proximal tibias of the particular ethnicity against a normalized proximal tibia model to identify shape differences between the images and model.

30. The method of claim 29, wherein the comparing step occurs independent of size differences between the images and model.

31. The method of claim 27, further comprising identifying common landmarks on the proximal tibias and calculating at least one of linear measurements between landmarks on a particular proximal tibia, angular measurements between landmarks on a particular proximal tibia, and curvature of at least one condyle receiver of a particular proximal tibia.

32. The method of claim 31, wherein the step of identifying common landmarks and calculating at least one of linear measurements between landmarks on a particular proximal tibia, angular measurements between landmarks on a particular proximal tibia, and curvature of at least one condyle receiver of a particular proximal tibia, is done automatically by a software program.

33. The method of claim 27, wherein:

the step of designing the proximal tibial component includes generating a curvature profile for the first bearing surface using the images of the proximal tibias;

the step of designing the proximal tibial component includes generating a curvature profile for the second bearing surface using the images of the proximal tibias;

the step of designing the proximal tibial component includes generating a contour profile for the first bearing surface using the images of the proximal tibias; and

,

the step of designing the proximal tibial component includes generating a contour profile for the second bearing surface using the images of the proximate tibias.

34. The method of claim 33, wherein:

the step of designing the proximal tibial component includes parameterizing the contour profile with the curvature profile to design the first condyle bearing surface; and

the step of designing the proximal tibial component includes parameterizing the contour profile with the curvature profile to design the second condyle bearing surface.