ARTHROPLASTY SYSTEM AND RELATED METHODS

• US 20100049195A1
• Filed: 09/21/2009
• Published: 02/25/2010
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Otismed Corporation (Stryker Corporation)
• Inventors: Chi, Charlie W., Park, Ilwhan, Howell, Stephen M.
• Granted Patent: US 8,545,509 B2
• Time in Patent Office: Days
• US Class Current: 606/87
• CPC Class Codes: A61B 17/15 Guides therefor arrangements for guiding straight saw blades in general B23D51/025
• CPC Class Codes: A61B 17/155 Cutting femur
• CPC Class Codes: A61B 17/157 Cutting tibia
• CPC Class Codes: A61B 17/1703 using imaging means, e.g. by X-rays
• CPC Class Codes: A61B 17/1725 for applying transverse screws or pins through intramedullary nails or pins
• CPC Class Codes: A61B 17/1739 specially adapted for particular parts of the body
• CPC Class Codes: A61B 17/1742 for the hip
• CPC Class Codes: A61B 17/1764 for the knee
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• 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 2034/105 Modelling of the patient, e.g. for ligaments or bones
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/4504 Bones A61B5/4547 takes precedence
• CPC Class Codes: A61B 5/4514 Cartilage
• CPC Class Codes: A61B 5/4533 Ligaments
• CPC Class Codes: A61B 5/4585 Evaluating the knee
• CPC Class Codes: A61B 6/03 : Computed tomography [CT] echo-tomography A61B8/14
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing
• CPC Class Codes: G06T 2207/30008 : Bone
• CPC Class Codes: G06T 7/0012 : Biomedical image inspection
• CPC Class Codes: G06T 7/13 : Edge detection
• CPC Class Codes: G06T 7/30 : Determination of transform parameters for the alignment of images, i.e. image registration

Abstract

A method of manufacturing an arthroplasty jig is disclosed herein. The method may include the following: generate a bone model, wherein the bone model includes a three dimensional computer model of at least a portion of a joint surface of a bone of a patient joint to undergo an arthroplasty procedure; generate an implant model, wherein the implant model includes a three dimensional computer model of at least a portion of a joint surface of an arthroplasty implant to be used in the arthroplasty procedure; assess a characteristic associated with the patient joint; generate a modified joint surface of the implant model by modifying at least a portion of a joint surface of the implant model according to the characteristic; and shape match the modified joint surface of the implant model and a corresponding joint surface of the bone model.

Claims

1. A method of manufacturing an arthroplasty jig, the method comprising:

a). generate a bone model, wherein the bone model includes a three dimensional computer model of at least a portion of a joint surface of a bone of a patient joint to undergo an arthroplasty procedure;

b). generate an implant model, wherein the implant model includes a three dimensional computer model of at least a portion of a joint surface of an arthroplasty implant to be used in the arthroplasty procedure;

c.) assess a characteristic associated with the patient joint;

d.) generate a modified joint surface of the implant model by modifying at least a portion of a joint surface of the implant model according to the characteristic; and

e.) shape match the modified joint surface of the implant model and a corresponding joint surface of the bone model.

2. The method of claim 1, further comprising determining at least one of a location and orientation of a surgical cut plane relative to the implant model, wherein the surgical cut plane is associated with the implant model.

3. The method of claim 2, wherein the surgical cut plane corresponds to a distal resection to be made in the bone of the patient, wherein the bone is a femur.

4. The method of claim 2, wherein the surgical cut plane corresponds to a proximal resection to be made in the bone of the patient, wherein the bone is a tibia.

5. The method of claim 1, wherein the arthroplasty implant is at least one of a TKR or partial knee implant.

6. The method of claim 1, wherein the patient joint is at least one of an ankle, knee, hip, wrist, elbow, shoulder, vertebra-vertebra interface, vertebra-sacrum interface, and vertebra-skull interface.

7. The method of claim 1, wherein the bone is at least one of a femur and tibia.

8. The method of claim 1, wherein the joint surface of the bone includes a condyle articular surface.

9. The method of claim 8, wherein the joint surface of the arthroplasty implant includes a condyle articular surface.

10. The method of claim 1, wherein the bone model is representative of the at least a portion of the joint surface of the bone of the patient joint in a pre-deteriorated state.

11. The method of claim 1, wherein the characteristic includes a cartilage thickness of a generally non-deteriorated side of the patient joint.

12. The method of claim 11, wherein the modifying of the at least a portion of the joint surface of the implant model includes shifting the at least a portion of the joint surface of the implant model by the cartilage thickness.

13. The method of claim 12, wherein the shift is in a direction towards the interior of the implant model.

14. The method of claim 13, wherein the arthroplasty implant is a femur implant and the shift is at least one of anterior and proximal.

15. The method of claim 14, wherein the modified joint surface is associated with a posterior portion of an articular surface of a condyle of the femur implant, and the corresponding joint surface is associated with a posterior portion of an articular surface of a femur condyle of the bone model.

16. The method of claim 13, wherein the arthroplasty implant is a tibia implant and the shift is at least distal.

17. The method of claim 14, wherein the modified joint surface is associated with an articular surface of a condyle of the tibia implant, and the corresponding joint surface is associated with an articular surface of a tibia condyle of the bone model.

18. The method of claim 1, Wherein the characteristic includes a joint gap distance of a generally non-deteriorated side of the patient joint.

19. The method of claim 18, wherein the modifying of the at least a portion of the joint surface of the implant model includes shifting the at least a portion of the joint surface of the implant model by at least a portion of the joint gap distance.

20. The method of claim 19, wherein the at least a portion of the joint gap distance is approximately half of the joint gap distance.

21. The method of claim 19, wherein the joint gap distance is in a distal-proximal direction between opposed condylar articular surfaces of a femur and tibia.

22. The method of claim 19, wherein the shift is in a direction towards the interior of the implant model.

23. The method of claim 22, wherein the arthroplasty implant is a femur implant and the shift is at least one of anterior and proximal.

24. The method of claim 23, wherein the modified joint surface is associated with a posterior portion of an articular surface of a condyle of the femur implant, and the corresponding joint surface is associated with a posterior portion of an articular surface of a femur condyle of the bone model.

25. The method of claim 24, wherein the arthroplasty implant is a tibia implant and the shift is at least distal.

26. The method of claim 25, wherein the modified joint surface is associated with an articular surface of a condyle of the tibia implant, and the corresponding joint surface is associated with an articular surface of a tibia condyle of the bone model.

44. The method of claim 1, wherein the bone model is representative of the knee joint surface of a patient femur in a pre-degenerated state.

27. A method of manufacturing an arthroplasty jig, the method comprising:

a). generate a restored bone model, wherein the bone model includes a three dimensional computer model of at least a portion of a joint surface of a bone of a patient joint to undergo an arthroplasty procedure, wherein the restored bone model is representative of the bone in a pre-degenerated state;

b). generate an implant model, wherein the implant model includes a three dimensional computer model of at least a portion of a joint surface of an arthroplasty implant to be used in the arthroplasty procedure; and

c.) shape match an articular joint surface of the restored bone model and a corresponding articular joint surface of the implant model.

28. The method of claim 27, further comprising determining at least one of a location and orientation of a surgical cut plane relative to the implant model, wherein the surgical cut plane is associated with the implant model.

29. The method of claim 28, wherein the surgical cut plane corresponds to a proximal resection to be made in the bone of the patient, wherein the bone is a tibia.

30. The method of claim 27, wherein the arthroplasty implant is at least one of a TKR or partial knee implant.

31. The method of claim 27, wherein the patient joint is at least one of an ankle, knee, hip, wrist, elbow, shoulder, vertebra-vertebra interface, vertebra-sacrum interface, and vertebra-skull interface.

32. The method of claim 27, wherein the bone is at least one of a femur and tibia.

33. A method of manufacturing an arthroplasty jig, the method comprising:

a). generate a bone model, wherein the bone model includes a three dimensional computer model of at least a portion of a knee joint surface of a patient femur to undergo an arthroplasty procedure;

b.) identify at least one of a most distal point and a most posterior point of a condyle articular surface of the bone model;

c). generate an implant model, wherein the implant model includes a three dimensional computer model of at least a portion of a joint surface of a femoral arthroplasty knee implant to be used in the arthroplasty procedure;

d.) identify at least one of a most distal point and a most posterior point of a condyle articular surface of the implant model; and

e.) move at least one of the bone model and the implant model so the at least one of the most distal point and the most posterior point of the condyle articular surface of the bone model generally positionally correspond with the at least one of the most distal point and the most posterior point of the condyle articular surface of the implant model.

34. The method of claim 33, further comprising shape match the condyle articular surface of the bone model and the articular condyle surface of the implant model.

35. The method of claim 34, further comprising determining at least one of a location and orientation of a surgical cut plane relative to the implant model, wherein the surgical cut plane is associated with the implant model.

36. The method of claim 35, wherein the surgical cut plane corresponds to a distal resection to be made in the patient femur.

37. The method of claim 33, wherein identifying a most posterior point in step b includes defining an asymptotic line or plane along an anterior side of a femoral shaft of the bone model.

38. The method of claim 37, wherein identifying a most posterior point in step b further includes applying, in a tangential fashion to a posterior region of the articular condyle surface of the bone model, a line or plane generally parallel to a most proximal portion of the asymptotic line or plane.

39. The method of claim 33, wherein identifying a most distal point in step b includes defining an asymptotic line or plane along at least one of a medial side and a lateral side of a femoral shaft of the bone model.

41. The method of claim 33, wherein identifying a most distal point in step b includes defining a trochlear groove plane of the bone model and applying, in a tangential fashion to a distal region of the articular condyle surface of the bone model, a plane generally perpendicular to the trochlear groove plane.

42. The method of claim 33, wherein identifying a most posterior point in step b includes defining a trochlear groove plane of the bone model and applying, in a tangential fashion to a posterior region of the articular condyle surface of the bone model, a plane generally perpendicular to the trochlear groove plane.

43. The method of claim 33, wherein the arthroplasty implant is at least one of a TKR or partial knee implant.

40. The method of claim 40, wherein identifying a most distal point in step b further includes applying, in a tangential fashion to a distal region of the articular condyle surface of the bone model, a line or plane generally perpendicular to a most proximal portion of the asymptotic line or plane.

45. A method of manufacturing an arthroplasty jig, the method comprising:

a). generate two-dimensional images of a joint surface of a patient bone;

b). generate first data from the two-dimensional images, wherein the first data is representative of the joint surface in a deteriorated state;

c). generate second data from the two-dimensional images, wherein the second data is representative of the joint surface in a non-deteriorated state;

d). generate third data and fourth data positionally referenced to the third data, wherein the third data is representative of a joint surface of an arthroplasty implant and the fourth data is representative of a surgical cut plane associated with the arthroplasty implant;

e). generate fifth data from the first data, wherein the fifth data is representative of a surface of the arthroplasty jig that will matingly receive the joint surface;

f). generate sixth data by matching the second data and the third data, the resulting sixth data including a position of the fourth data when the second and third data are matched;

g). generate seventh data by merging the fifth data and the sixth data; and

h). employ the seventh data in manufacturing the arthroplasty jig from a jig blank.

46. The method of claim 45, wherein the two-dimensional images are at least one of MRI and CT.

47. The method of claim 45, wherein the first data includes a three-dimensional computer generated arthritic bone model.

48. The method of claim 45, wherein the first data includes a three-dimensional computer generate surface model.

49. The method of claim 45, wherein the second data includes a three-dimensional computer generated restored bone model.

50. The method of claim 45, wherein the second data includes a three-dimensional computer generated volume model.

51. The method of claim 45, wherein the third and fourth data are associated with a three-dimensional computer generated model of the arthroplasty implant.

52. The method of claim 45, wherein the second data includes a three-dimensional computer generated volume model, the third includes a joint surface of a three-dimensional computer generated model of the arthroplasty implant, and the sixth data is generated by surface matching a joint surface of the volume model and the joint surface of the model of the arthroplasty implant.

53. The method of claim 45, wherein the second data is positionally referenced to the first data and at least some of the data respectively resulting from the first and second data is similarly positionally referenced.

54. The method of claim 53, wherein the fifth and sixth data are positionally referenced to each other to facilitate their merging.

55. The method of claim 45, wherein the seventh data is used to generate automated manufacturing instructions employed by an automated manufacturing machine used to manufacture the arthroplasty jig from the jig blank.

56. The method of claim 55, wherein the automated manufacturing machine is at least one of a CNC machine and a SLA machine.

57. The method of claim 45, wherein the surgical cut plane corresponds to a distal resection to be made in the patient bone, wherein the patient bone is a femur.

58. The method of claim 45, wherein the surgical cut plane corresponds to a proximal resection to be made in the patient bone, wherein the patient bone is a tibia.

59. The method of claim 45, wherein the arthroplasty implant is at least one of a TKR or partial knee implant.

60. The method of claim 45, wherein the patient bone is at least one of a femur and tibia.

61. The method of claim 45, wherein the joint surface of the patient bone includes a condyle articular surface.

62. The method of claim 61, wherein the joint surface of the arthroplasty implant includes a condyle articular surface.

63. An arthroplasty jig for performing an arthroplasty procedure on a joint surface of a bone of a patient joint to receive an arthroplasty joint implant, the jig comprising:

a mating surface configured to matingly receive the joint surface;

a first saw guide oriented relative to the mating surface to result in a resection that allows the arthroplasty joint implant to restore the patient joint to a pre-degenerated alignment; and

a second saw guide oriented relative to the mating surface to result in a resection that allows the arthroplasty joint implant to cause the patient joint to have an alignment approaching a zero degree mechanical axis alignment.

64. The jig of claim 63, wherein approaching a zero degree mechanical axis means to be between approximately zero degrees mechanical axis and approximately three degrees from zero degrees mechanical axis.

65. The jig of claim 63, wherein the jig is at least one of a femur jig and a tibia jig.