Preoperatively planning an arthroplasty procedure and generating a corresponding patient specific arthroplasty resection guide

• US 8,617,171 B2
• Filed: 04/13/2011
• Issued: 12/31/2013
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Otismed Corporation (Stryker Corporation)
• Inventors: Park, Ilwhan, Song, Keun, Mishin, Oleg, Santarella, Michael
• Primary Examiner(s): BATES, DAVID W
• Application Number:
  US13/086,275
• Publication Number:
  US 20110214279A1
• Time in Patent Office: 993 Days
• Field of Search: 606/88, 606/87, 703/7
• US Class Current: 606/88
• CPC Class Codes: A61B 17/122 Clamps or clips , e.g. for the umbilical cord for the vas deferens A61F6/206
• CPC Class Codes: A61B 17/1675 for the knee
• CPC Class Codes: A61B 17/1764 for the knee
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/105 Modelling of the patient, e.g. for ligaments or bones
• 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 6/505 for diagnosis of bone
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2002/4633 for selection of endoprosthetic joints or for pre-operative planning
• CPC Class Codes: A61F 2002/4658 for measuring dimensions, e.g. length
• CPC Class Codes: A61F 2002/4668 for measuring angles
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G06F 18/22 Matching criteria, e.g. proximity measures
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics
• CPC Class Codes: G06T 19/20 Editing of 3D images, e.g. changing shapes or colours, aligning objects or positioning parts
• CPC Class Codes: G06T 2207/10004 Still image; Photographic image
• CPC Class Codes: G06T 2207/10088 : Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/20221 : Image fusion; Image merging
• CPC Class Codes: G06T 2207/30008 : Bone
• CPC Class Codes: G06T 2207/30052 : Implant; Prosthesis
• CPC Class Codes: G06T 2210/41 : Medical
• CPC Class Codes: G06T 2219/008 : Cut plane or projection plane definition
• CPC Class Codes: G06T 2219/2004 : Aligning objects, relative positioning of parts
• CPC Class Codes: G06T 5/50 : using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/0012 : Biomedical image inspection
• CPC Class Codes: G06T 7/33 : using feature-based methods
• CPC Class Codes: G06V 10/751 : Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching
• CPC Class Codes: G06V 2201/03 : Recognition of patterns in medical or anatomical images
• CPC Class Codes: G06V 2201/033 : of skeletal patterns
• CPC Class Codes: Y10T 29/49 : Method of mechanical manufacture

Abstract

Methods of manufacturing a custom arthroplasty resection guide or jig are disclosed herein. For example, one method may include: generating MRI knee coil two dimensional images, wherein the knee coil images include a knee region of a patient; generating MRI body coil two dimensional images, wherein the body coil images include a hip region of the patient, the knee region of the patient and an ankle region of the patient; in the knee coil images, identifying first locations of knee landmarks; in the body coil images, identifying second locations of the knee landmarks; run a transformation with the first and second locations, causing the knee coil images and body coil images to generally correspond with each other with respect to location and orientation.

Claims

1. A method of manufacturing a custom arthroplasty resection guide, the method comprising:

generate a three dimensional femur bone computer model from MRI knee coil two dimensional images, wherein the MRI knee coil two dimensional images include a knee region of a patient;

locate positions of an approximate hip center and an approximate femur knee center in coronal view MRI body coil two dimensional images, wherein the positions are relative to at least two axes in a global coordinate system of a computer environment and wherein the MRI body coil two dimensional images include a hip region of the patient and the knee region of the patient;

cause the three dimensional femur bone computer model and approximate hip center and approximate femur knee center to generally correspond with each other with respect to location and orientation in the global coordinate system of the computer environment by aligning first locations of knee landmarks in the MRI knee coil two dimensional images and second locations of the knee landmarks in the MRI body coil two dimensional images;

define across the three dimensional femur bone computer model a femoral mechanical axis between the approximate femur knee center and the approximate hip center;

locate a most distal condylar point of the three dimensional femur bone computer model;

define a distal plane that is orthogonal to the femoral mechanical axis in a coronal view of the three dimensional femur bone computer model, wherein the distal plane also passes through the most distal condylar point;

define a resection plane that is parallel to the distal plane and proximally offset a distance along the femoral mechanical axis from the distal plane; and

manufacture the custom arthroplasty resection guide by using data associated with the resection plane to define a resection guide in the custom arthroplasty resection guide.

2. The method of claim 1, wherein the three dimensional femur bone computer model includes at least one of a femur bone only computer model or a femur arthritic computer model representing bone and cartilage.

3. The method of claim 1, wherein the distance of proximal offset between the distal plane and the resection plane is based on a dimension of a candidate femoral implant.

4. The method of claim 1, wherein in causing the three dimensional femur bone computer model and approximate hip center and approximate femur knee center to generally correspond with each other with respect to location and orientation in the global coordinate system of the computer environment, the method further includes:

identifying the first locations of the knee landmarks in the MRI knee coil two dimensional images;

identifying the second locations of the knee landmarks in the MRI body coil two dimensional images; and

causing a computer processor to run a transformation with the first and second locations, causing the MRI knee coil two dimensional images and MRI body coil two dimensional images to generally correspond with each other with respect to location and orientation in the global coordinate system.

5. The method of claim 4, wherein the transformation employs an Iterative Closest Point algorithm or gradient descent optimization.

6. The method of claim 4, wherein the transformation causes the MRI knee coil two dimensional images to reposition in the global coordinate system to the location and orientation of the MRI body coil two dimensional images.

7. The method of claim 1, wherein the approximate femur knee center is close to a medial-lateral center of a distal femur intercondylar groove, and the approximate hip center is at a center of a femur head.

14. The method as in any of claim 1 or 8, in which computer processing is employed in aligning the first locations of the knee landmarks in the MRI knee coil two dimensional images and the second locations of the knee landmarks in the MRI body coil two dimensional images.

15. The method as in any of claim 1 or 8, in which an image spacing of the MRI body coil two dimensional images is different from an image spacing of the MRI knee coil two dimensional images.

8. A method of manufacturing a custom arthroplasty resection guide, the method comprising:

generate a three dimensional tibia bone computer model from MRI knee coil two dimensional images, wherein the MRI knee coil two dimensional images include a knee region of a patient;

locate positions of an approximate ankle center and an approximate tibia knee center in coronal view MRI body coil two dimensional images, wherein the positions are relative to at least two axes in a global coordinate system of a computer environment and wherein the MRI body coil two dimensional images include an ankle region of the patient and the knee region of the patient;

cause the three dimensional tibia bone computer model and approximate ankle center and approximate tibia knee center to generally correspond with each other with respect to location and orientation in the global coordinate system of the computer environment by aligning first locations of knee landmarks in the MRI knee coil two dimensional images and second locations of the knee landmarks in the MRI body coil two dimensional images;

define across the three dimensional tibia bone computer model a tibial mechanical axis between the approximate tibia knee center and the approximate ankle center;

locate a condylar point of the three dimensional tibia bone computer model;

define a proximal plane that is orthogonal to the tibial mechanical axis in a coronal view of the three dimensional tibia bone computer model, wherein the proximal plane also passes through a condylar point;

define a resection plane that is parallel to the proximal plane and distally offset a distance along the tibial mechanical axis from the proximal plane; and

manufacture the custom arthroplasty resection guide by using data associated with the resection plane to define a resection guide in the custom arthroplasty resection guide.

9. The method of claim 8, wherein the three dimensional tibia bone computer model includes at least one of a tibia bone only computer model or a tibia arthritic computer model representing bone and cartilage.

10. The method of claim 8, wherein the distance of distal offset between the proximal plane and the resection plane is based on a dimension of a candidate tibial implant.

11. The method of claim 8, wherein in causing the three dimensional tibia bone computer model and approximate ankle center and approximate tibia knee center to generally correspond with each other with respect to location and orientation in the global coordinate system of the computer environment, the method further includes:

identifying the first locations of the knee landmarks in the MRI knee coil two dimensional images;

identifying the second locations of the knee landmarks in the MRI body coil two dimensional images; and

causing a computer processor to run a transformation with the first and second locations, causing the MRI knee coil two dimensional images and MRI body coil two dimensional images to generally correspond with each other with respect to location and orientation in the global coordinate system.

12. The method of claim 11, wherein the transformation employs an Iterative Closest Point algorithm or gradient descent optimization.

13. The method of claim 11, wherein the transformation causes the MRI knee coil two dimensional images to reposition in the global coordinate system to the location and orientation of the MRI body coil two dimensional images.

16. The method of claim 8, wherein the approximate tibia knee center is close to a medial-lateral center of a proximal tibia spine, and the approximate ankle center is close to a cortical bone rim of an ankle plafond.

17. A method of manufacturing a custom arthroplasty resection guide, the method comprising:

a) locate coordinate system points in a computer environment, the coordinate system points approximating hip, knee and ankle centers in coronal two dimensional images of a first set of two dimensional images;

b) generate in a computer environment a three dimensional knee computer model from a second set of two dimensional images;

c) employ computer processing to cause the three dimensional knee computer model and the coordinate system points to be positioned relative to each other as a combined computer model in a global coordinate system generally as if the three dimensional knee computer model were generated from the first set of two dimensional images;

d) preoperatively plan an arthroplasty procedure with the combined computer model of step c) via a method including;

define a mechanical axis across the three dimensional knee computer model between a pair of the coordinate system points including the coordinate system point approximating the knee center and at least one of the coordinate system points approximating the hip center or approximating the ankle center; and

define a resection plane parallel to, and offset a distance along the mechanical axis from, a reference plane that;

1) is orthogonal to the mechanical axis in a coronal view and

2) extends through a condylar point on the three dimensional knee computer model, wherein the condylar point is either a most distal femoral condyle point or a tibial condyle point; and

e) manufacture the custom arthroplasty resection guide by using data associated with the resection plane to define a resection guide in the custom arthroplasty resection guide.

18. The method of claim 17, further comprising generating the first set of two dimensional images via MRI body coil imaging.

19. The method of claim 18, further comprising generating the second set of two dimensional images via MRI knee coil imaging.

20. The method of claim 17, wherein step c) includes:

determining a first set of locations in the first set of two dimensional images for a set of knee landmarks;

determining a second set of locations in the second set of two dimensional images for the set of knee landmarks; and

employing computer processing in running a transformation process for the first and second sets of locations to generally positionally match the first and second sets of locations in the global coordinate system.

21. The method of claim 20, wherein the transformation employs an Iterative Closest Point algorithm or gradient descent optimization.

22. The method of claim 20, wherein the transformation causes the second set of two dimensional images to reposition in the global coordinate system to the location and orientation of the first set of two dimensional images.

23. The method of claim 17, wherein the three dimensional knee computer model includes a three dimensional femur bone computer model and the mechanical axis is a femoral mechanical axis.

24. The method of claim 23, wherein the condylar point is the most distal femoral condylar point.

25. The method of claim 17, wherein the three dimensional knee computer model includes a three dimensional tibia bone computer model and the mechanical axis is a tibial mechanical axis.

26. The method of claim 25, wherein the condylar point is the tibial condylar point.

27. The method of claim 17, wherein the three dimensional knee computer model includes at least one of a bone-only model or an arthritic model including bone and cartilage.

28. The method of claim 27, wherein the arthritic model is an overestimated model with surface boundaries pushed outwardly from an interior of the overestimated model in areas of the overestimated model corresponding to areas resulting from poor accuracy due to limitations in at least one of imaging limitations or manufacturing limitations.

29. The method of claim 17, in which an image spacing of the first set of two dimensional images is different from an image spacing of the second set of two dimensional images.

30. The method of claim 17, wherein the three dimensional knee computer model includes a three dimensional femur computer model, and the coordinate system point approximating the knee center includes an approximate femur knee center, and the coordinate system point approximating the hip center includes an approximate hip center.

31. The method of claim 30, wherein the approximate femur knee center is close to a medial-lateral center of a distal femur intercondylar groove.

32. The method of claim 31, wherein the approximate hip center is at a center of a femur head.

33. The method of claim 17, wherein the three dimensional knee computer model includes a three dimensional tibia computer model, and the coordinate system point approximating the knee center includes an approximate tibia knee center, and the coordinate system point approximating the ankle center includes an approximate ankle center.

34. The method of claim 33, wherein the approximate tibia knee center is close to a medial-lateral center of a proximal tibia spine.

35. The method of claim 34, wherein the approximate ankle center is close to a cortical bone rim of an ankle plafond.