METHOD OF DETERMINING A CONTOUR OF AN ANATOMICAL STRUCTURE AND SELECTING AN ORTHOPAEDIC IMPLANT TO REPLICATE THE ANATOMICAL STRUCTURE

• US 20090048597A1
• Filed: 08/14/2008
• Published: 02/19/2009
• Est. Priority Date: 08/14/2007
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Heavener, Jackson R., May, Justin J.
• Granted Patent: US 9,179,983 B2
• Time in Patent Office: Days
• US Class Current: 606/53
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations

Abstract

A computer assisted surgery (CAS) system and method for preparing an anatomical structure to receive an orthopaedic implant. The method generally involves the steps of determining a contour of the anatomical structure by using the CAS system to acquire a plurality of points on the anatomical structure and provide a best fit approximation of the anatomical structure based on the plurality of points, selecting an implant to replicate the anatomical structure, and preparing the anatomical structure to receive the implant.

Claims

1. A method of selecting a placement of an implant for an orthopaedic surgery, the method comprising the steps of:

identifying a region of an anatomical structure for replacement by said implant;

receiving a plurality of data points corresponding to a contour of said region of said anatomical structure;

selecting said implant from a library of implants, said implant being selected based on said contour of said region of said anatomical structure; and

providing a proposed placement of said implant relative to said anatomical structure.

2. The method of claim 1, further comprising the step of providing an indication of a fit between a contour of said implant and said contour of said region of said anatomical structure.

3. The method of claim 1, further comprising the step of receiving a revised placement of said implant relative to said anatomical structure.

4. The method of claim 1, wherein the step of receiving said plurality of data points includes the steps of:

receiving an indication that a pointer device is positioned at a first position;

determining a first coordinate of said first position; and

determining a second coordinate of a second position.

5. The method of claim 4, wherein the step of determining said second coordinate of said second position is performed in response to receiving an indication that said pointer device is positioned at said second position.

6. The method of claim 4, wherein the step of determining said second coordinate of said second position including the step of waiting a predetermined time interval from determining said first coordinate of said first position, said pointer device being moved by an operator during said predetermined time interval.

7. The method of claim 1, wherein the step of receiving said plurality of data points includes the steps of:

obtaining preoperative representations of said region of said anatomical structure; and

determining said plurality of data points from said preoperative representations of said region of said anatomical structure.

8. The method of claim 1, wherein said contour is determined from a fitting of said plurality of data points to a surface.

9. The method of claim 1, further comprising the step of receiving at least one constraint on said proposed placement of said implant relative to said anatomical structure.

10. The method of claim 9, wherein said at least one constraint is related to an orientation of said implant relative to said anatomical structure.

11. The method of claim 9, wherein said at least one constraint is related to a location of a top surface of said implant relative to said anatomical structure.

12. The method of claim 1, wherein the step of selecting said implant from said library of implants includes the step of receiving a selection of said implant from a user input device.

13. The method of claim 1, wherein the step of selecting said implant from said library of implants includes the step of comparing a contour of each of a plurality of implants to said contour of said anatomical structure, said implant being selected in response to said contour of said implant most closely matching said contour of said anatomical structure.

14. The method of claim 1, further comprising the step of generating a resection plan for said anatomical structure based on said implant.

15. A method of selecting a placement of an implant for an orthopaedic surgery, the method comprising the steps of:

identifying a region of an anatomical structure for replacement by said implant;

determining a contour of said region of said anatomical structure;

for each of a plurality of implants determining a fit between a contour of said respective implant and said contour of said anatomical structure; and

receiving an indication of a selected implant from said plurality of implants.

16. The method of claim 15, wherein said plurality of implants is selected from a library of implants.

17. The method of claim 16, wherein each of said plurality of implants are selected based on satisfying at least one constraint related to said anatomical structure.

18. The method of claim 16, further comprising the step of for each of said plurality of implants determining a resection plan for said anatomical structure, wherein said selected implant is selected from said plurality of implants based on said resection plan for said selected implant.

19. A method of selecting the placement of an implant for an orthopaedic surgery, the method comprising the steps of:

identifying a region of an anatomical structure for replacement by said implant;

determining a contour of said region of said anatomical structure;

obtaining a blank implant for implantation in said anatomical structure;

determining a resection plan for said blank implant; and

machining a top portion of said blank implant to generally match said contour of said region of said anatomical structure.

20. The method of claim 19, further comprising the steps of:

resecting said anatomical structure based on said resection plan; and

implanting said blank implant in said anatomical structure.

21. The method of claim 20, wherein the step of implanting said blank implant in said anatomical structure occurs prior to the step of machining said top portion of said blank implant to match said contour of said region of said anatomical structure.

22. The method of claim 20, wherein the step of implanting said blank implant in said anatomical structure occurs subsequent to the step of machining said top portion of said blank implant to match said contour of said region of said anatomical structure.

23. A method of selecting a placement of an implant for an orthopaedic surgery, the method comprising the steps of:

identifying a region of a current anatomical structure for replacement by said implant;

determining a current contour of said region of said current anatomical structure;

comparing said current contour of said current anatomical structure to a library of contours of anatomical structures;

selecting a first contour of a first anatomical structure from said library of contours of anatomical structures; and

selecting a first implant for implantation in said current anatomical structure, said first implant having been implanted in said first anatomical structure.

24. The method of claim 23, wherein a placement of said first implant relative to said current anatomical structure corresponds to a placement of said first implant relative to said first anatomical structure.

25. The method of claim 24, further comprising the step of determining a resection plan for said first implant for said current anatomical structure.

26. The method of claim 23, wherein said first contour is selected based on said first contour being closest to said current contour than the remainder of said library of contours.

27. The method of claim 23, wherein said first contour is selected based on said first contour having a first constraint which matches a constraint for said current anatomical structure.

28. The method of claim 27, wherein said first contour is selected based on said first contour being closest to said current contour than the remainder of said library of contours.

29. A method of orthopaedic surgery for use with an anatomical structure, comprising the steps of:

acquiring a plurality of data points from said anatomical structure;

determining an approximation of a contour of said anatomical structure based on said plurality of data points;

selecting a first orthopaedic implant from a plurality of orthopaedic implants for said anatomical structure based on said determined contour of said anatomical structure;

preparing said anatomical structure to receive said first orthopaedic implant; and

coupling said first orthopaedic implant to said anatomical structure.

30. The method of claim 29, wherein said acquiring step comprises contacting a pointer device to said anatomical structure at a plurality of locations.

31. The method of claim 29, wherein said acquiring step comprises obtaining said data points based on a preoperative plan.

32. A method of orthopaedic surgery for use with an anatomical structure, comprising the steps of:

acquiring a plurality of data points from said anatomical structure;

using said plurality of data points to calculate a best fit approximation of a contour of said anatomical structure;

selecting an orthopaedic implant substantially matching said contour of said anatomical structure;

preparing said anatomical structure to receive said orthopaedic implant; and

implanting said orthopaedic implant in said anatomical structure.

33. The method of claim 32, wherein said acquiring step comprises contacting a pointer device to said anatomical structure at a plurality of locations.

34. The method of claim 32, wherein said acquiring step comprises obtaining said data points based on a preoperative plan.