Apparatus and method for improving the accuracy of navigated surgical instrument

• US 20050288679A1
• Filed: 04/06/2005
• Published: 12/29/2005
• Est. Priority Date: 11/17/2000
• Status: Active Grant

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: General Electric Company
• Inventors: Kienzle, Thomas C. III
• Granted Patent: US 8,332,012 B2
• Time in Patent Office: Days
• US Class Current: 606/97
• 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 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2065 Tracking using image or pattern recognition
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/25 User interfaces for surgical systems

Abstract

A computer assisted surgery system is described for assisting a surgeon in aligning a drill with the interlocking holes of an implanted intramedullary (IM) rod used for fixation of long bone fractures. With the IM rod inserted, a localizing device measures the pose of a tracked adapter attached to the rod'"'"'s exposed end. Approximate AP and lateral fluoroscopic x-ray images are acquired of the end of the rod with the interlocking holes. Image processing algorithms determine the actual position of the rod and calculate an adjustment to the pose of the tracked adapter and IM rod. Using the adjusted pose information, the system displays, in three roughly orthogonal views, a representation of the drill trajectory relative to the images of the IM rod and relative to a graphic representation of the IM rod.

Claims

1-13. -13. (canceled)

14. A computer assisted surgery system for accurately positioning an instrument in a body, said system including:

a localizing device configured to measure a pose of a surgical device; and

a computer configured to calculate an adjusted pose for said surgical device, said adjusted pose based on information developed from an image of said surgical device,

wherein said adjusted pose includes a compensation for an improperly positioned representation of said surgical device in a graphical display of said surgical device.

15. The system of claim 14, wherein said surgical device includes at least one of a surgical implant and a surgical instrument.

16. The system of claim 14, wherein said computer is configured to calculate a 3-D adjustment for said surgical device, said 3-D adjustment calculated from a plurality of adjusted poses for said surgical device, said plurality of adjusted poses each based on information developed from one of a plurality of images obtained from different viewpoints.

17. The system of claim 14, further including at least one of a drill guide, a drill guide pin, and a screw aligned with said surgical device.

18. The system of claim 17, wherein said computer is configured to calculate a pose of at least one of said drill guide, said drill guide pin, and said screw relative to said surgical device, said pose adjusted based on said adjusted pose of said surgical device.

19. The system of claim 18, wherein said computer is configured to calculate a 3-D adjustment of said pose, said 3-D adjustment calculated from plurality of adjusted poses of said drill guide, said drill guide pin, and/or said screw, said plurality of adjusted poses each based on information developed from one of a plurality of images obtained from different viewpoints.

20. The system of claim 14, wherein said compensation provides for increased accuracy of a position of said surgical device in said body.

21. The system of claim 14, further including a display configured to display a more accurate representation of said surgical device over said image, said representation based on at least said adjusted pose.

22. The system of claim 14, wherein said graphical display includes a more accurate representation of said surgical device relative to at least one representation of at least one other surgical device.

23. The system of claim 21, wherein said display is configured to display said representation in real time.

24. The system of claim 21, wherein said representation includes a line representative of a trajectory of said surgical device.

25. The system of claim 21, wherein said representation includes at least one of a surface model, a solid model, a bitmap, and a wireframe model of said surgical device.

26. A method for accurately positioning a surgical device in a body, said method including:

generating a computer model of said surgical device, said model including a reference point;

measuring a pose of said surgical device;

acquiring at least one image of said surgical device;

calculating a first position of said reference point based on at least said computer model and said pose of said surgical device;

calculating a second position of said reference point based on at least said at least one image; and

calculating an adjusted pose of said surgical device based on at least a difference between said first and second positions.

27. The method of claim 26, wherein said surgical device includes at least one of a surgical implant and a surgical instrument.

28. The method of claim 26, wherein said step of calculating said adjusted pose includes calculating a 3-D adjustment of said surgical device, said 3-D adjustment calculated from a plurality of adjusted poses for said surgical device, said plurality of adjusted poses each based on information developed from one of a plurality of images obtained from different viewpoints.

29. The method of claim 26, further including aligning at least one of a drill guide, a drill guide pin, and a screw with said surgical device.

30. The method of claim 29, further including determining a pose of at least one of said drill guide, said drill guide pin, and said screw relative to said surgical device.

31. The method of claim 26, further including displaying a more accurate representation of said surgical device over said image, said representation based on at least said adjusted pose.

32. The method of claim 31, wherein said displaying step includes displaying said more accurate representation of said surgical device relative to at least one representation of at least one other surgical device.

33. The method of claim 31, wherein said displaying step occurs in real time.

34. The method of claim 31, wherein said representation includes a line representative of a trajectory of said surgical device.

35. The method of claim 31, wherein said representation includes at least one of a surface model, a solid model, a bitmap, and a wireframe model of said surgical device.

36. A method for improving the accuracy of a navigated surgical instrument, said method including:

acquiring an image of a patient anatomy and said instrument;

generating a graphic representation of said instrument; and

adjusting a position of said representation based on an adjustment transformation, said adjustment transformation based on a positional error of said instrument at or near an end of said instrument.

37. The method of claim 36, wherein said representation of said instrument includes at least one of a surface model, a solid model, a bitmap, and a wireframe model.

38. The method of claim 36, wherein said adjustment transformation is determined by the following steps:

projecting an adjustment axis onto said image;

analyzing image data associated with said image along a segment of said adjustment axis in order to determine a projected center line; and

calculating a difference between said projected center line of said instrument and a measured center line of said instrument.

39. The method of claim 38, further including measuring said measured center line using a localizing device.

40. The method of claim 38, wherein said projected center line corresponds to an origin of a coordinate frame defined relative to an exposed end of said instrument and located on said instrument at or near an end of said instrument inserted into a patient anatomy.

41. The method of claim 36, further including acquiring a plurality of images from different viewpoints,

wherein said adjustment transformation includes a 3-D adjustment for said instrument, said 3-D adjustment calculated from a plurality of adjusted poses for said instrument, said plurality of adjusted poses each based on information developed from one of said plurality of images from different viewpoints.

42. The method of claim 36, wherein said adjusting step includes applying said adjustment transformation to a coordinate frame defined at an interface between said instrument and a tracking device attached to said instrument.