Navigation systems and methods for indicating and reducing line-of-sight errors

• US 10,531,925 B2
• Filed: 01/17/2017
• Issued: 01/14/2020
• Est. Priority Date: 01/16/2013
• Status: Active Grant

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Corporation
• Inventors: Malackowski, Donald W., Moctezuma de la Barrera, Jose Luis
• Primary Examiner(s): Chang, Olivia C
• Application Number:
  US15/407,639
• Publication Number:
  US 20170119478A1
• Time in Patent Office: 1,092 Days
• CPC Class Codes: A61B 17/8057 the interlocking form comprising a thread
• CPC Class Codes: A61B 17/808 Instruments for holding or positioning bone plates, or for adjusting screw-to-plate locking mechanisms
• CPC Class Codes: A61B 17/809 with bone-penetrating elements, e.g. blades or prongs bone staples A61B17/0642; intramedullary nails with a plate at an end A61B17/7233
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 17/92 Impactors or extractors, e.g. for removing intramedullary devices insertion or extraction of artificial joints A61F2/4603
• CPC Class Codes: A61B 2017/00115 with audible or visual output with imaging means A61B90/37, A61B34/20
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2034/2048 using an accelerometer or inertia sensor
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2063 Acoustic tracking systems, e.g. using ultrasound
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• CPC Class Codes: A61B 2090/3991 having specific anchoring means to fixate the marker to the tissue, e.g. hooks
• 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 34/30 Surgical robots
• CPC Class Codes: A61B 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis

Abstract

Navigation systems and methods used to track objects moving in space. One navigation system and method employs trackers having light emitters for indicating when line-of-sight between tracking elements on the trackers and sensors is obstructed or for other errors. Another navigation system and method instructs users on how to place a tracker with respect to an object to reduce line-of-sight issues during a surgical procedure.

Claims

1. A navigation system comprising:

a tracking device including;

a base attachable to an object;

a tracking element; and

a connector coupling said tracking element to said base to allow movement of said tracking element in at least one degree of freedom relative to said base to place said tracking element in a desired orientation;

a computing system configured to;

determine if said tracking element is in the desired orientation; and

in response to determining that said tracking element is not in the desired orientation, instruct a user to move said tracking element relative to said base in said at least one degree of freedom to guide placement of said tracking element to the desired orientation; and

a display, wherein said computing system is configured to instruct the user to move said tracking element relative to said base by displaying instructions on said display.

2. The navigation system as set forth in claim 1 including an orientation sensor to determine if said tracking element is in the desired orientation.

3. The navigation system as set forth in claim 2 wherein said orientation sensor is further defined as a gravity sensor configured to measure gravity components along three axes.

4. The navigation system as set forth in claim 3 wherein said tracking element is capable of generating a line-of-sight tracking signal having a central signal axis and said computing system is configured to instruct the user to move said tracking element in said at least one degree of freedom in order to place the central signal axis in a position generally perpendicular to a direction of gravity.

5. The navigation system as set forth in claim 4 including a camera unit having at least one sensor capable of receiving the line-of-sight tracking signal from said tracking element.

6. The navigation system as set forth in claim 1 wherein said tracking device includes a tracking head supporting said tracking element, said tracking head being movable relative to said base to place said tracking element in the desired orientation.

7. The navigation system as set forth in claim 6 including second and third tracking elements supported by said tracking head.

8. The navigation system as set forth in claim 7 wherein each of said tracking elements are light emitting diodes.

9. The navigation system as set forth in claim 7 wherein each of said tracking elements are reflector balls.

10. The navigation system as set forth in claim 7 wherein each of said tracking elements are line-of-sight tracking elements.

11. The navigation system as set forth in claim 1 wherein said tracking device includes a gyroscope.

12. The navigation system as set forth in claim 1 wherein said tracking element is one of an optical marker, radio frequency receiver, radio frequency transmitter, magnetic field sensor, magnetic field generator, ultrasonic sensor, or ultrasonic transmitter.

13. The navigation system as set forth in claim 1 wherein said tracking device is attachable to bone.

14. The navigation system as set forth in claim 1 wherein said connector is configured to allow movement of said tracking element in two degrees of freedom relative to said base to place said tracking element in the desired orientation.

15. The navigation system as set forth in claim 1, wherein said computing system is further configured to display instructions on said display by graphically representing a current orientation of said tracking element on said display and by dynamically adjusting the graphical representation as the user moves said tracking element.

16. The navigation system as set forth in claim 15, wherein said computing system is further configured to graphically represent the desired orientation on said display so that the user can visually determine how close the current orientation is to the desired orientation.

17. A method of setting up a navigation system to track an object wherein the navigation system comprises:

a tracking device including;

a base attachable to an object a tracking element and a connector coupling the tracking element to the base to allow movement of the tracking element in at least one degree of freedom relative to the base to place the tracking element in a desired orientation;

a computing system configured to;

determine if the tracking element is in the desired orientation; and

in response to determining that the tracking element is not in the desired orientation, instruct a user to move the tracking element relative to the base in the at least one degree of freedom to guide placement of the tracking element to the desired orientation; and

a display, wherein the computing system is configured to instruct the user to move the tracking element relative to the base by displaying instructions on the display,

said method comprising the steps of;

attaching the base to the object;

determining, by using the computing system, if the tracking element is in the desired orientation; and

instructing, by using the computing system, the user to move the tracking element relative to the base in the at least one degree of freedom if the tracking element is not in the desired orientation, wherein instructing the user to move the tracking element relative to the base includes displaying instructions on the display of the navigation system.

18. The method as set forth in claim 17 wherein determining if the tracking element is in the desired orientation includes determining an orientation of the tracking element with respect to gravity.

19. The method as set forth in claim 18 wherein determining an orientation of the tracking element with respect to gravity includes measuring gravity components along x, y, and z axes.

20. The method as set forth in claim 17 including the tracking element generating a line-of-sight tracking signal having a central signal axis and instructing the user to move the tracking element in the at least one degree of freedom in order to place the central signal axis in a position generally perpendicular to a direction of gravity.

21. The method as set forth in claim 20 including receiving the line-of-sight tracking signal with a camera unit of the navigation system.

22. The method as set forth in claim 17 wherein determining if the tracking element is in the desired orientation includes determining if a rotational position of the tracking element is in a desired rotational position.

23. The method as set forth in claim 17 wherein determining if the tracking element is in the desired orientation includes transmitting a signal from the tracking element and a plurality of additional tracking elements to a camera unit of the navigation system to determine a current orientation of the tracking elements.

24. The method as set forth in claim 17 wherein instructing the user to move the tracking element relative to the base includes instructing the user to move the tracking element until a z-axis gravity component measurement is approximately zero.

25. The method as set forth in claim 17 wherein instructing the user to move the tracking element relative to the base includes instructing the user to adjust a tilt position and a rotational position of a tracking head of the tracking device relative to the base, wherein the tracking head supports the tracking element.

26. The method as set forth in claim 25 wherein instructing the user to adjust the tilt position and the rotational position of the tracking head includes first instructing the user to adjust the tilt position and thereafter instructing the user to adjust the rotational position.

27. The method as set forth in claim 17 wherein instructing the user to move the tracking element relative to the base in the at least one degree of freedom includes instructing the user to move the tracking element in two degrees of freedom relative to the base to place the tracking element in the desired orientation.

28. The method as set forth in claim 17 including graphically representing a current orientation of the tracking element on the display of the navigation system and dynamically adjusting the graphical representation as the user moves the tracking element.

29. The method as set forth in claim 28 including graphically representing the desired orientation on the display so that the user can visually determine how close the current orientation is to the desired orientation.

30. The method as set forth in claim 29 including indicating when the tracking element is in the desired orientation.

31. The method as set forth in claim 30 wherein indicating when the tracking element is in the desired orientation includes visually indicating when the tracking element is in the desired orientation.

32. The method as set forth in claim 17 including moving a tracking head of the tracking device relative to the base to place the tracking element in the desired orientation, wherein the tracking head supports the tracking element.

33. The method as set forth in claim 32 including actuating the connector to fix a current orientation of the tracking element after the tracking element is moved to the desired orientation.

34. The method as set forth in claim 17 wherein attaching the base to the object includes attaching the base to bone.