SYSTEM AND METHOD FOR ROBOTIC SURGERY

• US 20130096574A1
• Filed: 10/18/2011
• Published: 04/18/2013
• Est. Priority Date: 10/18/2011
• Status: Active Grant

• Current Assignee: MAKO Surgical Corporation (Stryker Corporation)
• Original Assignee: MAKO Surgical Corporation (Stryker Corporation)
• Inventors: Kang, Hyosig, Nortman, Scott
• Granted Patent: US 9,060,794 B2
• Time in Patent Office: Days
• US Class Current: 606/130
• CPC Class Codes: A61B 17/16 Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans arthroscopic bone cutters A61B17/320016; dental implant drills potentially for other surgical use A61C8/0089; bone grinders A61F2/4644, A22C17/06; A61B17/1662 takes precedence over all other subgroups except A61B17/17
• CPC Class Codes: A61B 17/1622 Drill handpieces A61B17/1626, A61B17/1628 take precedence
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• 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 34/37 Master-slave robots A61B34/35 takes precedence
• CPC Class Codes: A61B 34/75 Manipulators having means for prevention or compensation of hand tremors
• CPC Class Codes: A61B 34/76 Manipulators having means for providing feel, e.g. force or tactile feedback
• CPC Class Codes: A61B 90/03 Automatic limiting or abutting means, e.g. for safety

Abstract

In one embodiment, a robotic surgery system comprises a handheld manipulator configured to be manually moved in a global coordinate system relative to the bone, the handheld manipulator comprising a bone cutting tool comprising an end effector portion, a frame assembly, and a motion compensation assembly movably coupled to the frame assembly and bone cutting tool. A controller may be operatively coupled to the manipulator and configured to operate one or more actuators within the frame assembly to cause the motion compensation assembly to automatically move relative to the frame assembly to defeat aberrant movement of the bone cutting tool that would place the end effector portion of the tool out of a desired bone cutting envelope that is based at least in part upon one or more images of the bone, while allowing the bone cutting tool to continue cutting one or more portions of the bone.

Claims

1. A robotic surgery system for cutting a bone of a patient, comprising:

a. a handheld manipulator configured to be manually moved in a global coordinate system relative to the bone, the handheld manipulator comprising;

1) a bone cutting tool comprising an end effector portion,

2) a frame assembly, and

3) a motion compensation assembly movably coupled to the frame assembly and bone cutting tool; and

b. a controller operatively coupled to the manipulator and configured to operate one or more actuators within the frame assembly to cause the motion compensation assembly to automatically move relative to the frame assembly to defeat aberrant movement of the bone cutting tool that would place the end effector portion of the tool out of a desired bone cutting envelope that is based at least in part upon one or more images of the bone, while allowing the bone cutting tool to continue cutting one or more portions of the bone.

2. The system of claim 1, wherein the end effector portion comprises a burr.

3. The system of claim 1, further comprising a housing coupled to the frame assembly.

4. The system of claim 3, wherein the housing comprises a handle configured to be manually grasped by a human hand.

5. The system of claim 1, wherein the housing is operatively coupled to a gravity compensation mechanism.

6. The system of claim 1, wherein the frame assembly comprises one or more motors operatively coupled to one or more structural members, the one or more structural members being coupled to the motion compensation assembly.

7. The system of claim 6, wherein the one or more structural members are configured to insert and retract relative to the frame assembly, causing an associated movement of the motion compensation assembly.

8. The system of claim 7, wherein the one or more motors are operatively coupled to the one or more structural members via one or more lead screw assemblies configured to insert and retract each of the structural members in accordance with rotation of the one or more motors.

9. The system of claim 8, further comprising one or more belts operatively coupled between each of the one or more motors and one or more lead screw assemblies, the one or more belts configured to transfer rotational motion from the one or more motors to the one or more lead screw assemblies.

10. The system of claim 8, further comprising one or more gears intercoupled between at least one of the one or more lead screw assemblies and one or more motors, the gears configured to transfer rotational motion from the one or more motors to the one or more lead screw assemblies.

11. The system of claim 1, further comprising a tool drive assembly intercoupled between the bone cutting tool and the motion compensation assembly.

12. The system of claim 11, wherein the tool drive assembly comprises a motor configured to actuate the bone cutting tool.

13. The system of claim 12, wherein the motor is configured to controllably move the bone cutting tool.

14. The system of claim 13, wherein the motor is operatively coupled to the controller such that the controller may control or stop a cutting velocity of the bone cutting tool.

15. The system of claim 14, wherein the controller is configured to change the cutting velocity of the bone cutting tool based at least in part upon a signal from a sensor indicating that the end effector portion is being moved toward a boundary of the desired bone cutting envelope.

16. The system of claim 14, wherein the controller is configured to modulate the cutting velocity of the bone cutting tool based at least in part upon the location of the tool within the desired bone cutting envelope.

17. The system of claim 16, wherein the controller is configured to generally reduce the cutting velocity of the bone cutting tool when the tool is moved adjacent an edge of the desired bone cutting envelope.

18. The system of claim 14, wherein the controller is configured to modulate the cutting velocity of the bone cutting tool based at least in part upon the location of the tool within a predetermined workspace of the handheld manipulator.

19. The system of claim 18, wherein the controller is configured to generally reduce the cutting velocity of the bone cutting tool when the tool is moved adjacent the edge of the predetermined workspace.

20. The system of claim 1, further comprising a tracking subsystem configured to determine a position of the end effector portion of the bone cutting tool relative to the global coordinate system.

21. The system of claim 1, further comprising a tracking subsystem configured to determine a position of one or more portions of the desired bone cutting envelope relative to the global coordinate system.

22. The system of claim 1, further comprising a tracking subsystem configured to determine a position of the end effector portion of the bone cutting tool relative to one or more portions of the desired bone cutting envelope.

23. The system of claim 20, wherein the tracking subsystem comprises a tracking element selected from the group consisting of:

a mechanical tracker linkage, an optical tracker, an ultrasonic tracker, and an ultra-wide-band tracker.

24. The system of claim 23, wherein the tracking system comprises a mechanical tracker linkage having at least two substantially rigid portions coupled by at least one movable joint.

25. The system of claim 23, wherein the tracking system comprises a mechanical tracker linkage having at least three substantially rigid portions coupled in a series configuration by two or more movable joints.

26. The system of claim 25, wherein the series configuration comprises a proximal end and a distal end, each of which is coupled to a kinematic quick-connect fitting.

27. The system of claim 26, wherein a proximal kinematic quick-connect fitting is configured to be fixedly and removably coupled to the bone.

28. The system of claim 26, wherein a distal kinematic quick-connect fitting is configured to be fixedly and removably coupled to the frame assembly.

29. The system of claim 1, wherein the controller is configured to defeat aberrant movement of the bone cutting tool that is associated with relatively high frequency unintended motion.

30. The system of claim 29, wherein the relatively high frequency unintended motion has a frequency between about 1 Hz and about 12 Hz.

31. The system of claim 1, wherein the controller is configured to defeat aberrant movement of the bone cutting tool that is associated with relatively low frequency unintended motion.

32. The system of claim 31, wherein the relatively low frequency unintended motion has a frequency between about 0 Hz and about 1 Hz.

33. The system of claim 1, wherein the controller is configured to defeat aberrant movement of the bone cutting tool that is associated with both relatively low frequency unintended motion and relatively high frequency unintended motion.

34. The system of claim 33, wherein the unintended motion has a frequency between about 0 Hz and about 12 Hz.

35. The system of claim 1, wherein the one or more images are acquired using an imaging modality selected from the group consisting of:

computed tomography, radiography, ultrasound, and magnetic resonance.

36. The system of claim 1, wherein the controller is configured to modulate the tool path automatically based at least in part upon potential field analysis.

37. The system of claim 36, wherein the controller is configured to execute modulation of the tool path through motion compensation.

38. The system of claim 36, wherein the controller is configured to execute modulation of the tool path through haptic resistance to motion of the handheld manipulator.

39. A robotic surgery method for cutting a bone of a patient, comprising:

a. acquiring image information regarding the bone;

b. manually moving a handheld manipulator, the handheld manipulator operatively coupled to a bone cutting tool having an end effector portion, to cut a portion of the bone with the end effector portion; and

c. automatically compensating for aberrant movement of the bone cutting tool that would place the end effector portion of the tool out of a desired bone cutting envelope that is based at least in part upon the image information, while allowing the bone cutting tool to continue cutting one or more portions of the bone.

40. The method of claim 39, wherein the handheld manipulator is configured to be manually moved in a global coordinate system relative to the bone.

41. The method of claim 39, wherein the end effector portion is configured to be moved at a preferred bone cutting velocity.

42. The method of claim 39, further comprising modulating the cutting velocity based at least in part upon the location of the end effector portion within a desired bone cutting envelope.

43. The method of claim 42, comprising generally reducing the cutting velocity of the end effector portion when the end effector portion is moved adjacent an edge of a desired bone cutting envelope.

44. The method of claim 39, further comprising modulating the cutting velocity of the end effector portion based at least in part upon the location of the end effector portion within a predetermined workspace of the handheld manipulator.

45. The method of claim 44, comprising generally reducing the cutting velocity of the end effector portion when the end effector portion is moved adjacent an edge of the predetermined workspace of the handheld manipulator.

46. The method of claim 39, wherein the end effector portion is allowed to continue cutting one or more portions of the bone at the preferred cutting angular velocity while automatically compensating for aberrant movement of the bone cutting tool.

47. The method of claim 39, wherein automatically compensating for aberrant movement of the bone cutting tool comprises controllably moving the cutting tool relative to the handheld manipulator.

48. The method of claim 47, wherein controllably moving comprises axially moving the cutting tool in a direction substantially coaxial with a longitudinal axis of a previous position of the cutting tool.

49. The method of claim 47, wherein controllably moving comprises adjusting a pitch or yaw of the cutting tool relative to a longitudinal axis of a previous position of the cutting tool.

50. The method of claim 47, wherein controllably moving comprises moving the cutting tool in two or more degrees of freedom.

51. The method of claim 39, wherein acquiring image information comprises using an imaging modality selected from the group consisting of:

computed tomography, radiography, ultrasound, and magnetic resonance.

52. The method of claim 39, further comprising creating a preoperative surgical plan based at least in part upon the image information, and utilizing the preoperative surgical plan to create the desired bone cutting envelope.

53. The method of claim 47, wherein controllably moving the cutting tool relative to the handheld manipulator comprises operating a motor.

54. The method of claim 53, wherein operating the motor operates a lead screw mechanism operatively coupled to the motor.

55. The method of claim 39, further comprising determining that an attempted movement is an aberrant movement.

56. The method of claim 55, wherein determining that an attempted movement is an aberrant movement comprises tracking the spatial positioning of the bone and the end effector portion of the cutting tool.

57. The method of claim 56, wherein tracking the spatial positioning of the bone comprises monitoring the positions of one or more optical tracking markers that are coupled to the bone.

58. The method of claim 56, wherein tracking the spatial positioning of the bone comprises monitoring the positions of one or more joints of a mechanical tracker linkage that is coupled to the bone.

59. The method of claim 56, wherein tracking the spatial positioning of the end effector portion of the cutting tool comprises monitoring the positions of one or more optical tracking markers that are coupled to the cutting tool.

60. The method of claim 56, wherein tracking the spatial positioning of the end effector portion of the cutting tool comprises monitoring the positions of one or more joints of a mechanical tracker linkage that is coupled to the cutting tool.

61. The method of claim 39, further comprising intercoupling a mechanical tracker linkage between the bone and the handheld manipulator to facilitate monitoring of the three dimensional relative spatial relationship between the bone and the handheld manipulator.

62. The method of claim 61, wherein intercoupling comprises removably coupling at least one end of the mechanical tracker with a kinematic quick-connect fitting.

63. The method of claim 39, further comprising modulating the tool path automatically based at least in part upon potential field analysis.

64. The method of claim 63, wherein modulating the tool path comprises executing motion compensation based upon the potential field analysis.

65. The method of claim 63, wherein modulating the tool path comprises haptically resisting motion of the handheld manipulator.

66. The method of claim 39, further comprising modulating the tool path automatically based at least in part upon a spatial state machine heuristic.

67. A robotic surgery method for cutting a bone of a patient, comprising:

a. characterizing the geometry and positioning of the bone;

b. manually moving a handheld manipulator, the handheld manipulator operatively coupled to a bone cutting tool having an end effector portion, to cut a portion of the bone with the end effector portion; and

c. automatically compensating for aberrant movement of the bone cutting tool that would place the end effector portion of the tool out of a desired bone cutting envelope that is based at least in part upon the image information, while allowing the bone cutting tool to continue cutting one or more portions of the bone.

68. The method of claim 67, wherein characterizing the geometry and position of the bone comprises analyzing image information acquired from the bone.

69. The method of claim 68, further comprising acquiring the image information using a modality selected from the group consisting of:

computed tomography, radiography, ultrasound, and magnetic resonance.