ENDPLATE PREPARATION INSTRUMENT

• US 20090275943A1
• Filed: 05/05/2008
• Published: 11/05/2009
• Est. Priority Date: 05/05/2008
• Status: Active Grant

• Current Assignee: Ranier Limited
• Original Assignee: Ranier Limited
• Inventors: Snell, Robert, Andrews, Geoffrey Thomas, Johnson, Scott, Lawson, Jonathan
• Granted Patent: US 8,262,663 B2
• Time in Patent Office: Days
• US Class Current: 606/53
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine

Abstract

An instrument for preparation of vertebral endplates and a method of preparing a surface of a vertebral endplate are described. The instrument includes a body having a frame, an endplate preparation member supported by the body, and a pivot point. A tilt axis is perpendicular to and intersects a sweep axis at the pivot point. The endplate preparation member is coupled to the frame and controllably pivotable in an arc about the first tilt axis to change a tilt of the endplate preparation member. The endplate preparation member is also controllably pivotable in an arc about the sweep axis while maintaining the tilt of the endplate preparation member. By sweeping the endplate preparation member at incrementally larger tilt angles, recesses in a vertebral endplate surface are gradually formed, which may allow greater precision and control of a depth of the recesses and reduce stress on the vertebral endplate, as opposed to more aggressive techniques.

Claims

1. A surgical instrument for preparing a surface of a vertebra, the instrument comprising:

an elongated body including a frame;

a first pivot point, wherein a first sweep axis and a first tilt axis that is substantially perpendicular to the first sweep axis pass through the first pivot point; and

a first endplate preparation member for preparing a surface of a vertebra that is supported by the body and that is controllably pivotable in an arc about the first tilt axis to change a tilt of the first endplate preparation member, and is controllably pivotable in an arc about the first sweep axis while maintaining a tilt of the first endplate preparation member.

2. The instrument of claim 1, wherein the first endplate preparation member is pivotable with respect to the frame about the first tilt axis and pivotable with respect to the frame about the first sweep axis.

3. The instrument of claim 1, wherein the first endplate preparation member is pivotably coupled to the frame.

4. The instrument of claim 1, further comprising:

a second pivot point, wherein a second sweep axis and a second tilt axis that is substantially perpendicular to the second sweep axis intersect at the second pivot point; and

a second endplate preparation member for preparing a surface of a vertebra that is controllably pivotable in an arc about the second tilt axis to change a tilt of the second endplate preparation member, and is controllably pivotable in an arc about the second sweep axis while maintaining a tilt of the second endplate preparation member.

5. The instrument of claim 4, wherein the second sweep axis has substantially a same position and a same orientation as the first sweep axis.

6. The instrument of claim 1, wherein the first endplate preparation member is controllably pivotable about the first tilt axis and about the first sweep axis simultaneously.

7. The instrument of claim 1, wherein the first pivot point is able to move along the first sweep axis changing a height of the first endplate preparation member with respect to the frame.

8. The instrument of claim 1, wherein an inner width of the frame at the distal portion of the instrument at least partially determines a total angular sweep range for the first endplate preparation member.

9. The instrument of claim 1, wherein a sweep range of the first endplate preparation member is at least about ±

1 degree or a total sweep range is at least about 2 degrees.

10. The instrument of claim 1, wherein a tilt range for the first endplate preparation member is at least about 1 degree.

11. The instrument of claim 1, wherein the first endplate preparation member is configured to be detached from the instrument.

12. The instrument of claim 1, wherein the first endplate preparation member is detachably connected with the frame.

13. The instrument of claim 1, wherein a preparation member unit of the instrument is removable and replaceable, and wherein the preparation member unit comprises:

the first endplate preparation member;

a mounting element configured to engage a corresponding mounting portion disposed on the frame; and

a first preparation member-frame coupling that pivotably couples the first endplate preparation member and the mounting element.

14. The instrument of claim 13, wherein the preparation member unit further comprises:

a second endplate preparation member; and

a second preparation member-frame coupling that pivotably couples the second endplate preparation member and the mounting element.

15. The surgical instrument of claim 1, further comprising a first arm that is controllably pivotable with respect to the frame and configured to cooperate with the first endplate preparation member for controllably pivoting the first endplate preparation member about the first sweep axis.

16. The surgical instrument of claim 1, further comprising an actuator that is coupled with the frame, that is configured to cooperate with the first endplate preparation member, configured to controllably pivot the first endplate preparation member about the first sweep axis, and configured to controllably pivot the first endplate preparation member about the first tilt axis.

17. A surgical instrument for preparing a surface of a vertebra, the instrument comprising:

an elongated body having a frame;

a first pivot point, wherein a first sweep axis passes through the first pivot point; and

a first endplate preparation member for preparing a surface of vertebra that is supported by the body and that is controllably pivotable in an arc about the first sweep axis though a predetermined sweep range of greater than about 2 degrees and less that about 180 degrees, and is able to be displaced along the first sweep axis changing a height of the first endplate preparation member.

18. The surgical instrument of claim 17, wherein the first endplate preparation member is pivotably coupled to the frame.

19. The surgical instrument of claim 17, wherein the predetermined sweep range is at least partially determined by an inner width of the frame.

20. The surgical instrument of claim 17, wherein a first tilt axis is substantially perpendicular to the first sweep axis and intersects the first sweep axis at the first pivot point;

and wherein the first endplate preparation member is controllably pivotable in an arc about the first tilt axis.

21. The surgical instrument of claim 17, wherein the first pivot point is located on an extendable pin that couples with the frame.

22-54. -54. (canceled)

55. A method of preparing a vertebral endplate, the method comprising:

providing a vertebral endplate preparation instrument having a first endplate preparation member disposed at a distal portion of the instrument;

inserting the distal portion of the instrument into a disc space adjacent to a vertebral endplate;

pivoting the first endplate preparation member relative to the vertebral endplate about a first tilt axis; and

pivoting the first endplate preparation member relative to the vertebral endplate about a first sweep axis that is substantially perpendicular to the first tilt axis while the first endplate preparation member is in contact with the first vertebral endplate surface.

56. The method of claim 55, wherein the vertebral endplate preparation instrument includes a frame, and wherein the frame is held stationary with respect to the vertebral endplate while the first endplate preparation member is pivoted with respect to the vertebral endplate.

57. The method of claim 55, further comprising:

setting the instrument to controllably maintain the first desired tilt angle.

58. The method of claim 55, wherein the instrument is in a collapsed configuration when the distal portion of the instrument is inserted into the disc space.

59. The method of claim 55, further comprising:

pivoting the first endplate preparation member about the first tilt axis until the instrument is in a collapsed configuration; and

removing the distal portion of the instrument from the disc space while maintaining the instrument in a collapsed configuration.

60. The method of claim 55, wherein the first endplate preparation member is pivoted about the first tilt axis until a desired tilt angle is reached.

61. The method of claim 59, further comprising:

pivoting the first endplate preparation member about the first tilt axis until a second desired tilt angle that is larger than the first desired tilt angle is reached; and

pivoting the first endplate preparation member about the first sweep axis while maintaining the second desired tilt angle.

62. The method of claim 55, wherein the endplate preparation instrument further comprises a second endplate preparation member disposed at the distal portion of the instrument;

and

wherein the method further comprises;

pivoting the second endplate preparation member about a second tilt axis; and

pivoting the second endplate preparation member relative to the vertebral endplate about a second sweep axis that is substantially perpendicular to the second tilt axis while the second endplate preparation member is in contact with a surface of a second vertebral endplate opposite the first vertebral endplate.

63. An instrument for preparation of a surface of a vertebral endplate, the instrument comprising:

a first endplate preparation member disposed at a distal portion of the instrument;

means for pivoting the first endplate preparation member the vertebral endplate about a first tilt axis; and

means for pivoting the first endplate preparation member relative to the vertebral endplate about a first sweep axis that is substantially perpendicular to the first tilt axis while the first endplate preparation member is in contact with the vertebral endplate surface.

64. The instrument of claim 63, further comprising:

means for setting the instrument to controllably maintain a tilt angle.

65. The instrument of claim 63, wherein the means for pivoting the first endplate preparation member about the first tilt axis allow a configuration of the instrument to be changed to a collapsed configuration.

66. The instrument of claim 63, wherein the means for pivoting the first endplate preparation member about the first sweep axis and the means for pivoting the first endplate preparation member about the first tilt axis allow the first endplate preparation member to be pivoted about the first sweep axis and pivoted about the first tilt axis simultaneously.