Granted Patent B2

US 11,058,437 · App. 16/370,402 · Granted Jul 13, 2021

Inventors: Allison Christine Capote (Boulder, CO); Adam Costanza (Aurora, CO); David Lee Skaggs (Los Angeles, CA); Frank J. Schwab (New York, NY)

Assignee: Zimmer Biomet Spine, Inc.

A61B17/1631A61B17/1615A61F2/4611A61B17/1757A61B17/70

Abstract

Claims (73)

1. A method of implanting a bone anchor in a vertebra, the method comprising:

engaging a tip of a flexible drill bit with boney structure of the vertebra;

rotating the flexible drill bit at a slow speed;

pushing the drill bit into exterior cortical bone of the boney structure of the vertebra;

guiding the flexible drill bit into cancellous bone of the vertebra;

receiving a tactile output generated by the flexible drill bit indicating resistance of interior cortical bone of the boney structure through the flexible drill bit; and

reorienting a trajectory of the flexible drill bit toward the cancellous bone of the vertebra in reaction to the tactile output;

wherein feeling vibration of the flexible drill bit comprises feeling bending of the flexible drill bit.

2. The method of claim 1 , wherein rotating the flexible drill bit at a slow speed comprises rotating the flexible drill bit with a powered driver.

3. The method of claim 2 , wherein rotating the flexible drill bit at a slow speed comprises rotating the flexible drill bit at approximately one to three revolutions per second.

4. The method of claim 2 , further comprising receiving the tactile output at the powered driver by feeling vibration of the flexible drill bit.

5. The method of claim 1 , wherein bending of the flexible drill bit comprises bending the flexible drill bit between a necked-down shaft portion and a bulbous drill tip.

6. The method of claim 1 , wherein engaging the tip of the flexible drill bit with the boney structure of the vertebra further comprises:

forming a centering hole in the exterior cortical bone of the boney structure; and

engaging the tip of the flexible drill bit with the centering hole.

7. The method of claim 1 , further comprising:

withdrawing the flexible drill bit from the boney structure to leave a bone canal; and

confirming formation of the bone canal with a ball tip probe.

8. The method of claim 1 , further comprising:

withdrawing the flexible drill bit from the boney structure to leave a bone canal;

widening the bone canal with an enlarging drill bit to a diameter of a threaded fastener of the bone anchor; and

inserting the threaded fastener into the widened bone canal.

9. The method of claim 1 , further comprising:

withdrawing the flexible drill bit from the boney structure to leave a bone canal;

widening the bone canal with a reamer to a diameter of a threaded fastener of the bone anchor; and

inserting the threaded fastener into the widened bone canal.

10. The method of claim 1 , further comprising:

withdrawing the flexible drill bit from the boney structure to leave a bone canal; and

inserting a bone anchor into the bone canal, wherein the flexible drill bit has a diameter equal to or smaller than a threaded shaft of the bone anchor.

11. The method of claim 1 , further comprising checking a depth of the flexible drill bit in the vertebra by referencing cortical bone against indicia provided on a flexible portion of the flexible drill bit.

12. The method of claim 9 , wherein inserting the bone anchor into the bone canal comprises:

coupling a sleeve to a driver shaft;

coupling the driver shaft to the bone anchor;

grasping the sleeve;

guiding the driver shaft toward the boney structure to insert the bone anchor into the bone canal;

rotating the driver shaft within the sleeve using a powered driver; and

translating the sleeve along the driver shaft to guide the bone anchor to the bone canal and to receive the tactile output of the flexible drill bit.

13. A method of implanting a pedicle screw into a pedicle of a vertebra, the method comprising:

determining a trajectory for a pedicle screw shaft into a cancellous bone canal behind a cortical bone wall to avoid interior cortical bone;

engaging a tip of a drill bit having a tapered shaft with a starting point of the trajectory on the cortical bone wall of the pedicle of the vertebra;

rotating the drill bit using rotational input from a powered driver;

pushing the powered driver to penetrate the tip of the drill bit through the cortical bone wall along the trajectory;

guiding the drill bit into the cancellous bone canal;

sensing engagement of the tip of the drill bit with the interior cortical bone; and

reorienting the drill bit along the trajectory away from the interior cortical bone,

wherein sensing engagement of the tip of the drill bit comprises receiving a tactile feedback at the powered driver;

wherein the tactile feedback comprises a vibration of the drill bit transmitted to the powered driver; and

wherein the drill bit comprises:

a first shaft portion for coupling to a driver;

a tapered portion extending from the first shaft portion at a first end to a reduced diameter at a second end; and

a second shaft portion extending from the second end of the tapered portion, the second shaft portion having a diameter of in the range of 1.0 mm to 2.0 mm;

wherein the vibration of the drill bit is caused by bending of the second shaft portion of the drill bit.

14. The method of claim 13 , further comprising producing a centering hole in the cortical bone wall at the starting point before engaging the tip of the drill bit with the cortical bone wall.

15. The method of claim 13 , wherein bending of the necked-down shaft of the drill bit causes the tip of the drill bit to deflect away from the interior cortical bone.

16. The method of claim 13 , further comprising:

withdrawing the flexible drill bit from the vertebra to leave a bone canal;

confirming formation of the bone canal with a ball tip probe; and

inserting a bone anchor into the bone canal.

17. The method of claim 1 , wherein the bending occurs proximal of the distal bulbous drill tip.

18. A method of implanting a bone anchor in a vertebra, the method comprising:

engaging a tip of a flexible drill bit with boney structure of the vertebra;

rotating the flexible drill bit at a slow speed;

pushing the drill bit into exterior cortical bone of the boney structure of the vertebra;

guiding the flexible drill bit into cancellous bone of the vertebra;

receiving a tactile output generated by the flexible drill bit indicating resistance of interior cortical bone of the boney structure through the flexible drill bit; and

reorienting a trajectory of the flexible drill bit toward the cancellous bone of the vertebra in reaction to the tactile output;

wherein inserting the bone anchor into the bone canal comprises:

coupling a sleeve to a driver shaft;

coupling the driver shaft to the bone anchor;

grasping the sleeve;

guiding the driver shaft toward the boney structure to insert the bone anchor into the bone canal;

rotating the driver shaft within the sleeve using a powered driver; and

translating the sleeve along the driver shaft to guide the bone anchor to the bone canal and to receive the tactile output of the flexible drill bit.

Assignments (7)