DRIVER INSTRUMENTS AND RELATED METHODS

• US 20190059967A1
• Filed: 08/31/2018
• Published: 02/28/2019
• Est. Priority Date: 04/13/2015
• Status: Active Grant

• Current Assignee: Medos International Sarl (Johnson & Johnson)
• Original Assignee: Medos International Sarl (Johnson & Johnson)
• Inventors: Chandanson, Thibault, Fournier, Richard W., Stad, Shawn D., Spratt, Frank, Grossman, Sam, Defossez, Henri, Rouge, Renaud, Cormier, Philip A.
• Granted Patent: US 11,457,967 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 17/1655 for tapping
• CPC Class Codes: A61B 17/7082 for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws driving other bone screws A61B17/8875
• CPC Class Codes: A61B 17/7098 wherein the implant is permeable or has openings, e.g. fenestrated screw hollow surgical screws A61B17/864
• CPC Class Codes: A61B 17/8816 characterised by the conduit, e.g. tube, along which fluid flows into the body or by conduit connections
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 2017/0046 with a releasable handle; with handle and operating part separable for prosthetic joint-implanting tools A61F2/4603
• CPC Class Codes: B25B 23/0035 Connection means between socket or screwdriver bit and tool

Abstract

Driver instruments are disclosed herein with various features for improving usability, easing the task of cleaning or sterilizing the instrument, reducing patient trauma associated with use of the instrument, and/or reducing the cost and assembly burden of the instrument. For example, a driver instrument can include a guide sleeve to protect patient tissue from damage caused by rotating components of the instrument or a bone anchor assembly coupled thereto, and to protect extension tabs of the bone anchor assembly from inadvertent separation. By way of further example, an instrument can include a preload assembly for maintaining engagement of a driver shaft of the instrument with a bone anchor assembly. As yet another example, an instrument can consist of a small number of components which are configured for simple, tool-free assembly and disassembly. An instrument can also be configured for use with bone anchor assemblies with and without extension tabs.

Claims

1. An instrument for driving a bone anchor assembly into bone, the instrument comprising:

a driver shaft having a distal drive tip and a proximal driven end;

an elongate body having proximal and distal ends that defines a central passage in which the driver shaft is rotatably disposed; and

a release button disposed in the body and having at least a first position in which the driver shaft can be removed from the body and a second position in which the driver shaft cannot be removed from the body.

2. The instrument of claim 1, further comprising a preload assembly configured to bias the driver shaft in a distal direction relative to the body.

3. The instrument of claim 1, wherein a location at which the preload assembly engages the driver shaft can be selected from amongst a plurality of locations to adjust the degree to which the driver shaft protrudes from the distal end of the body.

4. The instrument of claim 3, wherein the plurality of locations are defined by radial projections that extend from the driver shaft.

5. The instrument of claim 1, further comprising a guide sleeve positionable over a distal end of the body and configured to separate the body and the driver shaft from surrounding tissue when the instrument is used to drive a bone anchor assembly into bone.

6. The instrument of claim 5, wherein the sleeve has a flared distal end and a flared proximal end.

7. The instrument of claim 5, wherein the sleeve includes a lever configured to pivot at a fulcrum point to selectively engage and disengage the sleeve with the body.

8. The instrument of claim 5, wherein the lever is formed integrally with the sleeve at a living hinge.

9. The instrument of claim 5, wherein the sleeve is rotatable with respect to the body and with respect to the driver shaft.

10. The instrument of claim 5, wherein the sleeve is configured to engage any of a plurality of mating features spaced longitudinally along the body.

11. The instrument of claim 1, wherein the body includes an engagement portion formed at a distal end thereof, the engagement portion being configured to engage a corresponding engagement portion on a bone anchor assembly.

12. The instrument of claim 1, wherein the release button is disposed in a housing portion of the body, the housing portion having a plurality of openings through which fluid can access the central passage.

13. The instrument of claim 1, wherein the release button includes a cylindrical recess in which a sliding collar is disposed, the driver shaft extending through the sliding collar.

14. The instrument of claim 13, wherein the sliding collar includes a plurality of openings spaced about a sidewall thereof.

15. The instrument of claim 13, further comprising a preload spring disposed between the collar and the release button.

16. An instrument for driving a bone anchor assembly into bone, the instrument comprising:

a driver shaft having a distal drive tip and a proximal driven end;

an elongate body having proximal and distal ends that defines a central passage in which the driver shaft is rotatably disposed;

a release button disposed in the body and having a collar slidably disposed therein, the collar being configured to selectively engage the driver shaft; and

a preload spring disposed between the release button and the collar configured to bias the driver shaft in a distal direction with respect to the body.

17. The instrument of claim 16, wherein the driver shaft includes a plurality of projections extending radially outward therefrom, and wherein the degree to which the driver shaft protrudes from the distal end of the body can be adjusted by selecting which of the plurality of projections engages the collar.

18. A method of driving a bone anchor assembly into bone, comprising:

engaging a drive interface of a bone anchor assembly with a drive tip of a driver shaft;

advancing a body portion in which the driver shaft is rotatably disposed distally with respect to the bone anchor assembly to couple an engagement feature of the body portion with a corresponding engagement feature of the bone anchor assembly, wherein said distal advancement preloads a spring disposed in the body portion;

rotating the driver shaft to drive the bone anchor assembly into bone; and

actuating a release button to disengage the driver shaft from the body portion such that the driver shaft can be removed from the body portion.

19. The method of claim 18, further comprising positioning a guide sleeve disposed over the body portion between extension tabs of the bone anchor assembly and surrounding tissue.

20. The method of claim 18, further comprising selecting from amongst a plurality of positions at which the driver shaft can be engaged by the body portion to adjust a degree to which the driver shaft protrudes from a distal end of the body portion.