Methods and devices for spinal screw insertion

Patent metadata

Field	Value
Publication number	US-9855087-B2
Application number	US-201414450952-A
Country	US
Kind code	B2
Filing date	Aug 4, 2014
Priority date	Aug 4, 2014
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

Surgical instruments and methods for delivering bone anchor assemblies into bone are disclosed herein. Use of these anchors or instruments can eliminate one or more of the steps in a conventional bone anchor installation procedure, improving surgical efficiency and safety. In general, a surgical instrument can include a handle assembly having an elongate shaft extending distally therefrom. The handle assembly can be configured to axially translate a stylet extending therethrough relative to a bone anchor assembly coupled to the elongate shaft, and it can be configured to move the stylet proximally in response to distal advancement of a bone anchor assembly into bone. The surgical instruments can include various mechanisms for adjusting the position of the stylet.

First claim

What is claimed is:

1. An instrument for driving a bone anchor assembly into bone, comprising:
an elongate shaft having a distal tip configured to couple to a bone anchor assembly;
a handle assembly coupled to a proximal end of the shaft and including first and second handles rotatably coupled to one another;
a stylet extending through an inner lumen of the handle assembly and the elongate shaft; and
a carrier entirely disposed within the handle assembly, wherein rotation of the first handle while the second handle is held stationary causes the carrier to non-rotatably translate axially relative to the elongate shaft in a proximal direction through the handle assembly to move the stylet proximally and causes rotation of the elongate shaft to drive the bone anchor assembly into bone.

2. The instrument of claim 1 , wherein rotation of the second handle while the first handle is held stationary causes the carrier to rotatably translate relative to the first handle.

3. The instrument of claim 2 , wherein the first handle is positioned distal to the second handle.

4. The instrument of claim 1 , wherein the carrier is configured to rotatably translate relative to and within the handle assembly to adjust a longitudinal position of the stylet relative to the elongate shaft.

5. The instrument of claim 1 , further comprising a stylet holder coupled to the carrier and releasably engaged to the stylet, the stylet holder allowing axial translation of the stylet therethrough when the stylet holder is in a first position relative to the carrier, and the stylet holder preventing axial translation of the stylet therethrough when the stylet holder is in a second position relative to the carrier.

6. The instrument of claim 1 , further comprising a bone anchor assembly matable to the distal tip of the elongate shaft and having threads formed thereon that define an insertion rate of the bone anchor assembly into bone, and wherein the carrier is configured to translate within the handle assembly at a rate that is equal to the insertion rate of the bone anchor assembly.

7. An instrument for driving a bone anchor assembly into bone, the instrument comprising:
an elongate shaft having a proximal and distal ends, a mating feature formed on the distal end and configured to mate to a bone anchor assembly, and an inner lumen extending through the elongate shaft;
a stylet extending through the inner lumen of the elongate shaft; and
a handle assembly coupled to the elongate shaft, the handle assembly including
a proximal handle configured to rotate the elongate shaft to drive a bone anchor assembly coupled to the mating feature on the distal end of the elongate body into body,
a distal handle rotatable relative to the proximal handle, and
a carrier threadably and entirely disposed within the handle assembly and configured to move axially relative to the elongate shaft in response to rotation of one of the proximal and distal handles relative to the other one of the proximal and distal handles to cause the stylet to translate axially relative to the elongate shaft.

8. The instrument of claim 7 , wherein rotation of the proximal handle while the distal handle is held stationary causes rotation of the elongate shaft, and rotation and axial translation of the carrier within the handle assembly.

9. The instrument of claim 7 , wherein rotation of the distal handle while the proximal handle is held stationary causes the carrier to translate axially within the handle assembly without rotating the elongate shaft.

10. The instrument of claim 7 , wherein the proximal handle is mated to the proximal end of the elongate shaft, and the distal handle is rotatably disposed about a proximal portion of the elongate shaft at a location distal to the proximal handle.

11. The instrument of claim 7 , wherein the carrier is threadably coupled to threads formed within the distal handle.

12. The instrument of claim 7 , wherein the stylet is integrally formed on and extends distally from the carrier.

13. The instrument of claim 7 , wherein the stylet is removably mated to the carrier by a mating element.

14. The instrument of claim 7 , further comprising a stylet holder disposed within the handle assembly and having the stylet extending therethrough.

15. The instrument of claim 14 , wherein the stylet holder has a first position, in which the stylet is freely slidable relative to the stylet holder, and a second position in which the stylet holder rigidly engages the stylet to prevent movement of the stylet relative to the stylet holder.

16. The instrument of claim 15 , wherein the stylet holder is configured to be advanced into the carrier to cause the stylet holder to move from the first position to the second position.

17. The instrument of claim 16 , wherein the stylet holder includes a clamping feature that is compressed by the carrier in the second position to cause the clamping feature to rigidly engage the stylet.

18. The instrument of claim 7 , wherein the elongate shaft includes a proximal portion with at least one slot extending therealong, the proximal portion extending through the distal handle and having a proximal end mated to the proximal handle.

19. The instrument of claim 18 , wherein the carrier is slidably disposed within the proximal portion, and the carrier is non-rotatable relative to the proximal portion such that the carrier and the elongate shaft rotate together.

20. The instrument of claim 18 , wherein the carrier includes one or more threaded features that extend through the at least one slot, the at least one slot allowing translation while preventing rotation of the carrier within the proximal portion of the elongate shaft.

21. The instrument of claim 7 , further comprising a protective sleeve removably disposed around the elongate shaft.

22. The instrument of claim 7 , further comprising a positioning handle coupled to a proximal end of the stylet that is configured to adjust a length of stylet that extends from a bone anchor assembly coupled to the distal end of the elongate shaft.

23. The instrument of claim 22 , wherein the positioning handle includes a tool feature for engaging a stylet holder disposed within the handle assembly and having the stylet extending therethrough, the tool feature being configured to advance the stylet holder into the carrier to cause the stylet holder to move from a first position to a second position, wherein the second position locks the stylet to the stylet holder.

24. The instrument of claim 23 , wherein the positioning handle includes an outer housing encompassing at least a part of a positioning feature that secures the proximal end of the stylet to the positioning handle.

25. The instrument of claim 24 , wherein the positioning feature includes a push button that releasably engages an engagement position along the outer housing, the positioning feature being configured to move with the stylet relative to the outer housing when the push button is disengaged from the engagement position.

26. An instrument for driving a bone anchor assembly into bone, the instrument comprising;
an elongate shaft having a proximal and distal ends, a mating feature formed on the distal end and configured to mate to a bone anchor assembly, and an inner lumen extending through the elongate shaft;
a handle assembly coupled to the elongate shaft, the handle assembly including
a distal handle coupled to the pr

Assignees

• Depuy Synthes Products Llc

Inventors

• Divincenzo John
• Pavento Nicholas

Classifications

• A61B17/8875 Primary

  Screwdrivers, spanners or wrenches · CPC title

• A61B17/7091

  for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges · CPC title

• A61B17/7082 Primary

  for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws · CPC title