System and methods for rod insertion using a screw tower

Patent metadata

Field	Value
Publication number	US-11737795-B1
Application number	US-202217652774-A
Country	US
Kind code	B1
Filing date	Feb 28, 2022
Priority date	Feb 28, 2022
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

A screw tower that is a single-use instrument that attaches to existing screws but remains open along a rod slot to allow for screws to intermesh and prevent interference of adjacent screws during screw and rod insertion. The screw tower interfaces with existing features of the screws to facilitate screw insertion, rod insertion, rod reduction, and locking cap insertion in a percutaneous approach. The tower is broken in half and removed from patient to end with a completed construct.

First claim

What is claimed is:

1. A screw tower, comprising:
a distal end configured to engage a screw;
a proximal end configured to engage instrumentation;
a first half and a second half that are connected at the distal end and separately extend to the proximal end;
a feature set at the distal end configured to engage a head of a screw, wherein the feature set includes a plurality of chevrons each configured to engage the screw for attachment of the tower to the screw, the feature set further including a breakpoint configured to allow the first half and the second half to break apart from each other; and
an instrument insertion feature disposed at the proximal end
wherein the feature set includes a partial diameter truncated by two larger radii that extend to a height to form a tapered or conical surface at the distal end.

2. The screw tower of claim 1 , wherein each chevron is configured to flex out via a relief cut.

3. The screw tower of claim 1 , wherein each of the first half and the second half contain one of the plurality of chevrons.

4. The screw tower of claim 1 , wherein the distal end is laterally trimmed to reduce the profile of the tower.

5. The screw tower of claim 1 , wherein the first half and the second half form a rod slot.

6. The screw tower of claim 5 , wherein a diameter of the distal end is greater than a diameter of the proximal end.

7. The screw tower of claim 5 , wherein the size of the rod slot is greater than a screw head rod slot of the screw.

8. The screw tower of claim 1 , wherein the first half and second half are manufactured as a single piece configured to break apart at the breakpoint.

9. The screw tower of claim 1 , wherein the first half and the second half are welded together at or near the breakpoint.

10. A method of fixating adjacent cervical vertebral bodies, said method comprising:
implanting a screw into a pedicle through an incision, wherein the screw includes a head;
securing a screw tower to the head of the screw, wherein the screw tower includes:
a distal end configured to engage a screw;
a proximal end configured to engage instrumentation;
a first half and a second half that are connected at the distal end and separately extend to the proximal end;
a feature set at the distal end configured to engage a head of a screw, wherein the feature set includes a plurality of chevrons each configured to engage the screw for attachment of the tower to the screw, the feature set further including a breakpoint configured to allow the first half and the second half to break apart from each other; and
an instrument insertion feature disposed at the proximal end;

inserting a rod through the screw tower and into the head of the screw;
securing a locking cap to the screw through the screw tower; and
breaking the first half and the second half apart at the breakpoint and removing them from the incision
wherein the feature set includes a partial diameter truncated by two larger radii that extend to a height to form a tapered or conical surface at the distal end.

11. The screw tower of claim 10 , wherein each chevron is configured to flex out via a relief cut.

12. The screw tower of claim 10 , wherein each of the first half and the second half contain one of the plurality of chevrons.

13. The screw tower of claim 10 , wherein the distal end is laterally trimmed to reduce the profile of the tower.

14. The screw tower of claim 10 , wherein the first half and the second half form a rod slot.

15. The screw tower of claim 14 , wherein a diameter of the distal end is greater than a diameter of the proximal end.

16. The screw tower of claim 14 , wherein the size of the rod slot is greater than a screw head rod slot of the screw.

17. The screw tower of claim 10 , wherein the first half and second half are manufactured as a single piece configured to break apart at the breakpoint.

18. The screw tower of claim 10 , wherein the first half and the second half are welded together at or near the breakpoint.

Assignees

• Globus Medical Inc

Inventors

• Morris Ross

Classifications

• 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

• A61B17/7085 Primary

  for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis · CPC title

• A61B17/708

  with tubular extensions coaxially mounted on the bone anchors · CPC title

• A61B17/7086

  Rod reducers, i.e. devices providing a mechanical advantage to allow a user to force a rod into or onto an anchor head other than by means of a rod-to-bone anchor locking element; rod removers · CPC title

• A61B2090/037

  with a frangible part, e.g. by reduced diameter · CPC title