Modular screw

Patent metadata

Field	Value
Publication number	US-11298156-B2
Application number	US-201816498812-A
Country	US
Kind code	B2
Filing date	Mar 28, 2018
Priority date	Mar 30, 2017
Publication date	Apr 12, 2022
Grant date	Apr 12, 2022

Abstract

A modular screw includes a post and a head assembly. The post includes a tapered portion extending along a length of the post, the post defining a first bore. The head assembly is adjustably coupled with the post. The head assembly includes a head defining a slot configured to receive a spinal rod therein, an elongate screw having external threads extending along a length of the elongate screw, and a screw shank defining a second bore configured to receive the elongate screw therein. The screw shank includes an engaging portion configured to expand radially outward when the elongate screw engages the engaging portion, and internal threads configured to engage the external threads of the elongate screw. At least a portion of the screw shank is dimensioned to be selectively received in the first bore of the post.

First claim

What is claimed is:

1. A modular screw comprising:
a post including a tapered portion extending along a portion of a length of the post, the post defining a first bore; and
a head assembly adjustably coupled with the post, the head assembly including:
a head defining a slot configured to receive a spinal rod therein;
an elongate screw having external threads extending along a portion of a length of the elongate screw; and
a screw shank defining a second bore defining internal threads configured to engage the external threads of the elongate screw when the elongate screw is received within the second bore of the screw shank, the screw shank including a shaft having a keyed outer surface including a longitudinal ridge and an engaging portion provided with a gripping surface, the engaging portion configured to expand radially outward when the elongate screw engages the engaging portion,
wherein at least a portion of the screw shank is dimensioned to be selectively received in the first bore of the post.

2. The modular screw according to claim 1 , wherein the engaging portion of the screw shank defines slits to facilitate radial expansion of the engaging portion.

3. The modular screw according to claim 1 , wherein the engaging portion is axially spaced from the keyed outer surface along the shaft of the screw shank.

4. The modular screw according to claim 1 , wherein at least a quarter of the engaging portion has the gripping surface.

5. The modular screw according to claim 1 , wherein the gripping surface includes threads.

6. The modular screw according to claim 1 , wherein the first bore of the post and the screw shank have complementary cross-sections.

7. The modular screw according to claim 1 , wherein the screw shank includes a polyaxial head and the shaft extends distally from the polyaxial head.

8. The modular screw according to claim 7 , wherein the polyaxial head of the screw shank is operatively coupled with the head for polyaxial movement relative to the head.

9. The modular screw according to claim 7 , wherein the polyaxial head includes a bulbous shape.

10. The modular screw according to claim 1 , wherein the tapered portion of the post extends at least a quarter of a length of the post.

11. The modular screw according to claim 1 , wherein the tapered portion of the post extends at least a half of a length of the post.

12. The modular screw according to claim 1 , wherein the tapered portion of the post includes external threads.

13. The modular screw according to claim 1 , wherein a major diameter of the tapered portion of the post is in the range of about 10 mm and about 12 mm.

14. The modular screw according to claim 1 , wherein the external threads of the elongate screw of the head assembly are spaced from the distal end of the elongate screw and extend at least a sixteenth of a length of the elongate screw.

15. The modular screw according to claim 14 , wherein the external threads of the elongate screw of the head assembly extend at least an eighth of a length of the elongate screw.

16. The modular screw according to claim 15 , wherein the external threads of the elongate screw of the head assembly extend at least a quarter of a length of the elongate screw.

17. The modular screw according to claim 1 , wherein the elongate screw defines a cavity having a key feature for engagement with a driver to drive the elongate screw.

Assignees

• K2M Inc

Inventors

• Errico Thomas J
• Newton Peter
• Shufflebarger Harry
• Mcclintock Larry E

Classifications

• A61B17/8685

  comprising multiple separate parts · CPC title

• A61B17/7035 Primary

  Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other · CPC title

• A61B17/7037 Primary

  wherein pivoting is blocked when the rod is clamped · CPC title