Surgical fixation assembly and methods of use

Patent metadata

Field	Value
Publication number	US-11317958-B2
Application number	US-201816498965-A
Country	US
Kind code	B2
Filing date	Mar 22, 2018
Priority date	Mar 30, 2017
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

A fixation assembly includes a tapered cannula, a post, and a snap ring. The snap ring is attachable to the post and the tapered cannula. The snap ring is configured to maintain the tapered cannula axially fixed in relation to the post such that the tapered cannula and the post are rotatable relative to each other.

First claim

The invention claimed is:

1. A fixation assembly, comprising:
a tapered cannula;
a post defining a tapered distal tip and a shank having a non-threaded outer surface; and
a snap ring attachable to the post and the tapered cannula, the snap ring configured to maintain the tapered cannula axially fixed in relation to the post such that the tapered cannula and the post are rotatable relative to each other,
wherein when the post and the tapered cannula are axially fixed relative to one another, the tapered distal tip and at least a portion of the shank extend distally beyond a distal end of the tapered cannula.

2. The fixation assembly of claim 1 , wherein the tapered cannula is threaded.

3. The fixation assembly of claim 1 , wherein the post defines a first ring groove positioned to receive the snap ring therein.

4. The fixation assembly of claim 3 , wherein the tapered cannula defines a second ring groove positioned to receive the snap ring therein.

5. The fixation assembly of claim 1 , wherein the snap ring is formed of a flexible material.

6. The fixation assembly of claim 1 , wherein the post supports a ledge configured to engage the tapered cannula to limit distal movement of the post relative to the tapered cannula.

7. The fixation assembly of claim 1 , wherein the tapered cannula defines at least one cut out in a proximal end portion thereof.

8. The fixation assembly of claim 1 , wherein the post includes a spherical head supported on a proximal end portion thereof.

9. The fixation assembly of claim 1 , wherein the shank defines an elliptical cross-section.

10. The fixation assembly of claim 9 , wherein the tapered distal tip has at least one flat surface to facilitate insertion of the shank into osseous tissue.

11. A fixation assembly comprising:
a rod-receiving housing; and
a fixation assembly coupled to the rod-receiving housing, the fixation assembly including:
a tapered cannula;
a post including a tapered distal tip and a shank defining an elliptical cross-section and a non-threaded outer surface; and
a snap ring attachable to the post and the tapered cannula to secure the post and the tapered cannula together.

12. The fixation system of claim 11 , wherein the tapered cannula is threaded.

13. The fixation assembly of claim 11 , wherein the post defines a first ring groove positioned to receive the snap ring therein.

14. The fixation assembly of claim 13 , wherein the tapered cannula defines a second ring groove positioned to receive the snap ring therein.

15. The fixation assembly of claim 11 , wherein the snap ring is formed of a flexible material.

16. The fixation assembly of claim 11 , wherein the post supports a ledge configured to engage the tapered cannula to limit distal movement of the post relative to the tapered cannula.

17. The fixation assembly of claim 11 , wherein the tapered cannula defines at least one cut out in a proximal end portion thereof.

18. The fixation assembly of claim 11 , wherein the post includes a spherical head supported on a proximal end portion thereof.

19. A method for securing a fixation assembly to osseous tissue, the method comprising:
securing a tapered cannula to an isthmus of a pedicle;
pushing a post through the tapered cannula and the isthmus of the pedicle, the post defining a tapered distal tip and a shank having a non-threaded outer surface; and
axially fixing the post to the tapered cannula with a snap ring such that the tapered distal tip and at least a portion of the shank extend distally beyond a distal end of the tapered cannula.

Assignees

• K2M Inc

Inventors

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

Classifications

• A61B17/7035

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

• A61B17/864

  hollow, e.g. with socket or cannulated · CPC title

• A61B17/7082

  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

• A61B17/8625

  Shanks, i.e. parts contacting bone tissue · CPC title

• A61B17/00

  Surgical instruments, devices or methods (A61B18/00 takes precedence; dental tools A61C3/00; eye surgery A61F9/007; ear surgery A61F11/20) · CPC title