ROD REDUCTION DEVICE AND METHOD OF USE

• US 20180303516A1
• Filed: 06/28/2018
• Published: 10/25/2018
• Est. Priority Date: 07/13/2007
• Status: Active Grant

• Current Assignee: K2M, Inc (Stryker Corporation)
• Original Assignee: K2M, Inc (Stryker Corporation)
• Inventors: Barrus, Michael, Jones, Scott
• Granted Patent: US 10,292,736 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 17/7001 Screws or hooks combined with longitudinal elements which do not contact vertebrae A61B17/7058 takes precedence
• CPC Class Codes: A61B 17/7086 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 Class Codes: A61B 17/7089 wherein insertion is along an arcuate path
• CPC Class Codes: A61B 17/88 Osteosynthesis instruments; Methods or means for implanting or extracting internal or external fixation devices A61B17/7074 takes precedence
• CPC Class Codes: A61B 17/8872 Instruments for putting said fixation devices against or away from the bone A61B17/7074, A61B17/808 take precedence
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 2017/00407 Ratchet means

Abstract

Provided is a novel rod reducing device including a screw jack mechanism that is moveably engaged with an elongated grasping fork assembly, the screw jack mechanism having an elongated threaded portion, the elongated threaded portion being connected at its most distal end to a rod contact member, which is positioned in sliding circumferential contact with each of the two opposing elongated grasping members and the most proximal end of the elongated threaded portion terminating in a controlling member, which can be activated in a measured and controlled manner. A method of using the device is also provided.

Claims

1. (canceled)

2. A rod reducing device comprising:

a fork assembly body defining a longitudinal axis and having a passage extending therethrough along the longitudinal axis thereof, the passage including internal threads;

a first arm extending from a first side of the fork assembly body;

a second arm extending from a second side of the fork assembly body, the second side different from the first side, the first and second arms configured to grasp a portion of a bone anchor therebetween; and

an elongated threaded screw shaft having external threads thereon and rotatably coupled with the internal threads of the passage, wherein a rod contact member at a distal portion of the elongated threaded screw shaft is configured to engage a rod, the distal portion of the elongated threaded screw shaft and the rod contact member movable between the first and second arms in response to engagement of the threads of the elongated threaded screw shaft with the threads of the passage.

3. The rod reducing device of claim 2, wherein the first and second arms are transitionable between a non-parallel arrangement and a parallel arrangement, the parallel arrangement configured to grasp a portion of a bone anchor.

4. The rod reducing device of claim 3, wherein the parallel arrangement of the first and second arms defines a first distance between distal portions of the first and second arms, and wherein the non-parallel arrangement of the first and second arms defines a second distance between the distal portions of the first and second arms which is greater than the first distance.

5. The rod reducing device of claim 2, wherein a distal portion of the first arm includes a first protrusion and a distal portion of the second arm includes a second protrusion, the first and second protrusions extending towards each other and configured to grasp a portion of a bone anchor therebetween.

6. The rod reducing device of claim 2, wherein rotation of the elongated threaded screw shaft in threaded engagement with the threads of the passage causes the rod contact member to move distally along the longitudinal axis of the fork assembly body to contact a rod and urge the rod disposed between the first and second arms towards distal ends of the first and second arms.

7. The rod reducing device of claim 2, wherein rotation of the elongated threaded screw shaft in threaded engagement with the threads of the passage causes the rod contact member to move distally towards distal ends of the first and second arms.

8. The rod reducing device of claim 2, wherein the rod contact member defines through passages configured for movement along the first and second arms.

9. The rod reducing device of claim 2, wherein distal movement of the rod contact member urges the rod contact member into contact with a rod disposed between the first and second arms to urge the rod towards distal ends of the first and second arms.

10. The rod reducing device of claim 2, wherein the distal portion of the elongated threaded screw shaft and the rod contact member move in a plane defined by the first and second arms to contact the rod.

11. The rod reducing device of claim 2, wherein the first and second arms extend distally from the fork assembly body.

12. The rod reducing device of claim 2, wherein the rod contact member is connected to the distal portion of the elongated threaded screw shaft and the elongated threaded screw shaft being rotatable relative to the rod contact member.

13. The rod reducing device of claim 2, wherein a longitudinal axis of the elongated threaded screw shaft is coincident with the longitudinal axis of the fork assembly body.

14. The rod reducing device of claim 2, wherein the distal portion of the elongated threaded screw shaft is coincident with the longitudinal axis of the fork assembly body.

15. The rod reducing device of claim 2, where the distal portion of the elongated threaded screw shaft and the rod contact member move along the longitudinal axis of the elongated threaded screw shaft between the first and second arms to urge the rod towards distal ends of the first and second arms.

16. The rod reducing device of claim 2, wherein the fork assembly body is unitary.

17. The rod reducing device of claim 8, further including camming surfaces located on the first and second arms.

18. The rod reducing device of claim 2, wherein rotation of the elongated threaded screw shaft in threaded engagement with the threads of the passage moves the distal portion of the elongated threaded screw shaft such that at least some of the threads of the elongated threaded screw shaft are visible between the first and second arms.