Granted Patent B2

US 8,956,361 · App. 13/720,525 · Granted Feb 17, 2015

Abstract

Claims (12)

1. A bone screw system comprising:

an elongate fixation element adapted to engage a bone and having a head portion and a threaded shank portion;

a receiving element defining an internal bore sized to receive the shank portion of the fixation element and a seat adapted to support the head portion of the fixation element, the receiving element comprising a pair of opposed legs separated by a rod receiving channel sized for complimentary engagement with a stabilizer rod, wherein the pair of opposed legs defines a compression element receiving chamber;

a coupling element configured to be positioned in the receiving element below the stabilizer rod, the coupling element having a top portion having a saddle shape to conform to the shape of the stabilizer rod, the coupling element providing additional surface area of contact between the stabilizer rod and the head portion of the fixation element;

a compression element configured to engage a portion of the receiving element and be complimentarily received in the compression element receiving chamber, the compression element configured to compress the stabilizer rod into the receiving element to fix the position of the stabilizer rod with respect to the receiving element;

a pair of leg extensions, each leg extension having a first end and a second end, wherein the second end extends away from and is coupled to the respective opposed leg of the receiving element, each leg extension having the same outer cross sectional shape as the leg to which it is coupled, the pair of leg extensions thereby defining an extension of the compression element receiving chamber, wherein the pair of leg extensions define a first insertion tool pathway therebetween and a second insertion tool pathway therebetween on opposing sides of the extension of the receiving chamber, and wherein the pair of leg extensions is coupled by a connector spanning the first insertion tool pathway positioned at a point or predetermined distance spaced from and in near proximity to the first end to provide a fulcrum point against which an insertion tool holding the stabilizer rod can use the connector as a fulcrum from which the insertion tool can rotate traversing both the first and second insertion tool pathways to allow the stabilizing rod and the insertion tool to pass to push the stabilizer rod into position within the receiving chamber, and wherein the second insertion tool pathway is open from the first end through the second end of the leg extensions to the rod receiving channel and wherein the leg extensions and the legs are integral, and wherein at a coupling point between the legs and leg extensions there is a reduced thickness.

2. The bone screw system of claim 1 , wherein the compression element is adapted to move downward into the compression element receiving chamber to force the stabilizer rod into contact with the coupling element and translate a force onto the head portion of the fixation element to substantially fix the position of the fixation element with respect to the receiving element.

3. The bone screw system of claim 1 , wherein the compression element comprises external threads and an interior portion of the opposed legs comprises internal threads complimentary to the external threads.

4. The bone screw system of claim 3 , wherein an interior portion of the leg extensions each have internal threads.

5. The bone screw system of claim 1 , wherein the compression element, the coupling element and the fixation element each define a coaxial guide wire aperture.

6. The bone screw system of claim 1 , wherein the leg extensions have a cross sectional shape and the opposed legs each have a cross-sectional shape, and wherein the cross-sectional shape of the leg extensions is substantially similar to the cross-sectional shape of the opposed legs.

7. The bone screw system of claim 1 , wherein the leg extensions are removably coupled to the respective legs at the coupling point.

Assignments (8)