Dynamic stabilization system
A spinal stabilization system including an insert positionable in the channel of the housing of a vertebral anchor, and an associated support construct including a spacer and at least one cord extending through the insert. In some instances the construct includes first and second cords extending through first and second bores of the insert. A clamping member clamps the cord(s) in the insert. In some instances the clamping member includes first and second tabs movable in channels in first and second flanges of the insert.
1. A spinal stabilization system comprising:
an monolithic insert positionable to extend through a channel of a housing of a vertebral anchor, the insert comprising:
a first flange positionable on a first exterior side of the housing of the vertebral anchor;
a second flange positionable on a second exterior side of the housing of the vertebral anchor;
a medial portion extending between the first flange and the second flange along an insert longitudinal axis that is transverse to a channel longitudinal axis when positioned therein;
a first and a second bore extending through the insert parallel to the insert longitudinal axis; and
an opening disposed in and extending entirely through the medial portion to communicate with both the first and second bores; and
a support construct including first and second cords, the first and second cords positionable through the first and second bores of the insert such that the first and second bores surround the entire perimeter of portions of the first and second cords.
2. The spinal stabilization system of claim 1 , further comprising:
the vertebral anchor comprising the housing defining the channel; and
a fastener configured to rotatably engage the housing of the vertebral anchor, wherein rotational engagement of the fastener with the housing causes the fastener clamp both the first and second cords in the insert.
3. The spinal stabilization system of claim 2 , wherein the fastener directly contacts each of the first and second cords to exert a clamping force directly on the first and second cords.
4. The spinal stabilization system of claim 2 , wherein the fastener includes a threaded portion and a protuberance extending from the threaded portion, wherein the protuberance is extendable into the opening of the insert to contact each of the first and second cords.
5. The spinal stabilization system of claim 4 , wherein the opening extends perpendicular to the bore.
6. The spinal stabilization system of claim 2 , wherein rotational engagement of the fastener with the housing causes the fastener to clamp both the first and second cords in the insert and secure the insert in the housing of the vertebral anchor.
7. The spinal stabilization system of claim 6 , wherein the first bore extends parallel to and is offset from the second bore, and the opening extends perpendicular to and intersects the first and second bores.
8. The spinal stabilization system of claim 2 , wherein the vertebral anchor includes a threaded shaft extending from the housing, wherein the threaded shaft has a lumen extending therethrough for advancement over a K-wire.
9. The spinal stabilization system of claim 8 , wherein the opening extends entirely through the insert such that the insert is advanceable over the K-wire into the housing of the vertebral anchor with the K-wire positionable between the first and second cords.