Interspinous stabilization and fusion device
An interspinous stabilization device configured to fit interlaminarly between adjacent vertebrae and their spinous processes, while also cooperating with a bone graft, or bone substitute, component to facilitate fusion at that segment of the spine is disclosed. Also provided is a method for using such a device and bone graft, or bone substitute, component to stabilize a spinal segment.
1. A spinal stabilization system, comprising:
an implantable device having a main body configured for interlaminar placement between adjacent vertebrae, the main body having a midsection, and an inferior section and superior section extending from the midsection to form a U-shaped body,
each of the inferior and superior sections having a length and a pair of lateral walls extending therefrom to form a stirrup for receiving a spinous process;
each of the lateral walls including an aperture for receiving a bone fastener;
each of the inferior and superior sections further having a U-shaped cutout portion to form a receiving slot, each of the receiving slots having three walls formed around an opening facing the posterior direction, and vertically extending teeth along the length of each wall of a pair of opposed walls to form a gripping surface within the receiving slot to prevent slippage in the posterior direction; and
a bone fastener for securing the implantable device to the spinous process.
2. The system of claim 1 , wherein the pair of lateral walls of the inferior section is not vertically aligned with the pair of lateral walls of the superior section.
3. The system of claim 1 , wherein the main body includes one or more horizontally extending ridges for enhancing bone attachment.
4. The system of claim 3 , wherein the one or more horizontally extending ridges are located on an external surface of the inferior and superior sections.
5. The system of claim 4 , wherein the one or more horizontally extending ridges of each of the inferior and superior sections extend at an angle toward the pair of lateral walls extending therefrom.
6. The system of claim 4 , wherein the one or more horizontally extending ridges are located on an interior surface of the lateral walls.
7. The system of claim 6 , wherein the one or more horizontally extending ridges extend around the apertures of the lateral walls.
8. The system of claim 1 , wherein the vertically extending teeth of the receiving slot of the superior section are vertically aligned with the vertically extending teeth of the receiving slot of the inferior section.
9. The system of claim 1 , wherein the vertically extending teeth are uniformly spaced apart.
10. The system of claim 1 , wherein the vertically extending teeth extend at an angle toward the midsection of the main body.
11. The system of claim 1 , wherein the vertically extending teeth are configured to enable ratcheting, adjustable depth placement of the fusion promoting component within the receiving slots.
12. The system of claim 1 , wherein each of the receiving slots is U-shaped.
13. The system of claim 1 , further including a bone fusion promoting component configured for placement inside each of the receiving slots.
14. The system of claim 1 , wherein each of the pair of lateral walls is movable relative to one another.
15. The system of claim 1 , wherein the superior section has a tapered free end.
16. The system of claim 1 , wherein the length of the inferior section is different than the length of the superior section.
17. The system of claim 16 , wherein the length of the inferior section is greater than the length of the superior section.