Non-pedicle based interspinous spacer
Spinal distraction apparatus includes at least one plate member having upper and lower surfaces adapted for placement between opposing upper and lower spinous processes having outer lateral surfaces. A pair of scissoring elements are hingedly affixed to the plate member to engage with the lateral surfaces of the spinous processes. A device is provided for locking the scissoring elements in position once a desired degree of contact is made. In a preferred configuration, the scissoring elements are sandwiched between a pair of opposing plate members, each having upper and lower surfaces adapted for placement between opposing upper and lower spinous processes, and the inner surfaces of the scissoring elements are concave. The device for locking the scissoring elements in position is a fastener that extends through a central portion of both scissoring elements and the plate members. The apparatus may further include a retractor with upper and lower plates for spreading the upper and lower spinous processes apart to receive the plate with scissoring element(s), and wherein the upper and lower surfaces of the plate member have notches to accommodate the upper and lower plates.
1. A spinal stabilization device, comprising:
a plate member configured to be placed between an upper spinous process and a lower spinous process, the plate member having an upper surface configured to abut a lower surface of the upper spinous process and a lower surface configured to abut an upper surface of the lower spinous process;
a pair of scissoring elements coupled to the plate member, each scissoring element being rotatable relative to the plate member, each scissoring element including an upper end that rotates to extend beyond the upper surface of the plate member and a lower end that rotates to extend beyond the lower surface of the plate member, such that inner surfaces of the upper ends of the scissoring elements rotate into contact with opposing outer lateral surfaces of the upper spinous process and inner surfaces of the lower ends of the scissoring elements rotate into contact with opposing outer lateral surfaces of the lower spinous process, wherein the upper ends of the scissoring elements are configured to avoid extending into the upper spinous process and the lower ends of the scissoring elements are configured to avoid extending into the lower spinous process; and
a locking device configured to secure the scissoring elements in a fixed position, the locking device configured to lock the spinal stabilization device between the upper and lower spinous processes upon rotation of the scissoring elements into contact with the outer lateral surfaces of the upper spinous process and the lower spinous process such that the upper spinous process and the lower spinous process are stabilized by the spinal stabilization device.
2. The spinal stabilization device of claim 1 , wherein the inner surfaces of the upper ends and lower ends of the scissoring elements are concave.
3. The spinal stabilization device of claim 1 , wherein the locking device is a fastener that extends through the plate member and a central portion of both scissoring elements.
4. The spinal stabilization device of claim 1 , wherein the plate member comprises a first plate member, and wherein the stabilization device further comprises:
a second plate member positioned substantially parallel to the first plate member and configured to be placed between the upper spinous process and the lower spinous process, the second plate member having an upper surface configured to abut a lower surface of the upper spinous process and a lower surface configured to abut an upper surface of the lower spinous process; and
wherein the scissoring elements are rotatable relative to and positioned between the first plate members and the second plate member.
5. The spinal stabilization device of claim 1 , further including:
a retractor for spreading the upper and lower spinous processes apart to a position in which to receive the plate member.
6. The spinal stabilization device of claim 1 , further including:
a retractor with upper and lower plates for spreading the upper and lower spinous processes apart to receive the plate member; and
wherein the upper and lower surfaces of the plate member have notches to accommodate the upper and lower plates of the retractor.
7. The spinal stabilization device of claim 1 , wherein the plate member further comprises first and second lateral surfaces each extending between the upper surface and lower surface,
wherein the spinal stabilization device is configured such that, prior to rotation of the scissoring elements, the upper end of each scissoring element extends laterally beyond the first lateral surface and the lower end of each scissoring element extends laterally beyond the second lateral surface.
8. The spinal stabilization device of claim 1 , wherein the inner surfaces of the upper ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the upper spinous process and the inner surfaces of the lower ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the lower spinous process.
9. The spinal stabilization device of claim 1 , wherein the upper ends of the scissoring elements are configured to contact the outer lateral surfaces of the upper spinous process in a substantially contiguous manner and the lower ends of the scissoring elements are configured to contact the outer lateral surfaces of the lower spinous process in a substantially contiguous manner.
10. A spinal stabilization device, comprising:
a plate member configured to be positioned between an upper spinous process and a lower spinous process, the plate member having a superior surface configured to abut a lower surface of the upper spinous process and an inferior surface configured to abut an upper surface of the lower spinous process;
a pair of scissoring elements coupled to the plate member, each scissoring element being rotatable relative to the plate member, each scissoring element including an upper end and a lower end, the upper end configured to rotate from an insertion configuration in which the upper end extends beyond a first outermost lateral surface of the plate member to a stabilization configuration in which the upper end extends beyond the upper surface of the plate member to contact a lateral surface of a first spinous process, the lower end configured to rotate from the insertion configuration in which the lower end extends beyond a second outermost lateral surface of the plate member to a stabilization configuration in which the lower end extends beyond the lower surface of the plate member, and wherein, when in the stabilization configuration, the upper ends of the scissoring elements contact opposing outer lateral surfaces of the upper spinous process and the lower ends of the scissoring elements contact with opposing outer lateral surfaces of the lower spinous process such that the upper spinous process and the lower spinous process are stabilized by the spinal stabilization device; and
a locking device configured to secure the scissoring elements in the stabilization configuration.
11. The spinal stabilization device of claim 10 , wherein the inner surfaces of the upper ends and the lower ends of the scissoring elements are configured to contact the outer lateral surfaces of the spinous processes in a substantially contiguous manner along a length of the outer lateral surfaces.
12. The spinal stabilization device of claim 10 , wherein the inner surfaces of the upper ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the upper spinous process and the inner surfaces of the lower ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the lower spinous process.
13. The spinal stabilization device of claim 10 , wherein the plate member comprises a first plate member, and wherein the interspinous process spacer further comprises:
a second plate member positioned substantially parallel to the first plate member and configured to be positioned between the upper spinous process and the lower spinous process, the second plate member having a superior surface configured to abut a lower surface of the upper spinous process and an inferior surface configured to abut an upper surface of the lower spinous process; and
wherein the scissoring elements are disposed between and rotatable relative to the first and second plate members.
14. The spinal stabilization device of claim 10 , wherein the locking device comprises a fastener that extends through the plate member and a central portion of both scissoring elements.
15. The spinal stabilization device of claim 10 , further comprising:
a retractor with upper and lower plates for spreading the upper and lower spinous processes apart to receive the plate member with scissoring elements; and
wherein the superior and inferior surfaces of the plate member have notches to accommodate the upper and lower plates of the retractor.
16. A spinal stabilization device, comprising:
a plate member configured to be placed between an upper spinous process and a lower spinous process, the plate member having an upper surface configured to abut a lower surface of the upper spinous process and a lower surface configured to abut an upper surface of the lower spinous process;
a pair of scissoring elements coupled to the plate member, each scissoring element being rotatable relative to the plate member, each scissoring element including an upper end that rotates to extend beyond the upper surface of the plate member and a lower end that rotates to extend beyond the lower surface of the plate member, such that inner surfaces of the upper ends of the scissoring elements rotate into substantially contiguous contact with opposing outer lateral surfaces of the upper spinous process and inner surfaces of the lower ends of the scissoring elements rotate into substantially contiguous contact with opposing outer lateral surfaces of the lower spinous process; and
a locking device configured to secure the scissoring elements in a fixed position, the locking device configured to lock the spinal stabilization device between the upper and lower spinous processes upon rotation of the scissoring elements into contact with the outer lateral surfaces of the upper spinous process and the lower spinous process such that the upper spinous process and the lower spinous process are stabilized by the spinal stabilization device.
17. The spinal stabilization device of claim 16 , wherein the inner surfaces of the upper ends and lower ends of the scissoring elements are concave.
18. The spinal stabilization device of claim 16 , wherein the plate member comprises a first plate member, and wherein the stabilization device further comprises:
a second plate member positioned substantially parallel to the first plate member and configured to be placed between the upper spinous process and the lower spinous process, the second plate member having an upper surface configured to abut a lower surface of the upper spinous process and a lower surface configured to abut an upper surface of the lower spinous process; and
wherein the scissoring elements are rotatable relative to and positioned between the first plate members and the second plate member.
19. The spinal stabilization device of claim 16 , wherein the upper ends of the scissoring elements are configured to avoid extending into the upper spinous process and the lower ends of the scissoring elements are configured to avoid extending into the lower spinous process.
20. The spinal stabilization device of claim 16 , wherein the inner surfaces of the upper ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the upper spinous process and the inner surfaces of the lower ends of the scissoring elements are configured to substantially conform to the outer lateral surfaces of the lower spinous process.