EXPANDING CAGE FOR VERTEBRAL SURGERY

• US 20100234956A1
• Filed: 03/25/2008
• Published: 09/16/2010
• Est. Priority Date: 03/28/2007
• Status: Active Grant

• Current Assignee: Francisco Ros Guillen, Gerald Schaumburg
• Original Assignee: Francisco Ros Guillen, Gerald Schaumburg
• Inventors: Ros Guillen, Francisco, Attia, David
• Granted Patent: US 8,491,657 B2
• Time in Patent Office: Days
• US Class Current: 623/17.160
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30369 Limited lateral translation of the protrusion within a larger recess
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30892 parallel
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

Abstract

The disclosure relates to an expanding device intended to be implanted between the vertebral end-plates of two adjacent vertebrae, in particular for a stabilisation operation for intervertebral fusion. The inventive device comprises: a cage forming a peripheral part that surrounds a central cavity, said peripheral part being formed by a leading edge and a thicker manipulation edge which are connected by two lateral edges provided with lateral housings; and a retractor received in the lateral housings, which can be moved between an insertion position, in which it is located close to the manipulation edge, and a locking position, in which it is located at the leading edge, increasing the height of same. The invention is characterised in that the retractor is provided with abutment means designed to maintain the retractor in the locking position and to oppose the release of the retractor from the cage.

Claims

1. An expanding device intended to be implanted between the vertebral bodies of two adjacent vertebrae, more particularly for an operation of stabilisation for an intervertebral fusion the device comprising:

a cage composing a peripheral part surrounding a central cavity, with the peripheral part being composed of a leading edge and a thicker handling edge, connected by two side edges provided with side holes; and

a retractor received in the side holes, with the retractor being able to be moved between an insertion position, wherein it is close to the handling edge and a locking position wherein it is at the level of the leading edge, the height of which it increases;

the retractor being provided with a stop adapted for maintaining the retractor in its locking position and for opposing the expulsion of the retracter from the cage.

2. An expanding device according to claim 1, wherein the stop opposes the side expulsion of the retractor.

3. An expanding device according to claim 1, wherein the stop opposes the expulsion of the retracter through the leading edge.

4. An expanding device according to claim 1, wherein the leading edge includes a hole for receiving the retracter, so as to cause the height of the leading edge in the locking position to increase.

5. An expanding device according to claim 1, wherein the side holes are slots provided along the side edges and the retracter is a rod, the ends of which are adapted to be inserted into the slots forming the side holes, the dimensions of the ends of the rod being greater than the thickness of the slots, so that the rod causes an expansion, by a resilient deformation, of the thickness of the device at the level of the rod.

6. An expanding device according to claim 5, wherein the leading edge includes a slot extending the slots forming the side holes, the slot being adapted to receive the retracter so as to cause the expansion of the leading edge.

7. A device according to claim 4, wherein the hole of the leading edge is of an area having a greater height in the slot of the leading edge.

8. A device according to claim 5, wherein the slots forming the side holes have a decreasing height between the handling edge and the leading edge.

9. A device according to claim 5, wherein the stop is lateral and positioned at the ends of the rod engaged in the slots forming the side holes, the ends being provided with side stops having a greater diameter forming a side-blocker.

10. A device according to claim 1, wherein the retracter includes two parts, the part which is on the handling edge side is higher than the part which is on the leading edge side, so that the part which is on the handling edge side abuts against the leading edge, opposing the expulsion of the retracter through the leading edge.

11. A device according to claim 10, wherein the part of the retracter which is on the handling edge side is comprised within the side edges.

12. A device according to claim 1, wherein the retracter includes a part included between the side edges and having a T-shaped section, with the foot of the T cooperating with the walls of the slots of the leading edge, and the bar of the T abutting against the leading edge.

13. A device according to claim 12, wherein the part of the retracter which is on the leading edge side has a length equal to that of the leading edge, so that the part which is on the leading edge side supports the leading edge on the whole length thereof when the retracter is in the locking position.

14. A device according to claim 13, wherein the handling edge and the leading edge are longer than the side edges.

15. A device according to claim 1, wherein the side edges are curved.

16. A device according to claim 1, wherein the side edges are formed so that the posterior lordosis of the device is substantially equal to 4°

, when the retracter is in the locking position.

17. A device according to claim 15, wherein the side edges substantially extend rectilinearly from the handling edge and then are curved towards the leading edge.

18. A device according to claim 1, wherein the leading edge and the side edges include two upper and lower U-shaped lugs connected to the handling edge and facing each other, thus defining the slot of the leading edge and the side holes between them.

19. A device according to claim 18, wherein the upper lug includes an upper convex wall for the interface with an upper vertebral body, the lower lug including a concave lower wall for the interface with a lower vertebral body.

20. A device according to claim 1, wherein the cage is made in one solid piece.

21. A device according to claim 1, wherein the cage is made of polyetheretherketone.

22. A device according to claim 1, wherein the retracter is made in one solid piece.

23. A surgical method for positioning, by anterior route, an expanding device for the substitution of an intervertebral disc between two cervical vertebrae, the method comprising:

retraction of two cervical vertebrae;

removal of the intervertebral disc;

insertion of the expanding device through the leading edge thereof between the two vertebrae, with a retracter of the expanding device being in its insertion position, so that the expanding device occupies the whole surface initially occupied by the operated intervertebral disc;

positioning of the retracter in the locking position thereof.