Spinal implant with deployable and retractable barbs
The present invention provides spinal implants and systems which may be used for fixing a portion of the spine, such as the cervical spine, to allow correction or healing. One such spinal implant includes a body having at least one cavity therein. A barb is disposed within the cavity, with the barb adapted to rotate about a support member between a retracted position and a deployed position. In this manner, the barb may be selectively moved between desired positions, including the retracted and deployed positions. The retracted position may be used during insertion, removal, or repositioning of the implant between two vertebral bodies. The deployed barb position may be used for encouraging the barbs to engage the vertebral bodies to provide additional stability, promote fusion between the implant and vertebral bodies, hold the implant relative to the vertebral bodies, and the like.
1 . A spinal implant, comprising:
a body having at least one cavity therein; and
a barb disposed within the cavity, the barb adapted to rotate about a support member from a retracted position to a deployed position, and from the deployed position to the retracted position.
2 . The spinal implant as in claim 1 wherein the support member extends through the cavity to provide an axis of rotation for the barb.
3 . The spinal implant as in claim 1 wherein the barb rotates through at least about forty-five degrees (45°) of rotation between the retracted and deployed positions.
4 . The spinal implant as in claim 1 wherein the barb rotates through about ninety degrees (90) of rotation between the retracted and deployed positions.
5 . The spinal implant as in claim 1 wherein the body has spaced apart first and second surfaces, the first surface having the cavity formed therein, and wherein the barb is disposed below the first surface when in the retracted position.
6 . The spinal implant as in claim 1 further comprising a deployment device adapted to engage the barb within the body to cause the barb to rotate into the deployed position.
7 . The spinal implant as in claim 6 wherein the deployment device comprises an elongate member that is received by a channel within the body, the channel in communication with the cavity.
8 . The spinal implant as in claim 6 wherein the deployment device is removably coupled to the body to hold the barb in the deployed position.
9 . The spinal implant as in claim 6 wherein the deployment device is disposed within the body to be generally orthogonal to the support member.
10 . The spinal implant as in claim 6 wherein the deployment device is disposed within the body at an angle relative to the support member.
11 . The spinal implant as in claim 1 wherein removal of the deployment device from the body allows the barb to rotate from the deployed position towards the retracted position.
12 . The spinal implant as in claim 1 wherein the barb comprises a barb body having a rounded outer edge and a pointed end.
13 . The spinal implant as in claim 12 wherein the barb body is substantially C-shaped.
14 . The spinal implant as in claim 1 wherein the barb comprises a barb body and a tapered tip.
15 . The spinal implant as in claim 14 wherein the tapered tip is pyramidal in shape.
16 . The spinal implant as in claim 14 wherein the tapered tip is a blade tip.
17 . The spinal implant as in claim 14 wherein the barb body comprises a hole adapted to receive the support member.
18 . The spinal implant as in claim 1 wherein the barb is adapted to engage a vertebral body when in the deployed position.
19 . The spinal implant as in claim 1 wherein the barb is one of a plurality of barbs and the cavity is one of a plurality of cavities.
20 . The spinal implant as in claim 19 wherein the plurality of barbs are adapted to rotate in a same direction when rotated from the deployed position to the retracted position.
21 . The spinal implant as in claim 19 wherein the plurality of barbs are adapted to rotate in opposite directions when rotated from the deployed position to the retracted position.
22 . The spinal implant as in claim 1 wherein the body further comprises an opening passing at least part way therethrough, the opening adapted to receive a spinal implant placement instrument.
23 . The spinal implant as in claim 1 wherein the body further comprises a hole passing therethrough, the hole adapted to receive a fixation element for coupling the body to a vertebral body.
24 . A spinal implant, comprising:
a body having at least one cavity therein;
a plurality of barbs, at least one of the plurality of barbs disposed within the at least one cavity; and
a deployment member adapted to engage at least one of the plurality of barbs to move the barb from a retracted position to a deployed position;
wherein the plurality of barbs move in a same direction when moved from the retracted position to the deployed position.
25 . A spinal implant, comprising:
a first body adapted to be disposed adjacent a first vertebral body, the first body having at least one aperture therein with a first barb disposed within the aperture, the first barb adapted to rotate about a support member;
a second body adapted to be disposed adjacent a second vertebral body; and
a nucleus member disposed between the first and second bodies.
26 . The spinal implant as in claim 25 wherein the first and second bodies are adapted to be coupled to opposing first and second vertebral bodies in a disc space.
27 . The spinal implant as in claim 25 wherein the nucleus is adapted to allow relative movement between the first and second bodies.
28 . The spinal implant as in claim 25 wherein a barb deployment device is removably coupled to the first body to rotate the first barb between a retracted position and a deployed position.
29 . The spinal implant as in claim 28 wherein the barb deployment device is disposed within the first body to be generally orthogonal to the support member.
30 . The spinal implant as in claim 28 wherein the barb deployment device is disposed within the first body oriented at an acute angle relative to the support member.
31 . The spinal implant as in claim 28 wherein removal of the barb deployment device from the first body allows the first barb to rotate from the deployed position towards the retracted position.
32 . The spinal implant as in claim 25 wherein the second body further comprises at least one aperture having a second barb disposed therein, the second barb adapted to rotate about a second support member.
33 . The spinal implant as in claim 25 wherein the first body has spaced apart first and second surfaces, the first surface having the aperture formed therein, and wherein the first barb is disposed within the first body below the first surface when the first barb is in a retracted position.
34 . The spinal implant as in claim 33 wherein an axis of rotation of the first barb is below the first surface.
35 . The spinal implant as in claim 25 wherein the first barb comprises a substantially C-shaped barb body having a rounded outer edge and a pointed end.
36 . A spinal implant, comprising:
a first body adapted to be disposed adjacent a first vertebral body, the first body having at least one aperture therein with a first barb disposed within the aperture, the first barb adapted to move relative to the aperture to engage the first vertebral body;
a second body adapted to be disposed adjacent a second vertebral body; and
means for articulating the first and second bodies.
37 . The spinal implant as in claim 36 wherein the means for articulating the first and second bodies comprises a first articulation surface of the first body, the first articulation surface in at least partial contact with a second articulation surface of the second body.
38 . The spinal implant as in claim 36 wherein the means for articulating the first and second bodies comprises a ball and trough relationship of a portion of the first and second bodies.
39 . The spinal implant as in claim 36 wherein the means for articulating the first and second bodies includes an intermediate member that is positioned between the first body and the second body.
40 . A method of using a spinal implant, the method comprising:
providing a spinal implant comprising a first body having at least one cavity therein, and a barb disposed within the cavity, wherein the barb is adapted to rotate about a support member from a retracted position to a deployed position, and from the deployed position to the retracted position;
inserting the spinal implant between two vertebral bodies; and
rotating the barb about the support member to cause the barb to engage one of the vertebral bodies.
41 . The method as in claim 40 wherein the rotating of the barb comprises inserting a deployment device into the spinal implant first body, the deployment device engaging a barb body to rotate the barb from the retracted position to the deployed position.
42 . The method as in claim 41 further comprising fixing the barb in the deployed position by coupling the deployment device to the spinal implant first body.
43 . The method as in claim 40 further comprising retracting the spinal implant, wherein retracting the spinal implant causes the barb to rotate about the support member.
44 . The method as in claim 43 wherein retracting the spinal implant causes the barb to rotate from the deployed position to the retracted position.
45 . The method as in claim 43 wherein retracting the spinal implant comprises applying a translational force to the implant body, the translational force applying a rotational force to the barb.
46 . The method as in claim 40 wherein the spinal implant further comprises a second body and a nucleus member disposed between the spinal implant first and second bodies.
47 . The method as in claim 40 wherein the spinal implant further comprises a second body in articulating relationship with the first body.