Method for preparing a space in the human spine
View Patent ↗A method for use in a vertebral spine to prepare a space between adjacent vertebral bodies to receive an implant. The method is performed using a bone removal device including a shaft and a mounting member at one end of the shaft. A working end is mounted on the mounting member and is coupled to a drive mechanism adjacent to the working end. The drive mechanism is operable to move the upper and lower cutters of the working end to create surfaces having predetermined contours in the end plate region of the adjacent vertebral bodies. A guard provides protected access to the disc space and the adjacent vertebral bodies for the working end of the bone removal device through a passageway.
1. A method for preparing a space in the human spine to receive an implant between adjacent vertebral bodies, the method comprising:
providing a bone removal device including a shaft having a proximal end and a distal end opposite the proximal end, a mounting member disposed at the distal end of the shaft, a working end having a leading end adapted for insertion into the spine and a trailing end opposite the leading end, the working end mounted on the mounting member, the working end having at least two cutters, a drive mechanism operably connected to the trailing end of the working end for moving the cutters of the working end, and a power source operably connected to the drive mechanism;
activating the power source of the bone removal device to cause the drive mechanism to rotate the cutters;
contacting the cutters against the adjacent vertebral bodies to simultaneously remove bone from each of the adjacent vertebral bodies and create the space having a predetermined surface contour into each of the adjacent vertebral bodies as the cutters are moved into the adjacent vertebral bodies;
removing the cutters from the space created in the bone; and
inserting an implant into the space created in the bone, the implant having a shape corresponding to the predetermined surface contour of the space created in the bone.
2. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes forming the predetermined surface contour of the space to include surfaces that are generally parallel relative to one another.
3. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes forming the predetermined surface contour of the space to include surfaces that are angled relative to one another.
4. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes forming the predetermined surface contour of the space to include surfaces that are at least in part concave.
5. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes forming the predetermined surface contour of the space to include surfaces that are at least in part planar.
6. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes creating the space having opposed side walls, at least one of the side walls being at least in part straight.
7. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes creating the space having a curved leading portion and a trailing portion being shaped to generally match the natural curvature of the anterior aspect of the adjacent vertebral bodies.
8. The method of claim 7 , wherein the leading portion of the space has a first radius of curvature and the trailing portion of the space has a second radius of curvature greater than the first radius of curvature.
9. The method of claim 8 , wherein the inserting includes inserting an implant having a leading end with a radius of curvature generally matching the radius of curvature of the leading portion of the space.
10. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes creating the space having a maximum depth less than a maximum depth of each of the vertebral bodies.
11. The method of claim 1 , wherein the contacting of the cutters against the adjacent vertebral bodies includes creating the space having a maximum width being greater than one half of a maximum width of each of the adjacent vertebral bodies.
12. The method of claim 11 , wherein the inserting of the implant includes inserting an implant having a maximum width generally matching the maximum width of the space
13. The method of claim 1 , further comprising suctioning debris from the space created in the bone.
14. The method of claim 1 , further comprising irrigating the space created in the bone.
15. The method of claim 1 , wherein the cutters are rotated in different directions from one another.
16. The system of claim 1 , wherein the cutters are rotated about an axis generally perpendicular to a mid-longitudinal axis of the shaft.
17. The method of claim 1 , further comprising inserting a guard into the disc space between the adjacent vertebral bodies.
18. The system of claim 17 , wherein the inserting of the guard comprises inserting a guard including first and second disc penetrating extensions extending from the guard for insertion into the disc space between the adjacent vertebral bodies, each of the disc penetrating extensions having a portion for bearing against each of the adjacent vertebral bodies.
19. The system of claim 17 , wherein the inserting of the guard comprises inserting a guard including a foot plate sized and shaped to contact at least a portion of each of the adjacent vertebral bodies, the foot plate having at least one opening configured to receive a fastener adapted to secure the foot plate to the vertebral bodies.
20. A method for preparing a space in the human spine to receive an implant between adjacent vertebral bodies, the method comprising:
providing a bone removal device including a shaft having a proximal end and a distal end opposite the proximal end, a mounting member disposed at the distal end of the shaft, a working end having a leading end adapted for insertion into the spine and a trailing end opposite the leading end, the working end mounted on the mounting member, the working end having at least two cutters, a drive mechanism operably connected to the trailing end of the working end for moving the cutters of the working end, and a power source operably connected to the drive mechanism;
activating the power source of the bone removal device to cause the drive mechanism to rotate the cutters;
contacting the cutters against the adjacent vertebral bodies to remove bone therefrom and create the space having a predetermined surface contour into each of the adjacent vertebral bodies as the cutters are moved into the adjacent vertebral bodies, the space created having a maximum width less than one half of a maximum width of each of the adjacent vertebral bodies;
removing the cutters from the space created in the bone; and
inserting an implant into the space created in the bone, the implant having a shape corresponding to the predetermined surface contour of the space created in the bone.
21. The method of claim 20 , wherein the contacting of the cutters against the adjacent vertebral bodies includes creating the space having opposed side walls, at least one of the side walls being at least in part straight.
22. The method of claim 20 , wherein the cutters are rotated in different directions from one another.
23. The system of claim 20 , wherein the cutters are rotated about an axis generally perpendicular to a mid-longitudinal axis of the shaft.