Interbody spinal fusion implant having a trailing end with at least one stabilization element
View Patent ↗A flanged interbody spinal fusion implant for insertion at least in part between adjacent vertebral bodies has opposed upper and lower surfaces adapted to contact each of the adjacent vertebral bodies from within the disc space, a leading end for insertion between the adjacent vertebral bodies, and a trailing end opposite the leading end. The trailing end has a height greater than the maximum height of the disc space forming a flanged portion adapted to overlie a part of the anterior aspects of the vertebral bodies adjacent and proximate the disc space to be fused. The flanged portion has at least two bone screw receiving holes, at least one each adapted to overlie each of the adjacent vertebral bodies at least in part. The implant has at least one locking element to lock one or more of the bone screws inserted in the bone screw receiving holes. Instrumentation for inserting the implant, forming screw holes in the vertebral body, and for locking the locking elements are disclosed.
1. An interbody spinal implant for insertion at least in part between two vertebral bodies adjacent a disc space to be fused, said implant comprising:
a maximum width that is greater than one-half of the width of the adjacent vertebral bodies into which said implant is adapted to be inserted;
opposed upper and lower surfaces adapted to contact each of the adjacent vertebral bodies, respectively, from within the disc space, each of said upper and lower surfaces including an opening having a maximum width greater than one-half the maximum width of said implant;
a leading end for insertion between the adjacent vertebral bodies, a trailing end opposite said leading end and a mid-longitudinal axis through said leading and trailing ends, said trailing end including an upper stabilization element and a lower stabilization element, said upper stabilization element forming the upper-most portion of said trailing end, said lower stabilization element forming the lower-most portion of said trailing end;
opposite sides between said trailing and leading ends, each of said opposite sides including an exterior surface having a non-curved portion in a plane parallel to the mid-longitudinal axis of said implant;
two bone screw receiving holes extending through said trailing end, each of said bone screw receiving holes being adapted to receive a bone screw for engaging said implant to one of the adjacent vertebral bodies; and
a locking element configured to lock two of the bone screws, each of the bone screws being adapted to be inserted in a respective one of said two bone screw receiving holes, each of said bone screw receiving holes being adapted to receive one of the two bone screws, said locking element being configured to be coupled to said implant prior to the insertion of the two bone screws into one each of said two bone screw receiving holes, said locking element being moveable from an initial position that permits the insertion of at least one of the two bone screws into a respective one of said bone screw receiving holes to a final position that is adapted to retain the two bone screws to said implant.
2. The implant of claim 1 , wherein each of said opposite sides includes an interior surface forming a portion of each of said openings, said interior surface of each of said opposite sides including a non-curved portion in the plane parallel to the mid-longitudinal axis of said implant.
3. The implant of claim 1 , wherein said openings of said upper and lower surfaces are in communication with one another to define a generally open interior of said implant.
4. The implant of claim 1 , wherein said two bone screw receiving holes each have a central longitudinal axis, the central longitudinal axes of said bone screw receiving holes each being at an angle relative to the mid-longitudinal axis of said implant to position bone screws in a convergent relationship to one another.
5. The implant of claim 1 , wherein said two bone screw receiving holes each have a central longitudinal axis, the central longitudinal axes of said bone screw receiving holes each being at an angle relative to the mid-longitudinal axis of said implant to position bone screws in a divergent relationship to one another.
6. The implant of claim 1 , further comprising at least one bone screw having a leading end for placement in the vertebral body and a trailing end opposite said leading end adapted to cooperatively engage said implant so as to prevent the further advancement of the screw into the bone and to be retained within one of said bone screw receiving holes of said implant.
7. The implant of claim 1 , wherein said implant comprises at least one of the following materials: metal, titanium, plastic, and ceramic.
8. The implant of claim 1 , in combination with a bone growth promoting material.
9. The implant of claim 1 , in combination with an insertion instrument adapted to cooperatively engage at least a portion of said implant.
10. The implant of claim 1 , said leading end extends continuously from one of said opposite sides to another of said opposite sides.