Patent ID: 8353959

Claim:
An interbody spinal fusion implant for surgical implantation at least in part within a disc space between two adjacent vertebral bodies in a segment of a human spine, said implant comprising: a leading end for entry into the spine, a trailing end opposite said leading end, a length from said leading end to said trailing end, a maximum width perpendicular to the length, and upper and lower exterior surfaces for contacting each of the adjacent vertebral bodies when positioned therein, said implant having a vertical plane passing through said upper and lower surfaces and passing through said leading and trailing ends, the vertical plane bisecting the maximum width of said implant, said trailing end of said implant having a maximum height from said lower surface to said upper surface, the maximum height being perpendicular to both the length and the maximum width of said implant, the maximum height of said trailing end of said implant being adapted to fit into an implantation site created in the spine, each of said upper and lower surfaces having at least one opening adapted to communicate with one of the adjacent vertebral bodies, said openings in said upper and lower surfaces being in communication with one another and adapted to permit for the growth of bone from adjacent vertebral body to adjacent vertebral body through said implant, said trailing end having four bone screw receiving holes, each of said bone screw receiving holes having a central longitudinal axis passing through said trailing end and one of said upper and lower surfaces, each of said bone screw receiving holes having a diameter and being threaded to receive a complementary thread of a self-locking bone screw, two of said four bone screw receiving holes being on a left side of the vertical plane, another two of said four bone screw receiving holes being on a right side of the vertical plane, the central longitudinal axes of two of said four bone screw receiving holes closest to the vertical plane passing through one of said upper and lower surfaces of said implant so that respective bone screws inserted through said bone screw receiving holes closest to the vertical plane will both engage a first of the adjacent vertebral bodies, the central longitudinal axes of two of said four bone screw receiving holes furthest away from the vertical plane passing through the other of said upper and lower surfaces of said implant so that respective bone screws inserted through said bone screw receiving holes furthest away from the vertical plane will both engage a second of the adjacent vertebral bodies, said two of said four bone screw receiving holes closest to the vertical plane being separated by a distance less than the diameter of one of said two of said four bone screw receiving holes closest to the vertical plane.