Patent ID: 7942933

Claim:
An interbody spinal fusion implant for insertion across the surgically corrected height of a disc space between two adjacent vertebral bodies of a human spine, said implant comprising: a leading end for insertion first into the disc space, a trailing end opposite said leading end, a length between said ends, and a mid-longitudinal axis passing through said leading and trailing ends, said leading end including an exterior surface being arcuate in both a first plane and a second plane adjacent the intersection of the mid-longitudinal axis therewith, said first plane and said second plane extending along the mid-longitudinal axis and being perpendicular to one another; opposed upper and lower portions adapted to contact the adjacent vertebral bodies when implanted in the spine, said opposed upper and lower portions of said implant including at least one opening in communication with one another for permitting for the growth of bone from vertebral body to vertebral body through said implant; and non-threaded bone engaging projections for engaging said implant to the adjacent vertebral bodies, said bone engaging projections extending from at least a portion of said opposed upper and lower portions, at least two of said bone engaging projections being formed as a frusto-conical segment, each of said frusto-conical segments having a forward-facing facet directed at least in part toward said leading end, each of said forward-facing facets having a slope, the slope of at least one of said forward-facing facets being different from the slope of another of said forward-facing facets of said frusto-conical segments.