Patent ID: 8840668

Claim:
A spinal fusion implant, comprising: a body configured for implantation between a superior and an inferior vertebra, having a top surface and a bottom surface, an anterior height and a posterior height, and a fusion aperture defined by an anterior wall, a posterior wall, and first and second lateral walls; a plurality of fastener apertures extending through the anterior wall at oblique angles relative to a horizontal axis, each of said fastener apertures dimensioned to receive a bone fastener for insertion into one of the superior or inferior vertebrae, said bone fastener having a head, a shank and a collar disposed between said head and said shank; wherein said plurality of fastener apertures have an anterior diameter and a posterior diameter, wherein said anterior diameter is greater than said posterior diameter; and wherein said plurality of fastener apertures each comprise an annular groove dimensioned to retain the head of the bone fastener therein and a washer disposed within the annular groove, wherein each of the fastener apertures further includes a visualization marker on an exterior facing surface of the fastener aperture proximally adjacent the annular groove, said visualization marker configured to be obscured by the bone fastener during insertion of the bone fastener into the body and wholly visible on the exterior-facing surface of the fastener aperture when the bone fastener is fully inserted into the body.