A spinal implant for insertion into and positioning in an intervertebral space is provided. The spinal implant includes an intervertebral cage having at least two cage ends and a spacer for insertion into the intervertebral cage between the at least two cage ends, the spacer configured to distract the intervertebral space to a desired height. The intervertebral cage and spacer comprise bone, and in some embodiments, allograft bone. A method for fusing two adjacent vertebrae utilizing the intervertebral allograft cage and spacer is also provided.
