Spinal and other implants may be bone or synthetic material shaped as rings, C-shaped or rectangular and so on and also may have serrated wedge shaped top and bottom surfaces to match the disc space lordosis of adjacent ertebra and so on. The implants have one or more recesses aligned in an insertion...http://www.google.ca/patents/US20030083747?utm_source=gb-gplus-sharePatent US20030083747 - Bone implant and isertion tools
