Patent ID: 8579980

Claim:
An allograft intervertebral implant sized and configured for implantation between first and second adjacent vertebra via a transforaminal lumbar interbody fusion technique, the implant comprising: an allograft body formed from at least two pieces of allograft bone, the body including a curved front surface, a curved back surface, a pair of ends separating the curved front and back surfaces, an upper surface and a lower surface wherein the upper and lower surfaces are sized and configured for contacting at least a portion of the first and second vertebrae, the curved front and back surfaces defining an outer perimeter of the implant; wherein the first allograft bone piece has a first interface surface comprising a recess defining a first portion of at least one dovetail joint, wherein the second allograft bone piece has a second interface surface comprising a projection defining a second portion of the at least one dovetail joint, and wherein the recess has an opening and a rear and is sized and configured to receive the projection and the at least two pieces of allograft bone are joined together by the at least one dovetail joint, wherein the recess and the projection are sized and configured to achieve a press-fit type connection when the projection is slidably received in the recess thereby providing resistance against separation of the first and second allograft bone pieces, and wherein the recess becomes more narrow towards the rear of the recess such that the at least one dovetail joint becomes tighter once the projection is fully inserted into the recess.