Patent ID: 8617246

Claim:
An interbody spine fusion cage for promoting fusion between adjacent bone structures, comprising: a cage body having a posterior end and an anterior end and an outer surface extending longitudinally therebetween, the cage body defining an internal cavity and having a plurality of apertures extending through the outer surface in communication with the internal cavity, the outer surface comprising a preselected pattern of perforated and non-perforated areas and having a plurality of threads extending therearound; and first and second non-perforated end closures at the posterior end and the anterior end of said cage body, respectively, wherein at least one of the end closures has a longitudinally extending occluding surface that is -rotatable relative to the cage body so as to selectively occlude at least one of the plurality of apertures from providing access to the internal cavity, and wherein a distance from the first end closure to the second end closure is configured to remain constant during rotation of the longitudinally extending occluding surface, wherein, upon implantation, a perforated area in contact with an adjacent bone structure is configured to allow bone growth therethrough while a perforated area not in contact with adjacent bone structure is occluded by the longitudinally extending occluding surface of the end closure.