The present disclosure provides an intervertebral cage having an upper member and a lower member each including a mating surface for mating with a corresponding vertebra. The intervertebral cage also includes a posterior member that extends between the posterior ends of the upper and lower members and separates them vertically from one another. The upper member and the lower member extend from the rear member in the front-rear direction, and define a front free end, and an end substantially opening in the rear-front direction between the upper member and the lower member Form. The fitting surfaces of the upper member and the lower member are branched from each other in the vertical direction along the rear front direction. Each of the upper and lower members includes a first opening extending therethrough in a vertical direction, the opening defining a path through the intervertebral cage in the vertical direction.本発明の開示は、相当する椎骨と嵌合させる嵌合面をそれぞれ含む上位部材及び下位部材をもつ椎間ケージを提供するものである。椎間ケージは後方部材をも含み、前記後方部材は、上位及び下位部材の後方端部の間で延長し、そして、それらを互いに上下方向に隔てる。上位部材及び下位部材は、後方部材から後前方向に延長し、そして、前方自由端部を規定して、前記上位部材と前記下位部材との間で後前方向に実質的に開口する端部を形成する。上位部材及び下位部材の嵌合面は、後前方向に沿って上下方向に互いに分岐する。上位部材及び下位部材の各々は、それらを通って上下方向に延長する第一開口部を含み、前記開口部は、上下方向に前記椎間ケージを通過する経路を規定する。
