A method includes a first member that connects to an intervertebral space between two adjacent vertebrae. The first member includes a pair of curved side walls connected to each of a front wall, an upper curved wall, and a lower curved wall, wherein a length of a first curved side wall is less than a length of each of a second curved side wall, the upper curved wall, and the lower curved wall, and wherein an edge of the second curved side wall is offset from an edge of the front wall. A second member is slidably attached to the first member, and includes a top and bottom curved wall each connected to an inclined side wall and a guide wall, wherein the guide wall includes grooves, wherein the second curved side wall of the first member slides in the grooves of the guide wall.
