Laterally expandable cage

[Solution means] The piece (100) of a backbone transplant extensible in a transverse direction includes two wings (104) currently made so that it may enter in the inner side chamber formed in the central body (102) and the central body. The wing has a guide rail (302) which 嵌合 into the slot (304) demarcated by the central body. In order to certainly fix the piece of a transplant surely, each guide rail has the outside end equipped with the cut side (406) deeply cut to a 椎骨 end plate, when expanding a wing. Both wings are connected to one by the central turn buckle shaft (108) by which the screw which has a gear tooth and carries out engaging of clutch to the cave with a screw in a wing to both ends was turned off. A turn buckle shaft can be rotated and a transverse direction can be made to elongate a wing from a central component with a gear tooth now. In order to prevent a wing retreating, the 係止 mechanism (120) is 係止 (ing) the turn buckle shaft.