Abstract: An artificial spine for use in an expansion of a vertebral canal which comprises an intermediate section having a pair of contacting surfaces in both ends thereof, the contacting surfaces being disposed along each outer end of a pair of divided spines; an inner side section extending from the intermediate section to between said pair of divided spines and having a width, in a horizontal cross-section thereof, which is gradually reduced in the direction of the vertebral canal; and an outer side section extending from the intermediate section to a side opposed to said inner side section, the outer side section being disposed out of the divided spaces; and at least a surface portion of the artificial spine being formed from a biocompatible ceramic material. The artificial spine has an excellent compatibility with the divided spines, and can be easily fixed to the divided spines, without hindering movement of a cervical spine.