A new fixator for spine was designed to restore the stability of spine in improving the treatment of thoraco-lumbar dislocation. This instrument was composed of six nails, two longitudinal connecting rods and two transverse connecting rods. On the surface of the nails, there were furrows engraved, instead of screw thread. It fixed the spine through pedicle of vertebra from the posterior approach. The fixed vertebrae were limited between two vertebrae. From 1989 th 1995, twelve patients with fracture-dislocation of thoraco-lumbar spine were reduced with this instrument. After four years follow-up, it showed that the deformity was corrected and the spine firmly fixed. Compared with Dick’s screws, it had the following advantages such as simple manipulation, increased strergth of nails and minimal damage to tissue during operation.