Continued improvements in treatments of the thoracolumber spine have occured in the last several years. The operative treatment of choice currently is short segment fusion(instrumentation one level above to one level below the injury). The development of pedicle screw systems has brought short segment fusion into clinical reality from the posterior approach. We analysed the clinical results of 20 patients with unstable fracture and fracture-dislocation of thoracolumbar spine who were treated with the posterior transpedicular screw system. The mean fol- low-up was 18 month. Ll was the most common injury level and the bursting fracture was the most common fracure type by Denis classification. The mean preoperative sagital index was 21.5??and improved 8.1??postoperatively. The mean preoperative anterior and posterior height of the vertebral height were 56.9% and 88.8% and improved postoperatively 94.7 and 88.8 respectively. The mean preoperative neural canal impingement in neural defici: patient was 47.2% and was improved 30.65% postoperatively. The mean prooperative ASIA motor was 34.1 and improved 41.7 postoperatively. There was no metal failure. These data suggested that the posterior transpedicular screw fixation, transpedicle bone graft, decompression and posterolateral bone graft was able to porvide sufficient stability and to achieve the neurologic improvement.