Background & Aims: Thuracolumbar Unstable Fractures (T, L.U.F) are common after spine truma. Posterior pedicular fixation is a technique that is use for fixation of these fractures. This study evaluates the accuracy of pedicular screw placement in T, LUF with the assistance of plain radiography in operation rooms.

  Materials & Methods: This study is a case-control and analytical study. 35 patients with T, LUF underwent fixation with 180 pedicle screws placement by s33 spinal system with the assistance of plain radiography and anatomic landmarks.

  Results: The first plain radiography shows that accuracy point and direction of 30 screws were unsuitable. In the second radiography, after correcting the entry point and direction, 10 screws had unsuitable position. In the third radiography, 3 screws had unsuitable but acceptable position.

  Conclusion: Plain radiography and recognition of spine anatomic landmarks are helpful in accuracy posterior pedicular screw placement.