Navigation of Tumor and Metastatic Lesions in the Thoracolumbar Spine

Since the description of transpedicle fixation of posterior spinal implants by Roy-Camille et al. [18], this procedure has gained general acceptance for rigid segmental fixation. Correct implantation of the screws without perforation of the pedicle is difficult and requires detailed anatomic knowledge and good surgical skills. The identification of the correct entry point for the pedicle screw and the correct angle of inclination in the sagittal and transverse planes are crucial. A standard technique for pedicle screw insertion is done with an image intensifier in the lateral and anteroposterior (a.p.) views. In osteolytic tumors identification of anatomical landmarks is difficult and intraoperative imaging can be impossible due to increased radio translucent vertebrae.