Abstract

Background: Transpedicular fixation is useful to resolve various degenerative and traumatic diseases of the thoracolumbar spine. Minimally Invasive Percutaneous Transpedicular Fixation (MIPTF) is preferred by many spine surgeons for its advantages related to less tissue damage, however, a constant concern of surgeons is the precision in percutaneous screw placement. The purpose of the study is to illustrate the utility of performing preoperative tomographic planning by analyzing the morphometric characteristics of each individual vertebra to increase the accuracy of thoracolumbar percutaneous transpedicular screw placement.
Methods: Preoperative Computed Tomography (CT) of 96 patients with MIPTF between April 2016 and December 2024 were included. 34 patients with traumatic disease and 62 patients with degenerative disease. In all cases, a postoperative tomography was obtained to verify the location of the screws. OsiriX DICOM Viewer program was used to perform the analysis of each fixed vertebra. No Intraoperative Neurophysiological Monitoring (INM) was used. We used conventional C-arm fluoroscopy.
Result: 438 screws were placed by two experienced surgeons at four medical centers. 433 (98.85%) screws with intrapedicular position and 5 (1.14%) screws with extrapedicular position showing eruption of the cortical vertebral body and external cortical pedicle that involved less than 50% of its diameter in the five cases. The positioning accuracy was graded using the Gertzbein and Robbins classification.
Conclusion: Performing preoperative morphometric analysis with CT prior to thoracolumbar percutaneous transpedicular fixation is an acceptable conduct to increase fixation accuracy in absence of INM.

Keywords:Planning CT pedicle screw; Percutaneous transpedicular fixation