Evaluation of the effectiveness of intraoperative fluoroscopy and postoperative computed tomography in thoracolumbar fusion surgeries

Objective: This study aims to evaluate the accuracy and safety of pedicle screw placement in thoracolumbar spinal fusion surgeries. comparing intraoperative two-way fluoroscopy and postoperative computed tomography (CT), and to analyze the influence of spinal anatomy and biomechanics. Materials and methods: A retrospective cohort study was conducted on 94 patients who underwent thoracolumbar spinal fusion surgery. Demographic data including age, gender, and surgical indications were collected. Intraoperative fluoroscopy and postoperative CT images were analyzed to assess pedicle screw placement accuracy. Results: Among the 519 pedicle screws placed, 496 (95.6%) were graded as A or B in the intraoperative fluoroscopy, whereas 23 (4.4%) were C, D, or E. Postoperative CT findings demonstrated a significant difference (p<0.001) in screw placement accuracy, with 483 (93.1%) screws rated as A or B. Moreover, the postoperative CT showed a higher precision in determining the screws’ alignment with vertebral bodies, stability, and potential complications. The correlation between intraoperative and postoperative imaging modalities indicated substantial sensitivity (93.8%), specificity (95.6%), positive predictive value (98.8%), and negative predictive value (83.3%). Conclusion: Postoperative CT emerges as a crucial imaging method in enhancing the success and safety of pedicle screw placement in spinal fusion surgeries.