Free-hand placement of high thoracic pedicle screws with the aid of fluoroscopy: evaluation of positioning by CT scans in a four-year consecutive series.

OBJECTIVE To evaluate the feasibility, safety and accuracy of pedicle screw placement in the upper thoracic spine using the free-hand technique with the aid of fluoroscopy; to analyze the methods used to verify correct screw positioning intra and postoperatively. METHOD All patients with instability of the cervicothoracic or upper thoracic spine and at least one screw placed in the segment T1-T6 as part of a posterior construct entered the study. Only C-arm intraoperative fluoroscopy was used to guide screw placement. RESULTS We obtained excellent positioning in 98.07% of the screws. CT scans precisely demonstrated pedicle wall and anterolateral body violations. There was no hardware failure, no neurological or vascular injury and no loss of alignment during the follow-up period. CONCLUSION Pedicle screws can be safely placed in the upper thoracic spine when strict technical principles are followed. Only a CT scan can precisely demonstrate vertebral body and medial pedicle cortical violations.