Intraoperative 3-D imaging can improve accuracy of pedicle screw placement in spine surgery

“CT scans taken after surgery were compared to the findings of intraoperative BPR and 3D imaging to detect either false-positive or false-negative readings,” explained Fedan Avrumova, BS, an HSS clinical research coordinator who presented the study at the AAOS meeting. “False positive findings are instances when BPR imaging suggests the screw was not in an acceptable position, while in fact a more advanced 3D image (intraoperative 3D scan or postoperative CT scan) showed the screw to be in an acceptable position. Conversely, a false negative instance was when a BPR image led one to believe or looked as though the screw was in an acceptable position, when in fact a more advanced 3D image or post-operative CT scan showed that it was in fact not acceptable.”

Postoperative CT imaging revealed a clinically significant number of patients who had false-negative and false-positive screw placement readings on BPR. However, screw position shown on intraoperative 3D imaging was found to be much more accurate, Avrumova added.

“Based on our study, BPR imaging may lead one to think a screw is acceptable when in fact it is not, and also may miss many screws that are not in fact acceptable. In our study, it was approximately one percent of cases where this occurred. However, for surgeons and centers that implant hundreds and thousands of screws per year, this is going to result in a significant clinical impact for many people,” Dr. Lebl noted. “Even one misplaced screw can have a significant impact for a patient, a surgeon, and a hospital system. Therefore, based on these findings, we suggest that for intraoperative confirmation of screw position 3D imaging may soon represent a new standard of care.”