Reduction in radiation (Fluoroscopy ) while maintaining safe placement of pedicle screws during lumbar spine fusion

Objective: The purpose of this study is to report the results using PediGuard (electrical conductivity device) to reduce radiation exposure while drilling the pilot hole for pedicle screw placement. Method: Eighteen patients diagnosed with a degenerative lumbar spine, that required a posterior spinal fusion. Average age of the patients were 55 ± 12 years. Patients received postoperative CT scans of all screws. Scans were reviewed by an independent reviewer grading 'in' < 2 mm of breach , or 'out' > 2 mm of breach. In a randomized fashion, the surgeon created pilot holes with either his standard technique or by using the PediGuard. Fluoroscopy was used for each drilling as necessary. Once the pilot hole was created, the surgeon inserted titanium screws into the pedicle pilot holes. A total of 78 screws (39 standard probe and 39 PediGuard ) were analyzed. Results: 78 screws (39 standard probe and 39 PediGuard were analyzed. No significant difference in breach rate > 2mm by either method (p=1.000), with one screw out in each group. Fluoroscopy shots averaged 5.2 (range, 0 to 15), average decrease of 2.3 (30%) per screw in the PediGuard group vs. 7.5 (range, 2 to 17) in the standard group (p<.001). Conclusion: This trial to assess pedicle probe location within the pedicle and vertebral body showed the number of fluoroscopy shots were reduced by 30%, compared to a standard probe while maintaining a 97.5% screw placement accuracy.