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

Prospective, randomized, controlled study. To report the results of using the PediGuard (SpineGuard, Inc., San Francisco, CA), a local electrical conductivity measurement device, to reduce radiation exposure while drilling the pilot hole for pedicle screw placement. Reports of pedicle screw placement in the lumbar spine have shown medial pedicle perforations with nerve root impingement in addition to lateral pedicle and vertebral body perforations that can impinge the nerve root within the psoas. Routine use of fluoroscopy (fluoro) is thought to reduce the risk of perforations but is associated with increased radiation. A new pedicle-drilling device (PediGuard) which uses electrical conductivity differentiation at the tip for assessing bone versus soft tissue, has been developed to improve the safe positioning of pedicle screws. This device not only warns of an impending medial breach but also is the only device available to, in real time, nonradiographically detect a lateral breach. METHODS.: Eighteen patients with a diagnosis of lumbar degenerative spine who had a posterior spinal fusion were enrolled. The average age of the patients was 55 ± 12 years. Postoperative computed tomographic scans were reviewed by an independent reviewer. Screws were considered "in" (