One-step Minimally Invasive Pedicle Screw Instrumentation Using O-Arm and Stealth Navigation

Abstract

Study Design: Description of a navigated, single-step, minimally invasive technique for the placement of pedicle screws. Objective: To describe a new technique for minimally invasive placement of pedicle screws in the lumbar spine using O-arm and StealthStation navigation in combination. Summary of Background Data: Minimally invasive surgical techniques are described in the literature as safe and effective methods for pedicle screw instrumentation. These techniques increase radiation exposure and prompt multiple instrument passes through the pedicle. Materials and Methods: In total, 35 adult patients (187 screws) underwent lumbar surgery with pedicle screw placement using the 1- (8 patients/48 screws) or 2-step (27 patients/139 screws) technique. Complications associated with instrumentation were noted. Pedicle screw position was evaluated. Results: Of 187 screws placed, 181 (96.8%) were found to be fully contained within the pedicle (grade 1) and 4 (2.1%) had a breach of <2 mm. In the 1-step technique, no screws were malpositioned. One screw at S1 with inadequate fixation was replaced with a screw 1 mm larger in diameter. In the 2-step technique, 2 screws (1.06% overall) were revised due to inferior breach of the pedicle. No neurological sequelae were noted. Also, 1 screw was deemed too long at S1 and was replaced with a shorter screw. None of the revised pedicle screws caused neuromonitoring changes and the breaches were found intraoperatively on 3D imaging. Conclusions: Using O-arm and StealthStation navigation with minimally invasive surgical technology for placement of posterior spinal instrumentation is safe, effective, and limits radiation exposure.