Minimally Invasive, Stereotactic, Wireless, Percutaneous Pedicle Screw Placement in the Lumbar Spine: Accuracy Rates With 182 Consecutive Screws

Abstract

Background: Standard fluoroscopic navigation and stereotactic computed tomography-guided lumbar pedicle screw instrumentation traditionally relied on the placement of Kirshner wires (K-wires) to ensure accurate screw placement. The use of K-wires, however, is associated with a risk of morbidity due to potential ventral displacement into the retroperitoneum. We report our experience using a computer image-guided, wireless method for pedicle screw placement. We hypothesize that minimally invasive, wireless pedicle screw placement is as accurate and safe as the traditional technique using K-wires while decreasing operative time and avoiding potential complications associated with K-wires.Methods: We conducted a retrospective review of 42 consecutive patients who underwent a stereotactic-guided, wireless lumbar pedicle screw placement. All screws were placed to provide fixation to a variety of interbody fusion constructs including anterior lumbar interbody fusion, lateral interbody fusion, and transforaminal lumbar interbody fusion. The procedures were performed using the O-arm intraoperative imaging system with StealthStation navigation (Medtronic, Memphis, TN) and Medtronic navigated instrumentation. After placing a percutaneous navigation frame into the posterior superior iliac spine or onto an adjacent spinous process, an intraoperative O-arm image was obtained to allow subsequent StealthStation navigation. Para-median incisions were selected to allow precise percutaneous access to the target pedicles. The pedicles were cannulated using either a stereotactic drill or a novel awl-tipped tap along with a low-speed/high-torque power driver. The initial trajectory into the pedicle was recorded on the Medtronic StealthStation prior to removal of the drill or awl-tap, creating a ''virtual'' K-wire rather than inserting an actual Kwire to allow subsequent tapping and screw insertion. Accurate screw placement is achieved by following the virtual path as an exact computer-aided design model of the screw traversing the pedicle is projected onto the display and by using audible and tactile feedback. A second O-arm scan was obtained to confirm accuracy of screw placement.Results: A total of 20 women and 22 men (average age ¼ 56 years) underwent a total of 182 pedicle screw placements using the stereotactic, wireless technique. The total breach rate was 9.9%, with a clinically significant breach rate of 0% (defined as .2 mm medial breach or .4 mm lateral breach) and a clinical complication rate of 0%.Conclusions: Wireless, percutaneous placement of lumbar pedicle screws using computed tomography-guided stereotactic navigation is a safe, reproducible technique with very high accuracy rates. Minimally Invasive Surgery

A cadaveric precision and accuracy analysis of augmented reality–mediated percutaneous pedicle implant insertion

“…4). The present clinical accuracy rates compare favorably with literature reporting percutaneous pedicle screw insertion accuracy rates for manual computer-navigated methods (range 96%-100%), 6,7,[23][24][25][26][27][28]40 particularly for the lower reported thoracic insertion accuracies ranging from 75.6% to 94.9%, where the anatomical threshold for error is smaller. 6,25 The present results also compare favorably with robot-navigated percutaneous insertion, where reported clinical accuracy rates range widely from 89% to 100%, depending on the timing of publication and robot platform used.…”

Accuracy of Screw Placement and Fusion Rate after Transforaminal Lumbar Interbody Fusion with O-arm Navigation: A Review of 475 Patients

“…Van et al evaluated 1922 screws in an international, multicenter study and found 97.5% correct placements and 1.8% needing immediate revision. Sadrameli et al (2018) conducted wireless percutaneous pedicle screw placement for 182 screws and demonstrated 90.1% screw accuracy [22]. Higher than in previous reports, the present study showed 99.66% accuracy.…”

Workflow and Efficiency of Robotic-Assisted Navigation in Spine Surgery

“…At this point, percutaneous rods are placed and any indicated compressions, distractions, and/or reductions are performed. A second fluoroscopy scan is taken to confirm accurate screw placement prior to the tightening of locking caps [11]. Subsequently, a 3D fluoroscopy scan is taken as an additional confirmation of accuracy.…”