Robotic spine systems: overcoming surgeon experience in pedicle screw accuracy: a prospective study.

Study design: Prospective single-center study.

Purpose: To compare the accuracy of pedicle screws placed by freehand and under fluoroscopy and robotic assistance with intraoperative image acquisition.

Overview of literature: Pedicle screws are the most commonly used spinal anchors owing to their ability to stabilize all three spinal columns. Various techniques such as freehand, fluoroscopy-assisted, and navigation-assisted pedicle screw placements have been used with varying degrees of accuracy. Most studies on robotic-assisted pedicle screw placement have utilized preoperatively acquired computed tomography scans. To our knowledge, this is the only study in the literature that compared freehand with fluoroscopy-guided and robotic-assisted pedicle screw insertion with freehand and fluoroscopy.

Methods: In this prospective study, a total of 1,120 pedicle screws were placed in the freehand group (n=175), 1,250 in the fluoroscopyassisted group (n=172), and 1,225 in the robotic-assisted group (n=180). Surgical parameters and screw accuracy were analyzed between the three groups. The preoperative plan overlapped with the postoperative O-arm scan to determine if the screws were executed as planned.

Results: The frequency of clinically acceptable screw placement (Gertzbein-Robbins grades A and B) in the freehand, fluoroscopy-assisted, and robotic-assisted groups were 97.7%, 98.6%, and 99.34%, respectively. With robotic assistance, an experience-neutralizing effect implied that surgeons with varying levels of experience achieved comparable pedicle screw accuracy, blood loss, O-arm time, robot time, and time per screw. No significant difference in these parameters was found between surgeries commencing before and after 2 PM. No significant differences were noted between the planned and executed screw trajectories in the robotic-assisted group irrespective of surgical experience.

Conclusions: The third-generation robotic-assisted pedicle screw placement system used in conjunction with intraoperative threedimensional O-arm imaging consistently demonstrates safe and accurate screw placement with an experience-neutralizing effect.