Real-Time Navigation with Guide Template for Pedicle Screw Placement Using an Augmented Reality Head-Mounted Device: A Proof-of-Concept Study.

Abstract

This study aims to explore the real-time navigation with guide template using an augmented reality head-mounted device (ARHMD) for pedicle screw placement. The spatial coordinate relationships between augmented reality images and real objects were established through the custom-made guide template, and the registration and tracking were completed using an ARHMD. The feasibility and accuracy of this method were verified by pedicle screw placement in 2 lumbar models. According to the Gertzbein-Robbins grading scale, the accuracy of pedicle screw placement was assessed. The navigation errors were estimated by measuring the deviation values of entry point and trajectory angle. A total of 20 pedicle K-wires were placed into L1-L5 in 2 lumbar models, which were successfully completed, with an average time of 11.5 min per model and 69 s per screw. The overall K-wires placement accuracy was 100% (20 screws). The navigation error was 2.77 ± 0.82 mm for the deviation value of entry point, and 3.03° ± 0.94° for the deviation value of trajectory angle. The application of an ARHMD combined with guide template for pedicle screw placement is a promising navigation approach.