Effects of Augmented Reality on Thoracolumbar Pedicle Screw Instrumentation Across Different Levels of Surgical Experience

Abstract

Objective Augmented reality (AR) is an emerging technology that may accelerate skill acquisition and improve accuracy of thoracolumbar pedicle screw placements. We quantify the relative assistance of AR compared to free-hand (FH) pedicle screw accuracy across different surgical experience levels. Methods A spine fellowship-trained and board-certified attending neurosurgeon, PGY-4 neurosurgery resident, and 2nd year medical student placed a total of 32 FH and 32 AR-assisted thoracolumbar pedicle screws in 3 cadavers. A cableless, voice activated AR system (VisAR, Novarad, Provo, UT) was paired with a HoloLens 2 headset (Microsoft Corp., Redmond, WA). Accuracy was assessed using Chi-square analysis and the Gertzbein-Robins scale (GRS). Angular error, distance error, and time per pedicle screw were also collected and compared. Results The attending had 91.6% (11/12) clinically acceptable (GSR A or B) in both FH and AR groups; the resident had 100% (9/9) FH and AR in both cases; the medical student had 72.3% (8/11) FH accuracy and 81.8% (9/11) AR accuracy. The medical student had significantly lower ideal (GRS A) FH accuracy compared to the resident (p = 0.017) and attending (p= 0.005), but no difference when using AR. FH screw placement was faster by both the attending (median 46s vs. 94.5s, p=0.0047) and resident (median 144s vs. 140s, p=0.05). Total clinically acceptable AR and FH accuracy was 90.6% (29/32) and 87.5% (28/32, p = 0.69), respectively. Conclusion AR screw placement allowed an inexperienced medical student to double his accuracy in one training session. With subsequent iterations, this promising technology could serve as an important tool for surgical training.