Introduction:  In spine surgery, screw guidance techniques continue to to improve safety and accuracy while providing minimally invasive options and improved outcomes.  Augmented reality (AR) is a novel technology to assist in screw placement and has shown promising results in early cadaveric and feasibility studies.  This study aims to contribute an initial experience to the limited in vivo studies available by demonstrating safety and accuracy in the largest cohort of patients to date using ahead-mounted device (HMD) AR system.

Methods:  Consecutive adult patients undergoing AR-assisted thoracolumbar fusion surgery between 2020-2021 with a minimum of 2 week follow-up were included in this multi-surgeon, single center prospective cohort study.  Preoperative, intraoperative, and postoperative data were collected to include demographics, complications, revision surgeries, and AR performance.  Intraoperative 3D imaging was used to assess screw accuracy using the Gertzbein and Robbins (G-R) grading scale.

Results:  32 patients (40.6% male) were included giving a total of 222 screws executed with the FDA approved HMD-AR system.  Intraoperatively, 4 (1.8%) were deemed misplaced, and replaced freehand.  The remaining 218 (98.2%) screws were placed accurately, there were no intraoperative adverse events or complications, and AR was not abandoned.   Of the 208 AR-placed screws with 3D imaging intraoperatively, 97.1% were considered clinically accurate (91.8% Grade A, 5.3% Grade B).  There were no postoperative surgical complications or revision surgeries during the 2 week follow-up.

Discussion:  This early experience study demonstrated that HMD-AR assisted spine surgery is a safe and accurate method of placing pedicle, cortical, and pelvic fixation.  An accuracy rate of 97.1% among all 3 surgeons novice to AR technology suggests ease of integration into the surgical workflow and minimal learning curve.  Larger studies are needed to continue support this compelling evolution in spine surgery.