Application of augmented reality in orthopedic surgery

Purpose— Augmented Reality (AR) is a novel cutting-edge technology that is increasingly being employed by various surgical fields for navigation, including orthopedic surgery. In our pre-clinical studies, we implemented AR in two key domains of orthopedic surgery, i.e., orthopedic oncology and total hip arthroplasty (THA), for surgical guidance and to assess its accuracy and feasibility. Methods— For revision total hip arthroplasty (rTHA), an AR-guided system was developed for the reaming of large acetabular defects, with the goal of enhancing the precision of custom implant placement on a patient-specific phantom. This technique was evaluated against conventional approaches (freehand and patient-specific instrumentation (PSI)) to determine comparative accuracy. Accuracy was evaluated in terms of achieved inclination and anteversion against planned angulation, as well as deviation across the x, y, and z axes. For orthopedic oncology, we explored the application of AR in tumor resection, aiming to facilitate negative-margin excisions and reduce recurrence risk. Accuracy was assessed using cutting guides with different grooves (1 mm, 2 mm, and 3 mm) to evaluate achieved osteotomy lines. The study utilized advanced AR head-mounted displays (AR-HMDs), namely Microsoft HoloLens 2 and Magic Leap 2, and conducted comparative analyses to evaluate their respective performance and accuracy. Results— In revision hip arthroplasty, AR guidance and PSI-assisted reaming demonstrated superior accuracy compared to the conventional freehand method. Both PSI and AR-assisted techniques achieved absolute errors of less than 3° in post-implantation inclination and anteversion, whereas the freehand method exhibited errors exceeding 3°. Deviations along the x, y, and z axes were not statistically significant. For AR-assisted osteotomies, the Magic Leap 2 outperformed the HoloLens 2 and showed better ergonomic performance. Conclusions— AR demonstrates promising accuracy in revision THA and oncologic resections, with Magic Leap 2 showing superior overall performance.