Augmented reality in knee arthroplasty: a scoping review of the current evidence

Background: Augmented reality (AR) is a promising tool in orthopedic surgery, particularly in total knee arthroplasty (TKA). AR enables real-time visualization of anatomical structures and surgical plans, enhancing intraoperative precision. However, significant knowledge gaps remain regarding patient-reported outcome measures (PROMs), standardized protocols, and long-term follow-up. This review aims to evaluate current evidence on the effectiveness and limitations of AR in TKA. Methods: A scoping review of English written preclinical and clinical studies published between January 2013 and October 2023 was conducted on PubMed, Scopus, Web of Science, and Google Scholar databases. Eligible studies were in English and reported on AR-assisted TKA systems. Sources included peer-reviewed journals and conference proceedings. Studies with unclear methodology or insufficient comparative data were excluded. Results: The review included five preclinical and six clinical studies. Preclinical studies demonstrated the high precision of AR systems, with tibial cut errors averaging 0.66° [standard deviation (SD) ±0.55°] in the coronal plane and 0.89° (SD ±0.75°) in the sagittal plane. Similarly, femoral cuts exhibited average errors of 1.1° (SD ±0.8°) in the coronal plane and 0.86° (SD ±0.5°) in the sagittal plane. Clinical studies confirmed the non-inferiority of AR systems compared to accelerometer-based navigation, with success rates of alignment within 3° of the mechanical axes reaching 95.4% for AR systems versus 93.2% for accelerometer navigation. Additionally, AR systems showed minimal impact on operative time and blood loss. However, significant heterogeneity in study designs and the lack of standardized PROMs were noted, limiting broader applicability and analysis. Conclusions: AR technology shows promise in improving surgical precision and reducing variability in TKA. However, challenges such as study heterogeneity, and the lack of standardized protocols and long- term outcomes limit its adoption. Future research should focus on standardized methods, patient-centered outcomes, and cost-effectiveness to support broader clinical use.