The use of virtual reality to assess the bony landmarks at the knee joint - The role of imaging modality and the assessor's experience.

Background: At present, extended reality technologies such as virtual reality (VR) have gained popularity in orthopedic surgery. The first aim of this study was to assess the precision of VR and other imaging modalities - computed tomography (CT), magnetic resonance imaging (MRI) - to localize bony landmarks near the knee joint. Secondly, the impact of the educational level of the assessor - medical master students, orthopedic residents, and orthopedic surgeons - on the precision with which landmarks near the knee joint could be localized was analyzed.

Methods: We included a total of 77 participants: 62 medical master students, 10 orthopedic residents, and 5 orthopedic surgeons to analyze three cadaver legs. Every participant localized a series of sixteen bony landmarks on six different imaging modalities (CT, MRI, 3D-CT, 3D-MRI, VR-CT, VR-MRI).

Results: Concerning the imaging modality, the inter- and intra-observer variability were lowest for 3D and VR, higher for MRI (respectively 7.6 mm and 6.9 mm), and highest for CT (respectively 9 mm and 8.7 m).Concerning the educational level of the assessor, inter- and intra-observer variability in VR were lowest for surgeons, (respectively 3.2 mm and 3.6 mm), higher for residents (respectively 5.9 mm and 6.5 mm) and medical students (respectively 5.9 mm and 5.8 mm).

Conclusions: VR can be considered a reliable imaging technique. Localization of landmarks tends to be more precise in VR and on 3D than on conventional CT and MRI images. Furthermore, orthopedic surgeons localize landmarks more precisely than orthopedic residents and medical students in VR.