Citation: Innocente, C.; Ulrich, L.;
Moos, S.; Vezzetti, E. Augmented
Reality: Mapping Methods and Tools
for Enhancing the Human Role in
Healthcare HMI. Appl. Sci. 2022, 12,
4295. https://doi.org/10.3390/
app12094295
Academic Editor: Junfeng Wang
Received: 25 March 2022
Accepted: 22 April 2022
Published: 24 April 2022
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Review
Augmented Reality: Mapping Methods and Tools for
Enhancing the Human Role in Healthcare HMI
Chiara Innocente , Luca Ulrich , Sandro Moos and Enrico Vezzetti *
Department of Management, Production and Design, Politecnico di Torino, C.so Duca degli Abruzzi, 24,
10129 Torino, Italy
; chiara.innocente@plm.polito.it (C.I.); luca.ulrich@polito.it (L.U.); sandro.moos@polito.it (S.M.)
* Correspondence: enrico.vezzetti@polito.it
Abstract:
Background: Augmented Reality (AR) represents an innovative technology to improve
data visualization and strengthen the human perception. Among Human–Machine Interaction (HMI),
medicine can benefit most from the adoption of these digital technologies. In this perspective, the
literature on orthopedic surgery techniques based on AR was evaluated, focusing on identifying
the limitations and challenges of AR-based healthcare applications, to support the research and
the development of further studies. Methods: Studies published from January 2018 to December
2021 were analyzed after a comprehensive search on PubMed, Google Scholar, Scopus, IEEE Xplore,
Science Direct, and Wiley Online Library databases. In order to improve the review reporting, the
Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were used.
Results: Authors selected sixty-two articles meeting the inclusion criteria, which were categorized
according to the purpose of the study (intraoperative, training, rehabilitation) and according to
the surgical procedure used. Conclusions: AR has the potential to improve orthopedic training
and practice by providing an increasingly human-centered clinical approach. Further research can
be addressed by this review to cover problems related to hardware limitations, lack of accurate
registration and tracking systems, and absence of security protocols.
Keywords:
augmented reality; mixed reality; digital health; medical training; rehabilitation; intraop-
erative; HoloLens; Human–Machine Interaction (HMI); Human–Computer Interaction (HCI)
1. Introduction
The human ability in controlling machines through intuitive and natural behaviors has
been fostered by even more user-friendly interfaces, including gesture-based systems [
1
].
Innovative solutions such as Augmented Reality (AR) and Virtual Reality (VR) play a key
role in this respect, adapting interfaces to individual users/scenarios through the design
of virtual environments powered by biofeedback such as human posture, motion [
1
], and
emotion [2,3].
AR was defined as “the concept of digitally superimposing virtual objects on physical
objects in real space so that individuals can interact with both at the same time” [
4
]. As
perceived by humans, AR is an innovative reality in which the perception of the real
world is enriched and enhanced by new virtual sensory impressions, in a way that they
coexist with the real world [
5
]. This augmented information is provided by sensory stimuli,
either visual or auditory, entirely generated by a computer and then transmitted to the
user through specific tools. One of the most used is Head-Mounted Displays (HMDs),
which are helmets equipped with a monitor capable of displaying holograms of a real-time
video stream in the user’s field of view, such as smart glasses, or showing a completely
artificial 3D-generated world, such as VR headsets [
6
]. In this perspective, registration and
tracking are essential operations to integrate virtual and real information. Registration is
the possibility of overlapping the 3D model on the real surface of the acquired object, for
instance, considering the medical field, a surgical tool, or even an anatomical structure;
Appl. Sci. 2022, 12, 4295. https://doi.org/10.3390/app12094295 https://www.mdpi.com/journal/applsci
