The Role of Virtual Reality Simulation in Acquiring Basic Surgical Skills in Total Hip Arthroplasty by Medical Students- a Prospective Randomized Clinical Trial
Phase: NA
Conditions: Educational Problems, Hip Arthroplasty, Osteoarthritis, Hip, Medical Students
Sponsor: Aristotle University Of Thessaloniki

STUDY PROTOCOL
Title: VR Simulation and Basic Skills in THA
Identifiers: NCT05807828
Document Date: 30/07/2023
Version: Draft 1.0
Principal Investigator: Eustathios Kenanidis, Assistant Professor of Orthopaedic Surgery &
Traumatology
Organisation: 1. Academic Orthopaedic Department, Aristotle University Medical School, General
Hospital Papageorgiou, Ring Road Efkarpia, Thessaloniki, 56403, Greece
2. Centre of Orthopaedic and Regenerative Medicine (CORE), Center for Interdisciplinary
Research and Innovation (CIRI)-Aristotle University of Thessaloniki (AUTH), Balkan Center,
Buildings A & B, Thessaloniki, 10th km Thessaloniki-Thermi Rd, P.O. Box 8318, GR 57001, Greece

Objectives
This prospective randomised trial aims to test if Virtual Reality (VR) simulation helps medical
students who have no surgical experience acquire basic surgical skills in total hip arthroplasty
(THA) by performing two dificult THA steps: the acetabular cup and femoral stem implantation in
a specific position. This study hypothesised that VR training could help young doctors orient
themselves in space and perform more accurate cup implantation in 60° inclination and femoral
stem in 20° anteversion than a control group that had only video teaching from an expert. The
primary outcome will be the a. the difference in the mean implanted cup inclination and femoral
stem anteversion between the VR and control group b. the mean difference between the asked
predefined and the actual implanted cup inclination or cup version between the VR and control
groups. Secondary outcomes will be other differences in completing the task between groups a.
the time needed to complete the task and b. the times asking for assistance c. the number of
mistakes.
Background
All residents traditionally acquire new surgical skills by carefully studying technique guides,
diligently watching procedure videos and working closely with a mentor1,2. However, according
to a study, 96% of residents independently learned how to prepare for surgical procedures3. A
recent study revealed that less than 80% of general surgery residents who have completed their
training were competent in performing complex yet standard medical procedures on patients4.
This emphasizes the importance of looking into additional training methods to fill the gap in
surgical education4.
There are currently a few surgical training methods, including reading surgical technique guides,
using sawbones simulations, and performing cadaveric dissection5-6. However, each of these
methods has its limitations7-9. Sawbones simulation is limited and not reusable, while cadaveric
dissections are expensive, time-consuming and only provide little practice. Basic equipment
knowledge is necessary to use technique guides, but practical exercises may not be possible.
Hence, it's crucial to integrate simulation into medicine, specifically in orthopaedics. VR
technology has been evaluated as a training method for medical doctors or junior surgeons with
promising results in their respective fields of expertise6,10. Although VR technology is advancing
rapidly, there is still a limited number of high-level studies on how it can be used to train
surgeons6,10-12. It is still being determined whether surgeons using VR gain advantages in
identifying anatomical structures, understanding the steps involved in a procedure, improving
their skills during dificult stages of a task, or more eficiently navigating themselves during
surgery.
Methods

This study is a prospective randomised controlled trial with a specific design (figure 1) which is
detailed below.
Recruitment
This prospective randomised trial was approved by our Institutional Review Board (70/2023-
15/02/2023). Eligible study participants included undergraduate medical students at our
university with no previous surgical experience willing to participate. Exclusion criteria included
a. postgraduate medical students b. prior experience in THA or general surgery, c. undergraduate
students unwilling to participate.
One month before the planned VR-THA surgery session, all eligible medical students were invited
to an information session regarding the study through the university's social media. The 101
medical students who fulfilled the inclusion criteria were voluntarily enrolled, providing informed
consent.
Pretest
Immediately after enrollment, medical students were asked to complete a multiple-choice pretest
to quantify their baseline medical and procedural knowledge of hip arthritis and THA. All
participants were unaware and unable to prepare for the pretest assessment, which allows the
test scores to be considered an accurate measure of baseline knowledge.
Video teaching
All medical students were then asked to watch a detailed video explaining the basic anatomy of
the hip joint, the fundamental pathophysiology of hip arthritis, and the THA steps. The video
explained in detail the necessary steps and basic rules that the surgeon must understand to
implant the acetabular cup and femoral stem in a proper position. The video was focused on
practices and methods to understand the intraoperative landmarks to achieve a cup inclination
of 30-60° and stem anteversion of 20° during implantation. All participants were free to watch
the video two to three times to thoroughly understand the principles of the cup and femoral stem
implantation.
Randomisation
All participants were then randomised in the VR or control group for cup and stem training and
implantation by a computerised random number generator. In detail, each participant was
randomised in the VR group for the cup or the stem implantation but in the control group for the
other part of the THA. So, participants enrolled on the VR group for cup training were the control
group for the femoral stem training and vice versa. In this way, each participant was asked to do
one implantation following VR training and the other without VR training. Participants were
privately notified of their randomisation assignment and asked not to disclose their designated
cohort with any other study participant or research personnel. Only a research team member

knew of the cohort assignments during this study. This study personnel did not participate in the
evaluation and analysis of data.
VR training
As mentioned, each participant was randomised and did one implantation, either the acetabular
cup or the femoral stem, following VR training and the other (stem or cup) without VR training,
respectively. This method allowed us to evaluate and compare the performance of participants
who received VR training versus those who did not within the same implantation. It also enables
us to assess individual participants' performance in both scenarios (stem or cup), with and
without VR training.
Before the VR-THA training, participants were asked to complete a survey evaluating their
previous VR technology experience. All VR group participants were then asked to complete three
consecutive VR sessions using the VR system (ORama VR, Geneva, Switzerland), performing cup
or stem implantation based on their group.
Saw bone simulation
After completing VR training, all participants were asked to implant the cup at a 60° inclination in
sawbones and the femoral stem at 20° of anteversion. As mentioned, they performed one
implantation following VR training and the other without VR training.
The sawbones had been reamed and prepared appropriately to accommodate the metal
prostheses from the students steadily. The students did not perform any reaming to the
sawbones. The same saw bone was used for several implantations but was replaced with a new
one when it could no longer handle the implant properly. The cup inclination and stem version
were evaluated using specific goniometers and assessment of photographs taken during
implantation. During implantation in sawbones, a study assistant was present and was instructed
to intervene only if the study participants requested assistance or could not progress through the
task.
Upon completion of the VR-THAs, participants completed a survey focused on their interest in
using VR simulations for surgical skills training and assessing potential negative consequences.
Power Analysis
After reviewing eight recent RCT studies on virtual reality simulation training, it was found that
each study had an average of 14 to 28 participants and an effect size of 0.80 to 0.90. Previous
studies have utilised specific scores to evaluate the impact of trauma or arthroplasty simulator
training on actual performance in real-world scenarios. These evaluations were different from our
measurements. To assess the necessary sample size for our study, we based on the first ten
measurements of cup angle implantation from our medical students; the mean cup angle was
50.40 with a standard deviation of 180. To detect a difference of 20 degrees of implantation

between two groups with a standard deviation of 18 degrees and with a two-sided alpha of 0.05
and power of 80%, at least 26 students were required in its group.
Design of study and sample selection
101 eligible study participants
Video teaching session
Computer randomisation
47 students randomized to VR for cup implantation
(VR Cup) at 60° of inclination (control stem)
3 VR sessions
54 randomized to VR group for the femoral stem
implantation (VR Stem) at 20° of anteversion (control cup)
3 VR sessions
Both groups undertake the cup and stem implantation in the
sawbone models
Analysis of data and conclusion
Figure 1, Study Design
Statistical Analysis Plan (SAP)
The primary outcome was the mean implanted cup inclination and femoral stem anteversion
difference between the VR and control groups. Other outcomes considered between groups
included: a) the duration required to complete the task, b) the frequency of requesting assistance,
and c) the number of errors made.
We used standard statistical methods to gather descriptive statistics. We conducted the
Kolmogorov-Smirnov and Shapiro-Wilk tests to check whether the data followed a normal
distribution. Our statistical tests were two-tailed, and we set the alpha level at 0.05. For
continuous variables that were normally distributed, we used the two-sided independent sample
t-test, while for those that weren't normally distributed, we used the Mann-Whitney U-test. We
compared categorical data using the chi-square test. To determine if using VR had an impact on a
student's task performance, a paired t-test was conducted to compare their outcomes with and
without VR. We performed all statistical analyses using SPSS software (IBM, version 27.0).

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