Content uploaded by Bruno Alejandro Orsatti Sánchez
Author content
All content in this area was uploaded by Bruno Alejandro Orsatti Sánchez on Mar 10, 2022
Content may be subject to copyright.
Vol. 42 | No. 2 | MAY - AUGUS T 2021 | pp 90-103
REVIEW ARTICLE
ib
E-LOCATION ID: 1141
dx.doi.org/10.17488/RMIB.42.2.8
Ecacy of Virtual Reality in Neurorehabilitation of Spinal Cord Injury
Patients: A Systematic Review
Ecacia de la Realidad Virtual en la Neurorrehabilitación de Pacientes con Lesión de Médula
Espinal: una Revisión Sistemática
B. A. Orsatti-Sánchez1, O. Diaz-Hernandez2
1Universidad Nacional Autónoma de México, División de Ingeniería Mecánica e Industrial
2Universidad Nacional Autónoma de México, ENES Juriquilla
ABSTRACT
This systematic review (SR) analyzed the eectiveness of interventions using virtual reality (VR) technology as a
neurorehabilitation therapy in people with spinal cord injury (SCI). The SR was developed under the guidelines of
the PRISMA statement and the recommendations of the Cochrane Collaboration, along with the PEDro and National
Institute of Health scales to assess the risk of bias and methodological quality. The Cochrane, IEEE, BVS/LILACS,
MEDLINE/PubMed, and Web of Science databases were browsed to identify studies that, between 2010 and 2020,
evaluated the ecacy of these therapies. Out of 353 retrieved studies, 11 were nally selected after the application
of the dened inclusion and exclusion criteria. These articles presented good methodological quality as they were
mostly controlled clinical trials that analyzed mixed therapies with conventional therapies. Interventions based
on non-immersive or immersive VR technology that achieved functional motor, balance, and psycho-emotional
health improvement with positive eects on motivation, self-condence, commitment, and active participation
were identied in a total sample of 155 SCI patients. It was concluded that such VR technology is an eective tool
of neurorehabilitation complementary to conventional therapies, which promotes functional improvement in SCI
patients both in the clinic and at home.
KEYWORDS: Spinal cord injury; virtual reality; neurorehabilitation; systematic review
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021 91
Corresponding author
TO: Bruno Alejandro Orsatti Sánchez
INSTITUTION: Universidad Nacional Autónoma de
México, División de Ingeniería Mecánica e Industrial
ADDRESS: Circuito Exterior S/N, Col. Ciudad
Universitaria, C. P. 04510, Coyoacán, CDMX, México
E-MAIL: orsattisba@gmail.com
Received:
21 December 2020
Accepted:
25 March 2021
RESUMEN
Esta revisión sistemática (RS) analizó la ecacia de las intervenciones que utilizan la tecnología de realidad virtual
(RV) como terapia de neurorrehabilitación en personas con lesión de médula espinal (LME). La RS fue desarrollada
bajo los lineamientos de la declaración PRISMA y las recomendaciones de la Colaboración Cochrane, junto con las
escalas de PEDro y del National Institute of Health para evaluar el riego de sesgo y la calidad metodológica. Se revi-
saron las bases de Cochrane, IEEE, BVS/LILACS, MEDLINE/PubMed y Web of Science para identicar estudios que,
entre 2010 y 2020, evaluaron la ecacia de dichas terapias. De 353 estudios recuperados, 11 fueron nalmente
seleccionados tras la aplicación de los criterios de inclusión y exclusión denidos. Dichos artículos presentaron una
buena calidad metodológica, al ser mayormente ensayos clínicos controlados que analizaron terapias mixtas con
terapias convencionales. Se identicaron intervenciones basadas en tecnología de RV no inmersiva o inmersiva que
lograron una mejora funcional motora, de equilibrio y de salud psico-emocional con efectos positivos de motiva-
ción, seguridad, compromiso y activa participación en una muestra total de 155 pacientes con LME. Se concluyó
que dicha tecnología de RV es una herramienta ecaz de neurorrehabilitación complementaria a las terapias con-
vencionales, al promover una mejora funcional en pacientes con LME tanto en la clínica como en casa.
PALABRAS CLAVE: Lesión de medula espinal; realidad virtual; rehabilitación neurológica; revisión sistemática
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
92
INTRODUCTION
Spinal cord injury SCI is related to damage to the
spinal cord resulting from traumatic external force or
non-traumatic disease or degeneration causes. As the
spinal cord SC is the main information conduit con-
necting the brain to the rest of the body, an SCI can
have signiicant physiological consequences below the
level of injury, ranging from no or mild neurological
deicit to a more serious loss of motor, sensory, and
autonomic functions, or even death, mainly depend-
ing on the number of surviving axons 1 2 3.
The World Health Organization highlights that the
incidence of both traumatic and non-traumatic SCI
ranges from 40 to 80 cases per million inhabitants per
year, with 90% of them caused by trauma 1 . Men in
the 20-29 age group and over 70 are at a higher risk of
suffering an SCI, whereas the risk for women appears
between the ages of 15 and 19 and over 60. The male-
to-female ratio is usually 2:1 1.
The increased life expectancy in high-income coun-
tries accounts for a higher SCI prevalence of around
70% for people with quadriplegia and 88% for people
with complete paraplegia as compared to low- and
middle-income countries 1. By 2020, SCI is expected
to be one leading causes of disability globally 4 .
SCI is often associated with various psychological
and social consequences including low rates of school
enrollment, dificulty with schoolwork, work barriers
as reflected in an overall unemployment rate in excess
of 60%, and the fact that 20% to 30% of these patients
show signs of depression 1.
Injuries may be traumatic in the case of fracture, dis-
location, or compression of one or more vertebrae,
mainly as a result of road accidents, falls, or gunshot
wounds. There are also non-traumatic injuries caused
by arthritis, cancer, inflammation, infections, degen-
erative disc disease, or congenital conditions 1 2 3 4.
The degree of paralysis caused by an SCI depends on
the location of the injury, which will determine
whether it is paraplegia or quadriplegia. The latter is
more serious as it causes a partial or total loss of motor
and/or sensory function in all four extremities, trunk,
and pelvic organs when the injury is located in the
C1-C7 segments. In contrast, there is paraplegia when
the injury is located in the T1-S5 segments, causing
functional disorders in the legs, pelvic organs, and
part of the trunk 1 2 3 4 5 6.
The neurological condition of an SCI patient is deter-
mined by the American Spinal Injury Association
ASIA Impairment Scale, which deines 5 levels of
impairment based on the absence or preservation of
motor and sensory function. In a complete injury
grade A, these functions are not present below the
level of injury up to the S4-S5 sacral segments. In con-
trast, when some signals can still be transmitted
below the level of injury, then the injury is incomplete
grades B, C, and D with some preserved motor and/or
sensory function. Grade E describes normal function
of all segments 3 6 7.
Although, so far, the consequences of an SCI are con-
sidered to be irreversible given the SC’s inability to
regenerate, the development of new surgical proce-
dures and the technological advances in the last few
decades have contributed to the design of new rehabil-
itation programs aimed at improving patients’ progno-
sis and quality of life 1 2 8.
Comprehensive, conventional rehabilitation pro-
grams combine physical therapy with occupational
therapy activities. While the former focuses on main-
taining and strengthening muscle function, improv-
ing balance and coordination in both standing and
seating positions, training gait and weight shifting,
and learning adaptation techniques in order to per-
form daily tasks, the latter aims to recover ine motor
skills in order to achieve greater biopsychosocial well-
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 93
being and independence to perform personal care
activities and adapt the impaired abilities to profes-
sional or academic life 1 2 5.
Against this backdrop, the introduction of virtual
reality VR in rehabilitation therapies after SCI seeks
to contribute to motor and cognitive relearning pro-
cesses by arousing patients’ interest in rehabilitation
programs. This is done through a series of game-
based exercises that also instill higher levels of
self-conidence and self-improvement through the
use of new stimuli to enhance the effectiveness of
patients’ physical and cognitive abilities and func-
tions in controlled virtual environments. These game-
based exercises stimulate the patient to perform a
greater number of repetitions and therefore the inten-
sity of the rehabilitation activities increases, which
stimulates neuroplasticity promoting motor relearn-
ing in SCI patients. Some literature highlights the
importance of using VR as a complement to tradi-
tional rehabilitation programs to improve them, since
these usually involve simple and repetitive move-
ments which causes a feeling of boredom, thus reduc-
ing the motivation of SCI patients. Moreover, the cap-
turing patients’ movements enables therapists to
plan, supervise, and adapt exercises in an individual-
ized manner 1 9 10 .
VR or a virtual environment is an IT-based structure
that creates a simulated or artiicial, three-dimensional
3D environment that mimics the real environment
where a person is located. The application of VR devices
depends on the level of technological advancement,
the level of platform complexity, costs, and the ability
to adapt them to different VR environments 9 10.
VR systems fall into three categories according to the
sense of reality of the created virtual environment: 1
in fully-immersive VR, the user wears a headset or
goggles, earphones, and other special peripherals
gloves, haptic hand controllers, etc.; 2 in semi-im-
mersive VR, the user places himself or herself among
four aligned screens on which the virtual environment
is projected and uses peripherals to interact with the
environment with head movements; 3 in non-immer-
sive VR, the user needs a screen monitor, a keyboard,
a mouse, or other peripherals to place himself or her-
self in the VR environment and interact with it 10 .
There is also the so-called “augmented reality,” which
requires the use of a device that enables users to visu-
alize virtual objects overlaid in the real world; this is
often mixed up with semi-immersive VR.
Since VR technology is an innovative tool that has
been applied in the medical ield of rehabilitation and
should be followed up in terms of its most recent
development over the last few years 1, it is important
to compile, synthesize and analyze the evidence
achieved on the advances, effects and level of accep-
tance of VR in the rehabilitation of motor and cogni-
tive functions after SCI.
The objective was to conduct a systematic review SR
with the aim of analyzing the eficacy of VR technol-
ogy in the neurorehabilitation of SCI patients based on
evidence gathered by the studies included in the
review, with an emphasis on: 1 whether VR was inte-
grated into conventional rehabilitation therapies and
the resulting beneits; 2 whether the results of the use
of VR have been compared with those of conventional
rehabilitation therapies; 3 how VR was applied; 4 the
types of SCI analyzed; 5 patients’ acceptability; 6
main limitations observed; and 7 future work.
MATERIALS AND METHODS
Protocol
This SR was conducted following the 27 guidelines
and the flow diagram structure provided by the
PRISMA statement 11 12 13 as well as the recommenda-
tions of the Cochrane Collaboration to perform an
orderly selection of papers according to the proposed
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
94
protocol 1 4 . All this enhanced the quality and presen-
tation of the analysis and brought transparency to the
paper selection process.
Search strategy
Between 1 May and 19 June 2020, an electronic
search was carried out in the COCHRANE, IEEE, BVS/
LILACS, MEDLINE/PUBMED, and WEB OF SCIENCE
databases in order to ind any papers published in the
January 2010-June 2020 period, when most of the
development and research work around the use of VR
technology applied to motor and cognitive rehabilita-
tion 9 took place. Additionally, the search was per-
formed in English and Spanish, without a geographic
delimitation with the purpose of obtaining a global
overview.
The search terms in Spanish consisted of combina-
tions of keywords found in the Descriptores en
Ciencias de la Salud DeCS thesaurus: lesión de
médula espinal, traumatismo de médula espinal, tet-
raplejia, cuadriplejia, paraplejia, realidad virtual, real-
idad aumentada, terapia de exposición mediante real-
idad virtual, juego de video, rehabilitación, and reha-
bilitación neurológica. The search terms in English
included terms found in the Medical Subject Headings
MeSH thesaurus: spinal cord injury, spinal cord
trauma, tetraplegia, quadriplegia, paraplegia, virtual
reality, augmented reality, virtual reality immersion
therapy, virtual reality exposure therapy, video game,
rehabilitation, and neurorehabilitation. The inal
structure of each database search strategy was
adjusted based on syntax, logical operators, tags, and
relevant qualiiers 15 16 17 18.
Eligibility criteria
The inclusion criteria were deined based on the
PICOS model Participants, Interventions, Compa-
rators, Outcomes, Study Design 13 . The review took
into account both controlled and randomized con-
trolled clinical trials 14 1 9 conducted on human sub-
jects that provided empirical evidence of the eficacy
of neurorehabilitation of motor and cognitive func-
tions through virtual reality therapies VRT applied
as a complement or not to physical, occupational, or
mixed therapies, and that allowed for a comparison of
an intervention group with a control group. Quasi-
experimental before-and-after studies were also
considered. The patient population included both
male and female subjects with SCI in the 18 to 85 age
range, with traumatic and non-traumatic, complete
and incomplete injuries, regardless of their ASIA
grades or time since injury.
The studies were required to contain this informa-
tion: population sample, assisted limbs and SCI char-
acteristics, objectives, and aspects of the rehabilita-
tion intervention; VR technology type, effects, and
application method; duration, frequency, and accept-
ability; assessment of the effect of the intervention
compared to conventional therapies; validation or
development of VR software or devices; and interven-
tion eficacy indicators.
Any systematic reviews, meta-analyses, lectures,
abstracts, or studies that were duplicated or not
designed to assess the clinical eficacy of motor or cog-
nitive rehabilitation on SCI, that did not focus on VR as
a therapeutic intervention, or that used electrical
stimulation that could have inf luenced its own results
of the technology under study were excluded.
Similarly, studies that did not it the deined study
time period and were not written in English or Spanish
were also excluded.
The selection of potentially relevant studies was per-
formed in three stages. The irst stage focused on
eliminating duplicate records; the second stage cen-
tered on exclusion of papers according to their title
and abstract; inally, the third stage consisted of a full-
text analysis. The last two stages were guided by inclu-
sion and exclusion criteria 14 .
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 95
Data extraction
Two electronic worksheets were created in order to
obtain detailed information from the studies selected
in an organized manner. The irst worksheet con-
tained demographic and clinical information about
the patient population: mean age, sex, cause and level
of SCI, ASIA impairment grade, type of injury, time
since injury, sample distribution across study groups,
and their respective dropout rates. The second work-
sheet summarized the characteristics of the selected
studies: authors’ names, country and year of publica-
tion, study design, and characteristics of the VR tech-
nology used, information on interventions, sessions,
outcome measures, and conclusions.
Risk of bias assessment
The internal validity of the controlled clinical trials
was assessed using the PEDro scale criteria 2 0. For
before-and-after studies without a control group, the
National Institute of Health Quality Assessment Tool
was applied 21 .
Taking the registered level of evidence as a reference,
the internal validity was rated as poor, fair, good, or
excellent for scores in the 0-4, 5-6, 7-8, and 9-10
ranges, respectively, for PEDro. Comparatively, for the
before-and-after studies, it was rated as poor, fair, or
good in the 0-4, 5-6, and 7-10 ranges, respectively.
Studies rated as with good methodological quality and
low risk of bias were identiied with a score higher
than the mean of 5, while those with scores lower than
the mean of 5 were rated as with poor methodological
quality and high risk of bias.
RESULTS AND DISCUSSION
Paper search and selection process
A total of 353 papers were found, 218 of which
remained after eliminating duplicates. Of these, only
207 could be downloaded. During the second stage of
the selection process, 179 papers were ruled out based
on their title and abstract, and only 28 moved forward
to the inal stage for full-text analysis, where another
17 were excluded, resulting in 11 papers inally
selected for the SR. Figure 1 depicts the paper selec-
tion process listing the exclusion criteria in each stage
based on the PRISMA statement 12.
FIGU RE 1. PRISMA flow diagram of the paper search
strategy and selection process.
A larger number of papers were found from India and
Spain, each represented 27.27% of the studies selected,
while Italy, South Korea, Switzerland, Taiwan, and
Australia each represented only 9.09% of these. Over
the entire search time period, no papers were found
for the years 2013 and 2019. English was the main lan-
guage used in 90.91% of the studies selected.
Risk of bias assessment of selected papers
The results of the controlled clinical trials 22 23 24 25
26 27 2 8 2 9 3 0 and the before-and-after studies 31 32
are presented in Tables 1 and 2, respectively. According
to the PEDro scale, the score for the risk of bias of the
controlled clinical trials was 7.22±1.30, and in the case
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
96
TAB LE 1 . Assessment of the risk of bias of controlled clinical trials according to the PEDro scale.
Table 1
STUDY
CRITERION
D’Addio G,
et. al. (2014)
[22]
Dimbwadyo
Terrer I,
et. al. (2016)
[23]
Dimbwadyo
Terrer I,
et. al. (2015)
[24]
Gil Agudo A,
et. al. (2011)
[25]
Khurana M,
et. al. (2017)
[26]
Lakhani A,
et. al. (2020)
[27]
Tak S,
et. al. (2015)
[28]
Prasad S,
et. al. (2018)
[29]
Sengupta M,
et. al. (2019)
[30]
Randomization
"#
"#
"#
"#
"#
"#
"#
"#
✘
Allocation
concealed
✘
"#
✘
✘
"# "# "# "#
✘
Groups were
similar at baseline
"# "# "# "# "# "# "# "# "#
Blinding
of all subjects
✘
"#
✘
✘
✘
✘
✘
✘
"#
Blinding
of all therapists
✘
✘
✘
✘
"#
✘
✘
✘
✘
Blinding
of all assessors
✘
"#
✘
✘
"#
✘
"# "# "#
Key outcomes
in 85% of the
allocated subjects
"# "# "# "# "# "# "# "# "#
Groups received
planned treatment or
“intention to treat”
"# "# "# "# "# ✘ "# "# "#
Statistical
comparisons between
groups
"# "# "# "# "# "# "# "# "#
Point and variability
measures of
treatment effects
"# "# "# "# "# "# "# "# "#
Total
6
9
6
6
9
6
8
8
7
Level of evidence
Fair
Excellent
Fair
Fair
Excellent
Fair
Good
Good
Good
Risk of bias
Low
Low
Low
Low
Low
Low
Low
Low
Low
Note. "#: yes; ✘: no.
of the before-and-after studies, the National Institute
of Health score was 7.5±0.7. This indicates that the
selected papers have a low risk of bias and a high
methodological quality associated with the evidence
they provide.
Ethical statement
All studies reported that, before the start of the inter-
vention, patients were asked to sign an informed con-
sent letter after they were informed, in writing and
verbally, of the experimental procedures in the study
protocol. The interventions were authorized by the
ethics committees of the participating hospitals 23 24
25 , universities 2 7 28 , sites 26 27 2930 31 or state
agency 32 , with the exception of one 22, which did not
report anything in this regard. Only 3 studies 23 2 5 32
adapted their protocols to the Helsinki Declaration of
the World Medical Association.
Design of selected studies
Of the 11 selected papers, 9 were controlled clinical
trials 8 randomized 22 23 24 25 26 27 28 29 and 1 non-ran-
domized 30 , and 2 were before-and-after studies 31 32.
Controlled clinical trials were those in which the sub-
jects had been allocated to a control group CG or an
intervention group IG and which conducted a pro-
spective analysis. If such allocation had been made
through randomization, then the trial was considered
a randomized, controlled clinical trial. Additionally,
the design of before-and-after studies included sub-
jects that received the same treatment without a con-
trol group 1 4 .
Out of the 9 controlled clinical trials, 8 worked with
parallel groups, and only 1 27 worked with crossover
groups. Only 5 of the 8 randomized controlled clinical
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 97
TAB LE 2 . Assessment of the risk of bias
of before-and-after studies according
to the National Institute of Health.
Tabla 2
STUDY
CRITERION
Sung W, et. al.
(2012) [31]
Villiger M, et. al.
(2017) [32]
Stated study
question or objective "# "#
Eligibility
criteria (subjects) "# "#
Representative
participants "# "#
Enrollment of all
eligible participants "# NR
Sample size
sufficiently large
✘
✘
Intervention
clearly described
and delivered
"# "#
Clearly define
outcome measures
✘
✘
Blinding
of all assessors NR
✘
More than 20% of
participants followed-
up after baseline.
"# "#
Statistical analysis (p)
"#
"#
Outcome measures
taken multiple times "# "#
Group level
statistical analysis
NA NA
Total
8
7
Level of evidence
Good
Good
Risk of bias
Low
Low
Note.
"#
: yes; ✘: no; NR: not reported; NA: not applicable.
trials were blinded and reported the randomization
technique used: opaque envelopes containing sequen-
tial numbers 2 3, computer-generated random num-
bers 26 , the “randbetween” function in Excel 27,
Random Allocation 2.0 software 28 , and an unspeci-
ied ixed randomization method 29. In the case of the
non-randomized study 30, patients were assigned to
the IG and CG based on their demographic characteris-
tics, which is not considered an adequate randomiza-
tion method by PEDro 20 and the Cochrane
Collaboration 14 .
As far as blinding is concerned, 4 controlled clinical
trials and 2 before-and-after studies had no blinding 22
24 25 27 31 32. Moreover, of the 5 controlled clinical tri-
als, 2 were single-blinded to the assessors 28 29 , and 3
were double-blinded to both the subjects and the asses-
sors 23 30 or to the therapists and the assessors 2 6 .
It should be noted that only 3 papers 23 29 32 included
a long-term follow-up on the effects of VRT on subjects
over time.
Population characteristics
All papers reported their inclusion and exclusion cri-
teria for subject eligibility, and only 9 23 25 2 6 27 28 29
30 31 32 indicated their recruitment sources.
The total population sample analyzed was made up of
243 patients with SCI, with 4 studies 22 25 26 28 having
a 1:1 distribution between the IG and the CG. Only 2
randomized controlled trials 27 29, 1 controlled clini-
cal trial 3 0, and 1 before-and-after study 32 reported 1
or 4 dropouts in both groups 27 29 or only in the inter-
vention group 30 32, with a total of 15 patient drop-
outs. The mean age of the total population analyzed
was 40.25 years for both groups, with a majority of
men 78.68% in the reported population n=197 in 9
studies see Table 3.
Traumatic injuries were found in 86% of the popula-
tion analyzed n=150 by 8 studies 23 24 25 2 6 2 7 29 31
32 and only 1 study 30 reported both traumatic and
non-traumatic injuries without providing precise data.
As to the level of injury, all studies n=209 but one 22
observed that 50.72% of injuries were located in the
cervical spine, 44.97% at the thoracic level, and 4.31%
in the lumbar spine. Most studies worked with recently
injured patients < 6 months, and 4 other studies 28 29
31 32 worked with patients who had had their injuries
for more than one year.
Most SCI were incomplete 58.37% in the reported
population n=209, and only 1 study 26 did not report
on this. Regarding the level of impairment of all
patients n=167, according to the ASIA scale, most had
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
98
TAB LE 3 . Demographic characteristics of patients included in the studies.
Table 3
STUDY
SAMPLE/DROPOUT
AGE (YEARS)#
SEX
AUTHORS IG CG IG CG
IG
CG
M
F
M
F
D’Addio G, et. al. [22]
15/0
15/0
43±18.7
✘
Dimbwadyo Terrer I, et. al. [23]
16/0
15/0
34.53±13.71
40.27±13.61
10
6
12
3
Dimbwadyo Terrer I, et. al. [24]
6/0
3/0
54.3±9.86
44.17±22.92
5
1
2
1
Gil Agudo A, et. al. [25]
5/0
5/0
36.20±10.41
49±6.11
1
4
3
2
Khurana M, et. al. [26]
15/0
15/0
29.47±7.48
29.8±7.32
14
1
14
1
Lakhani A, et. al. * [27]
10/4
14/4
56.20±20.74
48±16.21
10
0
6
8
Tak S, et. al. [28]
13/0
13/0
49.54±8.25
43.08±11.23
10
3
10
3
Prasad S, et. al. * [29]
12/1
10/1
23.7±5.2
33.9±7.1
11
1
10
0
Sengupta M, et. al.** [30]
25/4
12/0
28
30.5
17
4
10
2
Sung W, et al.*** [31]
12
NA
28.5
NA
10
2
NA
Villiger M., et. al. */*** [32]
12/1
NA
60±10.2
NA
✘
NA
Note. IG: intervention group; CG: control group; M: male; F: female; ✘: information not provided; NA: not applicable.
*Data before dropout. **Data after dropout. ***No control group. #The values are represented as mean ± standard deviation.
grade A injuries 47.31%, followed by grade B 23.35%,
grade D 15.57%, and grade C 13.77%. Two studies 22
26 reported, with no details, that they had worked
with certain ASIA grades, and one 31 did not address
this issue.
The clinical characteristics of each population group
analyzed are presented in Table 4.
Characteristics of virtual reality
The studies used different types of commercial VR
technologies, including video game consoles, special-
ized VR peripherals and systems designed for rehabil-
itation, as well as devices developed by the research
teams see Table 5.
Only one study used a commercial, fully-immersive
VR system Oculus Go VR headset 27 , while the other
10 studies used non-immersive VR systems 22 23 24 25
26 28 29 30 31 32. Four of them 22 26 28 2 9 were based on
Nintendo and Sony commercial consoles, with their
video games mainly sports and recreational and
compatible peripherals that, in few cases, were
reported to be adapted for use in rehabilitation of cer-
tain impairment grades for instance, only one men-
tioned attaching the Wiimote controller to the hand
with bandages or a glove in cases of weak grip 2 9.
Additionally, Rhetoric system 30 only used Microsoft
Kinect peripheral. Other studies used motion sensing
devices for rehabilitation such as YouKicker with four
wireless accelerometers 32, TOyRA 23 25 based on
ive wireless inertial sensors, and CyberGlove 24
with 22 resistive bend sensing technology and vibrot-
actile stimulators. One study developed a driving
simulator 31 using an adapted real car mounted on a
one-axle tiltable platform to virtually control accelera-
tion and braking.
Regarding those studies where their VRT used com-
mercial consoles along with their video games, only
one 26 explicitly mentioned the adaptation of their
virtual environments for rehabilitation purposes with-
out providing further details. On the other hand, those
studies where commercial video games were not used
as virtual environment, two of them were developed
by the research teams 24 32 and only one speciied the
use of Unity 3D 3 2 as graphic engine for its develop-
ment. In the case of the Rhetoric 30 and TOyRA 23 25
systems, their games were designed for neurorehabili-
tation purposes by specialized teams of Rehametrics
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 99
TAB LE 4 . Clinical characteristics of patients included in the studies.
Table 4
STUDY CAUSE OF SCI LEVEL OF SCI ASIA IMPAIRMENT SCALE TYPE OF INJURY
TIME
AFTER
INJURY
(MONTHS)
Δ
AUTHORS
IG
CG
IG
CG
IG
CG
IG
CG
IG CG
T
NT
T
NT
Cx
Tx
L
Cx
Tx
L
A
B
C
D
A
B
C
D
Co
In
Co
In
D’Addio G,
et. al. [22]
✘
✘
0 0 NR 0 0 N R 0 15 0 15
✘
Dimbwadyo
Terrer I,
et. al. [23]
15 1 14 1 16 0 0 15 0 0 11 5 0 0 10 5 0 0 11 5 10 5 4.31
±2.06
5.6
±2.5
Dimbwadyo
Terrer I,
et. al. [24]
4 2 2 1 1 5 0 0 3 0 5 0 0 1 3 0 0 0 5 1 3 0 5.83
±2.99 5±1
Gil Agudo A,
et. al. [25]
4 1 2 3 5 0 0 5 0 0 3 2 0 0 2 3 0 0 3 2 2 3
4.2
±0.98
5.8
±1.17
Khurana M,
et. al. [26]
15 0 15 0 0 15 0 0 15 0 NR 0 0 NR 0 0 NR
3
±0.66
2.67
±0.72
Lakhani A, et.
al.
*
[27]
9 1 8 6 7 2 1 6 3 5 7 1 2 0 3 0 7 4 7 3 3 11
4.5
±2.12
4.2
±2.65
Tak S,
et. al. [28]
✘
4 9 0 5 8 0 10 3 0 0 10 3 0 0 10 3 10 3
21.69
±8.66
22.38
±9.36
Prasad S,
et. al.
*
[29]
12 0 10 0 12 0 0 10 0 0 1 6 2 3 4 3 2 1 1 11 4 6
15.2
±11.2
10.2
±5.7
Sengupta M,
et. al.** [30] NR 7 14 0 4 8 0 6 5 5 5 4 3 3 2 6 15 4 8 < 6
Sung W,
et. al.
***
[31]
11 1 NA 3 7 2 NA
✘
NA 8 4 NA 23.2 NA
Villiger M, et.
al.
*/***
[32]
8 4 NA 6 5 1 NA 0 0 2 10 NA 0 12 NA 96 NA
Note. IG: intervention group; CG: control group; T: traumatic; NT: no traumatic; Cx: cervical; Tx: thoracic; L: lumbar;
Co: complete; In: incomplete; ✘: information not provided; NR: not reported but was mentioned; NA: not applicable.
*Data before dropout. **Data after dropout. ***No control group. ΔThe values are represented as mean ± standard deviation.
and INDRA systems companies, respectively. It should
be noted that the design of the environments for
TOyRA was developed on the basis of therapeutic
guidelines for SCI rehabilitation, while for another
study 32 it was mentioned that the therapists partici-
pated in the design of the clinically virtual exercises.
In addition, the fully-immersive VR system 2 7 relied
mainly on the use of pre-recorded videos from National
Geographic which were not properly virtual environ-
ments and without any possibility of patient interac-
tion. Details on the orientation of the different virtual
environments in rehabilitation of balance control, ADL
autonomy, motor function, psycho-emotional health
and driving skills are included in Table 5.
The VRT was administered using avatars in virtual
environments 2 2 26 2 8 29 , mirroring of movements
made through an avatar 23 25 30, limb control in a
irst-person virtual environment 24 3 2, activities of
daily living ADL in virtual everyday spaces 23 24 25
26 , projection of pre-recorded 360º real-life natural
environments 27 and driving skills training 31. It
should be noted that in the TOyRA system, the avatar
could be personalized based on the patient’s anthro-
pomorphic traits which increases the patient’s sense
of presence in the virtual environment.
Intervention characteristics
All studies 22 23 24 25 26 27 28 29 30 31 32 provided
information on the baseline assessment carried out
prior to the start of VRT. In controlled clinical trials,
the IG was treated with a mixed therapy including VRT
22 23 24 25 26 27 28 29 30 comprising several VR technol-
ogies, along with traditional rehabilitation therapy
TRT 22 or conventional therapy CT 23 24 25 26 28 27
29 30, based on occupational and/or physical therapy
and in certain cases, supported by other treatments
27. Patients assigned to the CG were administered the
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
100
Table 5
STUDY DESIGN VR INTERVENTIONS
FREQUENCY
DURATION FOLLOW-
UP
OUTCOME
MEASURES MAIN FINDINGS
D’Addio G,
et. al. (2014)
Italy [22]
Randomized
controlled
clinical trial,
nonblinded.
Nintendo Wii Fit +
Balance board + Games
(“Table Tilt”, “Balance
Bubble” and “Deep
Breathing”).
IG(n:15): VRT
(multidirectional balance
and static postural control
training) + TRT.
CG(n:15): TRT (balance
training with
active/passive UL and LL
stretching and exercises to
increase strength and
improve posture).
Total period = 12 weeks.
IG: 3 VRT sessions +
TRT for 60 [min] per
week.
CG: 3 TRT sessions of
60[min] per week.
BBS (Berg Balance Scale),
SCIM (Spinal Cord
Independence Measure),
COP EO and EC
(Posturographic Index:
Center of Pressure) and
Romberg Index.
An improvement in
balance control was
observed in both IG and
CG. However, the
improvement was grater in
the IG, particularly in
balance and self-
confidence to perform
tasks without external
support. The Wii Fit
system was potentially
acceptable as an adjunct to
TRT. Given its low cost
and intuitive use, it could
be used as a rehabilitation
tool at home under
supervision.
Dimbwadyo
Terrer I,
et. al. (2016)
Spain [23]
Pilot
randomized
controlled
clinical trial,
double-
blinded.
TOyRA wireless system
(LCD monitor + inertial
sensors Xsens + Virtual
environment with 3D
interactive objects and
personalized avatar.
IG(n:16): VRT (ADL
training with dominant
UL) + CT.
CG(n:15): CT (OT: ADL
training + PT:
strengthening exercise and
active/passive
mobilizations of UL).
Total period = 5 weeks.
IG: 3 VRT sessions of 30
[min] + 5 CT sessions of
90 [min] per week.
CG: 5 CT sessions of 90
[min] per week.
Follow-up (n=22: 11 per
group): Only CT 3
months after treatment for
both groups.
SCIM III (self-care
subscore), MI (Motricity
Index), BI (Barthel Index),
MB (Muscle Balance),
FIM (Functional
Independence Measure),
QUEST 2.0 (Quebec User
Evaluation of Satisfaction
with Assistive
Technology) and
Satisfaction Survey (Likert
scale).
The effects of an intensive
and repetitive VRT + CT
compared to those of CT
alone produced similar
functional changes in the
IG and CG in UL
performance in patients
with complete tetraplegia.
A high level of patient
satisfaction was observed
as a result of the gaming
aspects. The TOyRA
system as a complement to
CT can be useful to
increase duration of
therapy, as well as
engagement and
motivation during the
rehabilitation process.
There were no reports of
vertigo, motion sickness or
muscle pain.
Dimbwadyo
Terrer I,
et. al. (2015)
Spain [24]
Pilot
randomized
controlled
clinical trial,
nonblinded.
CyberGlove (resistive
bend-sensors and vibro-
tactile feedback) + LCD
Philips monitor
(autostereoscopic 3D) +
First-person virtual
environment with 3D
objects
IG(n:6): VRT (reach and
release movements with
UL in ADL and trunk
balance control) + CT.
CG(n:3): CT (OT: ADL
training and UL Functional
exercises + PT:
assisted/active
mobilizations of UL and
trunk balance exercises).
Total period = 2 weeks.
IG: 2 VRT sessions of 30
[min] + 2 CT sessions of
30 [min] per week.
CG: 2 CT sessions of 30
[min] per week.
MB, BI, SCIM (self-care
subscore), NHPT (Nine
Hole Peg Test) with JHFT
(Jebsen Taylor Hand
Function Test) + two
implemented parameters:
“Repeatability” and
“Normalized Trajectory
Length”.
The results between the
groups were similar,
although the IG improved
in dexterity, coordination
and fine finger movement
during reaching
movements. The results
showed the usefulness of
VRT in ADLs
rehabilitation as a
complement to CT. VRT
(CyberGlove) based on
functional parameters,
such as normalized
trajectory length and
repeatability, adapted the
level of difficulty of the
tasks to patients’
individual abilities.
Prolonged repetitive
movements led to
functional improvement.
There were no reports of
vertigo, motion sickness or
muscle pain.
TAB LE 5 . Characteristics of included studies.
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 101
Gil Agudo A,
et. al. (2011)
Spain [25]
Randomized
controlled
clinical trial,
nonblinded.
TOyRA system.
IG(n:5): VRT (ADL
training with UL) + CT.
CG(n:5): CT (OT: ADL
training + PT: active-
assisted-resistive
mobilizations of UL
joints).
Total period = 5 weeks.
IG: 15 VRT sessions of 30
[min] on alternated days +
7 OT sessions of 30[min]
and 30[min] of PT per
week.
CG: 7 OT sessions of
30[min] and 30[min] of PT
per week.
ROM (Range of Motion),
BI, FIM, SCIM II, NHPT,
JTHFT and MI.
The use of VRT + CT
produced similar results in
both groups with
tetraplegic patients,
although an improvement
in UL function was
observed in the IG vis-à-
vis CT alone, with
improved dexterity, pincer
grasp, and coordination as
well as a slight improved
ROM for shoulder flexion-
extension and forearm
pronation. The TOyRA
system can be used as a
complementary therapeutic
tool with CT.
Khurana M,
et. al. (2017)
India [26]
Randomized
controlled
clinical trial,
double-
blinded.
Sony PlayStation 2 + Eye
Toy + 3 adapted games
(“Birds and balls”,
“Soccer” and
“Snowboard”).
IG(n:15): VRT (sitting
balance in ADL with UL
and trunk) + CT.
CG(n:15): CT (OT:
balance in ADL moving
upper body over/outside
support base + PT:
stretching of LL, mat and
range of motion exercises).
Total period = 4 weeks.
IG: 5 VRT sessions of 25
[min] + 5 PT sessions of
20 [min] per week.
CG: 5 OT sessions of 25
[min] + 5 PT sessions of
20 [min] per week.
mFRT (modified
Functional Reach Test), t-
shirt test and SCIM III
(self-care subscore).
Game-based (PlayStation
2) VRT + CT improved
sitting balance and
functional performance in
patients with low
paraplegia in the IG vis-à-
vis CT alone. Increasing
the level of difficulty of
the activities and making
them more intense
contributed to motor
function recovery by
promoting neuroplasticity.
Patients’ motivation was
not measured, but
participants showed
interest and enthusiasm for
VRT.
Lakhani A,
et. al. (2020)
Australia [27]
Randomized
controlled
clinical trial,
nonblinded.
Oculus Go headset + 9 real
natural landscapes 360 [º]
videos (London's Natural
History Museum and
National Geographic).
IG(n:10): VRT (videos for
psycho-emotional health)
+ CT
CG(n:14): CT (OT + PT
based on each participant’s
goals and level of injury +
psychological leisure
therapy) + VRT.
Total period = 2 weeks.
IG: Week 1: 3 VRT
sessions of 20 [min]. Week
2: 7 OT sessions + 20
[min] of PT.
CG: Same as IG but in
reversed per week.
PHQ-8 (Patient Health
Questionnaire 8) and
Feeling Intensity
Evaluation (adapted
Depression Intensity Scale
Circles).
VRT (real landscape
projection) + CT promoted
inpatients’ short-term
psycho-emotional health as
reflected in high levels of
happiness, relaxation and
feeling good, even when
performed at the hospital.
This had a positive impact
on patients’ engagement
with rehabilitation. VRT
can have a favorable
impact as a complement to
CT. Signs of depression
were observed in the IG
after VRT, possibly given
that they were the first
ones to experience it
during the first week and
not during the second one.
Tak S, et. al.
(2015) South
Korea [28]
Randomized
controlled
clinical trial,
single-blinded.
Nintendo Wii + Wiimote +
Wii Sports and Wii Sports
Resort games with avatar
(tennis, ping pong, box,
golf, bowling, frisbee,
canoeing and swordplay).
IG(n:13): VRT (static and
dynamic sitting balance
training with UL and
trunk) + CT.
CG(n:13): CT (OT: sitting
balance training, transfer
to toilet and positioning +
PT: stretching and
strengthening).
Total period = 6 weeks.
IG: 3 VRT sessions of 30
[min] + 5 CT sessions of
90 [min] per week.
CG: 5 CT sessions of 90
[min] per week.
mFRT, t-shirt test and the
use of a forceplate for
static balance ability,
postural sway distance and
velocity.
Game-based VRT
(Nintendo Wii) + CT
improved static and
dynamic sitting balance for
IG. It helped with raising
the arms out to the sides
and the head, improved
balance in SCI, and had a
positive effect on sitting
postural balance. VRT can
be used as a complement
to CT both in hospital or
home-based programs as it
is an accessible system that
can arouse patients’
motivation and interest.
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
102
Prasad S,
et. al. (2018)
India [29]
Pilot
randomized
controlled
clinical trial,
single-blinded.
Nintendo Wii + Wiimote +
Wii Sports Resort games
(ping pong, bowling,
cycling and swordplay
speed slice).
IG(n:12): VRT (dominant
hand movements
depending on the game) +
CT.
CG(n:10): CT (OT:
functional tasks for
handling objects + PT:
strength training with
active or active-assisted
movements of the target
UL).
Total period = 4 weeks.
IG: 3 VRT sessions of 30
[min] + 3 CT sessions of
30 [min] per week.
CG: 3 CT sessions of 30
[min] per week. Follow-
up (IG=11, CG=9): 6
weeks after treatment.
Follow-up (IG=11,
CG=9): 6 weeks after
treatment.
CUE (Capabilities of
Upper Extremity
questionnaire), BBT (Box
and Block Test), SCIM-
SR (selft-report),
WHOWOL-BREF (World
Health Organization
Quality of Life-BREF) and
Satisfaction Evaluation
based on VAS (Visual
Analog Scale).
An intensive and repetitive
VRT + CT improved UL
motor function, similar as
did CT alone. However,
the IG had higher scores.
A high level of satisfaction
and adherence to treatment
was reported, along with a
drive for finding new self-
improvement strategies
based on game scoring and
level of difficulty. VRT
(Nintendo Wii) was
considered as an adjunct to
CT that could be used to
develop home-based
therapies and increase
therapy duration. The
improvements achieved
were maintained during
the follow-up period. No
adverse effects were
reported.
Sengupta M,
et. al. (2020)
India [30]
Controlled
clinical trial,
nonrandomized,
double-blinded.
Rhetoric system
(Microsoft Kinect +
Rehametrics’ neurological
rehabilitation games +
monitor).
IG(n:25): VRT (static and
dynamic balance control
training with UL and
trunk, and static gait with
LL) + CT.
CG(n:12): CT (based on
patient needs and goals).
Total period = 3 weeks.
IG: 5 VRT sessions of 30
[min] with 5 [min] of
warm-up per week. CT
time was not reported.
CG: Not reported.
BBS, POMA-B
(Performance-Oriented
Mobility Assessment-
Balance) and FRS
(Functional Reach Score).
The improvements
produced were similar in
both groups, although the
IG achieved a significant
improvement in all
outcome measures. The
completeness of motor
injury did not influence
the effects of intervention
on balance VR training.
VRT is an enjoyable
adjunct to CT that can be
used for rehabilitation of
balance control in SCI
patients. Virtual objectives
promoted full-body reach
movements of the joints
similar to those of ADLs.
Neck and back pain were
reported during the initial
training sessions.
Sung W,
et. al. (2012)
Taiwan [31]
Before-and-
after study,
noncontrolled,
nonrandomized,
nonblinded.
Driving simulator (5
virtual driving routes and a
single-axis tilting
platform) developed by the
authors.
IG(n:12): VRT (recovery
and enhancement of
driving skills with UL and
LL).
Total period = 6 weeks.
IG: 2 VRT sessions of
30[min] or a bit more per
week.
Total driving time,
average speed, center-line
violation, stop-line
violation, collisions, and
steering or breaking
stability
After five VRT sessions,
improvements were
observed in driving skills.
The VR driving simulator
had a positive effect on
SCI driver training
rehabilitation programs as
a result of the challenges
posed by the simulator’s
tilt effect in sitting posture
and balance.
Villiger M,
et. al. (2017)
Switzerland
[32]
Before-and-
after study,
noncontrolled,
nonrandomized,
nonblinded.
YouKicker
(accelerometers) + 5
virtual environments
created with Unity 3D
(“Footbag”, “Hamster
Splash”, “Get to the
Game”, “Star Kick” and
“Planet Drive”) +
computer monitor.
IG(n:12): VRT (balance
training and
sitting/standing LL
mobility with ADL: ankle
dorsal flexion, knee
extension and leg ad-
/abduction).
Total period = 4 weeks.
IG: 16-20 VRT sessions
of 30-45 [min] per week.
(VRT with supervision by
a physical therapist in the
first session).
Follow-up (IG=11):
1-2 months after
treatment.
LEMS (Lower Extremity
Motor Score), BBS, TUG
(Timed Up and Go),
WISCI II (Walking Index
for Spinal Cord Injury),
SCIM III, 10m and 6min
Walking Test, Motivation
Evaluation scored by 11-
point NRS (Numeric
Rating Scale) and the
Patients’ Global
Impression of Change
(PGIC).
Unsupervised home-based
VRT improved muscle
strength, balance and LL
functional mobility
promoted by structural
brain plasticity due to
intensive and repetitive
movements. In addition,
high levels of motivation
were reported for all
participants. It was noted
that having trained with
specific isolated
movements, there was an
overall motor functional
improvement. The system
is a useful tool for
neurorehabilitation follow-
up during or after
supervised therapy in
home-based training
programs reducing cost
and time of transportation.
The presence of a therapist
during VRT may help with
motivation. There were no
reports of pain or
spasticity.
Note. IG: intervention group; CG: control group; VRT: Virtual Reality Therapy; TRT: Traditional Rehabilitation Therapy; OT:
Occupational Therapy; PT: Physiotherapy; CT: Conventional Therapy (OT + PT); n: number of patients; ADL: Activities of Daily
Living; UL: Upper Limb; LL: Lower Limb; EO: Eyes open; EC: Eyes closed; SCI: Spinal Cord Injury.
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 103
same treatment as those in the IG but without the VR
component. The before-and-after study protocols only
had one group of subjects on which they experimented
with VRT independently 31 32.
Most VRT, TRT, or CT activities focused on balance
control 22 24 26 28 30 32, ADL autonomy 23 24 2 5, other
functional limb movements 29 32, psycho-emotional
health 27 , and driving skills 31. Only 2 studies based
their CT on each subject’s goals or needs 27 30.
It should be highlighted that in 5 studies, VRT aimed
at improving upper limb UL function 23 24 25 2 8 29 ;
in 1 study, VRT aimed at improving lower limb LL 32
function, and in 4 studies, VRT aimed at improving
both UL and LL 22 26 30 31 function. Some therapies
also included trunk movements 22 24 26 28 30.
In most cases, VRT was supervised by an occupa-
tional therapist 23 30, a physical therapist 22 28 30 31,
or several therapists 26 32.
The number of VRT sessions varied from 3 to 80, with
a frequency between 2 and 20 times per week over a
total VRT period of 2 to 12 weeks, mostly with 30-min-
ute sessions. Most of the studies were conducted at
specialized centers or hospital departments 23 2 4 25 27
28, or rehabilitation centers 22 26 29 30 31, while only 1
study 32 reported that VRT was administered at the
patient’s home and set up by a therapist.
It should be pointed out that in 7 studies 23 2 4 25 26 29
30 32, the level of dificulty of the virtual games or
activities was adjusted increasing/reducing speed or
number of repetitions, changing object appearance,
and interaction parameters depending on the level of
progress achieved by patients in the various VRT exer-
cises. It is worth noting that one intervention 31 ,
instead of including gradually increasing levels of difi-
culty according to the patient’s progress, created a
more challenging scenario that brought together all the
isolated activities done in previous scenarios. The
details of the interventions analyzed are included in
Table 5.
Outcome measures
The various scales, indices, or instruments used to
evaluate the effects of interventions on UL and LL
motor function, balance, functional independence in
ADL, and pyscho-emotional health associated with
depression are presented in Table 5 according to the
VRT applied in each study and where at least two or
TAB LE 6 . VRT effects achieved based on rehabilitation goal.
Table 6
STUDY BALANCE CONTROL MOTOR FUNCTION
PSYCHOLOGICAL
ASPECTS
MOTIVATION/
SATISFACTION
D’Addio G, et. al. [22]
"#*
Dimbwadyo Terrer I, et. al. [23]
✘
"#
Dimbwadyo Terrer I, et. al. [24]
"#
"#
Gil Agudo A, et. al. [25]
"#*
Khurana M, et. al. [26]
"#*
"#*
Lakhani A, et. al. [27]
"#*
Tak S, et. al. [28]
"#*
Prasad S, et. al. [29]
"#*
"#
Sengupta M, et. al. [30]
"#
*
Sung W, et. al. [31]
"#*
Villiger M, et. al. [32]
"#*
"#*
"#
Note.
"#
: at least one relevant effect; ✘: no relevant effect achieved. *statistically significant (p< 0.05).
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
104
more combinations were used. Only 3 studies 23 29 32
assessed the level of acceptance and motivation using
patient satisfaction scales after the intervention.
Other studies came up with new outcome measures,
such as the normalized trajectory length to measure
movement trajectory precision improvement, and
repeatability to measure movement precision improve-
ment 2 4. Similarly, kinematic variables 25 or the simu-
lator’s own aspects 3 1 were used to evaluate the
effects of VRT.
Eects of virtual reality therapy
There were 7 controlled clinical trials 23 2 4 25 2 6 27 2 8
30 that did not report signiicant differences between
both intervention groups at baseline, which means
that at the start of the studies, patients were in similar
functional conditions. The effects of VRT are consoli-
dated in Table 6. From then onwards, VRT was under-
stood as being a mixed or as an individual therapy.
Only 9 papers reported a statistically signiicant dif-
ference in VRT p<0.05 in balance control 22 26 28 30
32 , motor function 25 26 29 31 32, and psychological
aspects 27 . Furthermore, 3 studies assessed the effect
size of the interventions, which was found to be
between medium and large, with Cohen’s d values
between 0.41 and 0.84, and an η2 between 0.21 and
0.95 23 26 27. Similarly, the level of satisfaction 23 29
and motivation 32 were assessed, and one study 26
subjectively observed a high level of interest and
enthusiasm in patients during VRT.
Side eects of virtual reality
There were no adverse or side effects reported, such
as motion sickness, vertigo, muscle pain, or spasticity
23 24 29 30 32. Only one study 27 reported signiicant
signs of depression in its IG immediately after VRT.
Another study 29 reported dificulty in holding the
Wii-mote controller due to weak grip in seven patients,
and another one mentioned 30 that during the inter-
vention there were some cases of back pain and ortho-
static hypotension that were controlled and subsided
with medication, allowing the therapy to continue as
they were not deemed serious side effects.
Limitation of the studies
Some of the controlled clinical trials indicated that
their design did not include any type of blinding 2 2 24
25 27 , concealed allocation 22 24 25 30, or even ran-
domization 30. In the before-and-after studies 31 32, it
was clear that there was no blinding as they did not
include a CG in their design, which implied certain
bias in the results.
Regarding subjects and protocols, it was not possible
to generalize results given the limitations observed,
such as small sample size 23 24 25 28 29 30 32, with par-
ticular SCI characteristics 23 26 28 29 32 and very few
variations in demographic data 27, as well as the fact
of having single selection sources 26 .
As far as interventions are concerned, the identiied
limitations included: the short duration of interven-
tion 23 24 2 7 29 3 1; most studies did not follow-up on
the results, except for 3 of them 23 29 32; only 1 study
explicitly recognized having included a small set of
virtual exercises as a limitation 3 0; the weight of any
other health condition that could have influenced the
results was not considered 27; and the diversity of
interventions did not make it possible to set guidelines
on intensity, dosage, and duration of VRT 30 .
As to the limitations derived from the VR technology,
the need to have more sophisticated and modern soft-
ware commercial or especially designed games and
hardware consoles, controllers, headsets, sensors,
graphic cards was identiied for VRT to be more effective
26 30. The Wii Fit system especially stood out, because as
it is a black box system, it was not possible to monitor
several game parameters included in the VRT, thus limit-
ing its contribution to improving balance control 22.
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 105
Three studies pointed out limitations in terms of
interaction with VR devices, which could have affected
the obtained results. Such was the case with the
Nintendo Wii console 28 2 9, where the patient required
some prior training before using it.
Patients with acute SCI could not use it because they
could not maintain balance, hold the controller, or
even generate motion, especially in the case of higher
cervical injuries. The third study identiied predeined
VR scenarios 360º recordings as a limitation since
patients could not interact with them 27 .
Future development
Based on the above-mentioned limitations, the sub-
jects’ proiles, and the intervention protocol, a sugges-
tion was made to use a broader patient sample 23 24 25
26 27 29 30 31 32, with different SCI characteristics
than the ones included in the studies 26 29 31 32,
involving several recruitment sites 30, and including
more VRT sessions 23 2 4 to better identify VRT bene-
its, the system’s critical characteristics, and the vir-
tual exercises that achieved better results 2 4.
The before-and-after studies 31 32 along with one
controlled clinical trial 30 proposed to carry out future
interventions based on a blinded, randomized, con-
trolled clinical trial with long-term follow-up design
30 31 32 to reduce the risk of bias and monitor the
sustainability of the intervention by means of a longi-
tudinal study to validate the level of skill improve-
ment achieved 31.
Regarding types of VR devices, a proposal was made
to conduct studies that combine VRT such as TOyRA
with robotic devices Amadeo for telerehabilitation
based on VR motion capture systems 25 and develop
new VR devices for rehabilitation with a focus on ADL
or relevant exercises/skills designed to simulate more
realistic situations with higher levels of dificulty
according to different SCI levels 31.
For interventions that used mixed VRT 22 24 29 30, a
proposal was raised to conduct new studies to assess
the impact of VRT individually, compare the results of
home-based therapies with those achieved at the
clinic 32, and develop methods to exercise system-
atized balance control with a focus on SCI level and
sitting balance control 28 .
Main ndings, quality of evidence
and potential application
This SR included a total sample of 243 subjects from
the 11 papers analyzed, out of which 155 experi-
mented with VRT 63.78%. There was a similar num-
ber of paraplegic 69 and tetraplegic 67 patients, and
14 patients did not complete the intervention. Patients
treated with VRT mostly had ASIA grade A/B impair-
ment 42.20% and 20.18%, followed by ASIA grades
C/D 16.51% and 21.10%, with an absence of motor
function and little or no sensory perception below the
neurological level of injury, with a major focus on UL.
Three types of studies were taken into consideration:
randomized controlled clinical trials 2 2 23 24 25 2 6 27
28 2 9, one non-randomized controlled clinical trial 30,
and before-and-after studies 31 32. Over half of the
studies 23 26 28 29 30 31 32 had a good or excellent
level of evidence with low risk of bias and achieved
statistically signiicant results 26 28 29 30 31 32 with
regard to VRT.
The controlled clinical trials exhibited an adequate
level of evidence given that they were mostly random-
ized 2 2 23 24 25 2 6 2 7 28 29 , with 6 of them having an
adequate sample size 22 23 26 27 2 8 2 9. Seven 23 24 25
26 27 28 30 did not show any confounding bias upon
observing a similar baseline functional condition
among patients. Regarding blinding, half of them did
not describe any blinding method 22 24 25 27 , while
the remaining half that reported having used a dou-
ble-blind 23 26 or single-blind 2 8 2 9 method reduced
their detection bias upon including blinded assessors.
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
106
Given their methodological limitations, the before-
and-after studies and the controlled clinical trials had
to be considered with caution as they had a certain
selection bias for not presenting any randomization
method 30 or control groups 31 32, which could have
affected the VRT evidence obtained.
Most trials aimed at a non-immersive use 22 23 24 2 5 26
28 29 30 31 32 of VR, and only 1 was fully-immersive 27 .
All of them showed a statistically signiicant improve-
ment with VRT p<0.05 in balance control 22 26 28 30
32 , motor function 25 26 29 31 32, and psychological
aspects 2 7. The effect size of the interventions 23 2 6 27
was determined to be between medium and large.
Regarding the type of VRT, although in some con-
trolled clinical trials 23 24 25 29 30 no statistically sig-
niicant differences were observed between the VRT +
CT intervention compared to the CT, signiicant
improvements were found in the IG in different func-
tional parameters Table 6. Additionally, in the
remaining 4 trials 22 2 6 27 2 8, statistically signiicant
differences were observed in the IG that were reflected
in a greater improvement compared to the CG. The
sum of both results suggests that VRT can be an
important adjunct/complementary instrument for CT
when considering the beneits derived from the differ-
ent protocols, particularly in terms of balance control,
motor function, and patients’ moods.
Moreover, even though the evidence was method-
ologically limited, it could be added that the before-
and-after studies 31 32 also showed positive effects of
VRT when applied individually to improve LL motor
function and driving skills, which speaks to the conve-
nience of using VRT along with CT.
Furthermore, the indings 23 25 2 9 32 suggest consid-
ering VRT as a complement to CT that can be used at
home and not just in a hospital setting to extend the
time of therapy sessions and to monitor and/or main-
tain the results achieved after rehabilitation. In this
regard, the need for future studies to compare the
effects of VRT in both settings was highlighted.
Comparatively, 4 controlled clinical trials 22 24 29 30
underlined that it was not possible to visualize the
effect of VRT separately, because it was applied
together with CT. Thus, a proposal was made to con-
duct studies with the same methodological quality
focused on interventions centered on VRT alone, with
a broader and more diverse sample of SCI patients.
Ecacy of virtual reality therapy
Most studies showed a good level of evidence for the
use of VR technology applied to the rehabilitation of
SCI patients based on a detailed description of its
application, movements made, and patient interaction
with the virtual environment. There was only one
exception, where information was inferred from the
system used 29 .
Non-immersive VR was the most commonly imple-
mented type of VR based on games with a scoring
system and a set duration, whose level of dificulty
was determined based on the progress recorded 22 2 3
25 26 28 29 30 32.
Other study 3 2 mentioned that the type of VR used
was augmented reality, which would require virtual
objects to be projected onto real world surfaces.
However, when the VR technological description was
analyzed, it was clear that they had used a non-immer-
sive system that displayed the virtual environment
and objects on a screen.
It was interesting to see how fully-immersive VR tech-
nology 27 used to study patients’ moods only focused
on projecting videos of real landscapes without any
means of interaction with the virtual environment,
given the technological capabilities of the device.
Although an improvement was achieved in patients'
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 107
psycho-emotional health, it will be necessary to gather
more evidence on the effects of fully-immersive tech-
nology on VRT, related with physiotherapy and occupa-
tional therapy exercises, to analyze and determine the
impact of this type of VR on the rehabilitation of SCI
patients. Despite the technological differences inherent
to each VR technology, such as the degree of immersiv-
ity and sensorimotor interaction, previous literature
has shown different beneits of the use of the full-im-
mersive VR and some of them points that full-immer-
sive VR outperforms non-immersive 33 34 35.
Although all the interventions applied different
immersive and non-immersive VR, some signiicant
beneits were identiied that can be generalized as fol-
lows: VR stimulated a wide set of functional move-
ments similar to those of the real world; it promoted
independence and self-conidence; it improved psy-
cho- emotional health; it increased patient motivation
and engagement with the rehabilitation process; and it
promoted VRT with no side effects. Such evidence
made it possible to conirm the potential use of VR
technology as an effective tool for rehabilitation of SCI
patients.
The eficacy of VR was conirmed based on a number
of indicators reported by the studies. Firstly, there was
positive feedback visual and auditory about thera-
peutic sessions designed around games that included a
scoring system to help patients come up with new
self-improvement strategies within certain time-
frames and levels of dificulty established by the
devices and/or adjusted by therapists, which made it
possible to follow-up on the progress made.
In this regard, it was observed that the level of difi-
culty in each round prompted patients to make speciic
movements in an intensive and repetitive manner,
which stimulated the subsequent recovery of motor
function as a result of triggering neuroplasticity mostly
in the motor cortex of the brain 23 24 26 28 2 9 32.
Secondly, real-time visual feedback was another indi-
cator of eficacy of VR environments for motor func-
tion recovery 26 28 29; that is, there was visual feed-
back of the patient’s proper movement execution
within the game’s virtual environment with the use of
an avatar through activation of certain areas of the
motor cortex, leading to improved recovery 32. There
was also activation of the mirror neuron system and
motor cortex of the brain by enabling recovery in spa-
tial orientation and balance 30 . Furthermore, visualiz-
ing the patient’s movements in real-time made by the
avatar through mirror vision produced a feeling of
control and realism with a similar positive effect on
motor function 2 3.
Thirdly, given the importance of patients’ motivation
as an indicator of eficacy, it is interesting to see that
this factor was assessed only by 3 studies 23 29 3 2,
with high levels of satisfaction and motivation
achieved during VRT. However, even when such an
evaluation was not considered, another study 26 indi-
cated that patients showed a high level of interest and
enthusiasm towards VRT, and another one 30 observed
that patients were open to develop new self-improve-
ment strategies as a result of their experience with
VRT. In summary, given the limited evidence on the
level of patient acceptance of VRT, it is suggested that
future research should include instruments to evalu-
ate this aspect as well.
The indings from the above-mentioned evaluations
showed that patients’ satisfaction and motivation with
VRT promoted a higher level of commitment, adher-
ence, active engagement, and dedication to the reha-
bilitation process. Personal motivation due to VR was
promoted by feelings of increased curiosity, self-coni-
dence, self-driven exploration, and imagination which
led to a greater enjoyment of the CT in addition to
functional improvements 23 2 9 32. Moreover, social
motivation that led to the development of self-im-
provement and self-esteem were promoted through
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
108
competition as a result of the social interaction of
patients based on the level of dificulty and scoring of
VR games 23 29.
As it was conirmed in other studies 33 34 36, these
key elements are not induced by CT, which limits their
level of effectiveness by showing low level of atten-
dance and adherence to the training exercises, thus
limiting the level of intensity necessary to achieve
patient recovery.
This increase in motivation may be related to the
influence of the video games used in VRT with a scor-
ing and reward system positive feedback 29 3 4, and
that it decreases the perception of effort 37 , which
boost active patient participation and therefore
increases adherence and commitment to the rehabili-
tation therapy.
In addition, some studies 35 38 have conirmed that
VRT promotes a deep motivation in patients, which
improves their subjective initiative and commitment
to actively complete various rehabilitation exercises,
thus creating a virtuous circle that improves their
func t io n a l recovery.
Some studies included in the SR underlined that the
VRT was the most effective tool for improving neuro-
plasticity and subsequent recovery of motor function
in SCI patients through intense and repetitive task-ori-
ented practice by increasing exercise therapy time
expressed as time dedicated to practice dosage com-
pared to CT 36 38, which may enhance functional
recovery 23 26 29 30 32 34. However, it is important to
point out that other studies report that the evidence of
neuroplasticity as a result of training in VR is currently
modest and more research it is needed 38. Also, it
should be noted that the relation between dosage and
achieving functional recovery is currently an unsolved
issue in rehabilitation studies 30 32 36, where the need
for further evidence is highlighted.
There is some additional evidence resulting from the
authors’ perceptions during the interventions. For
instance, when patients immersed themselves in VRT
game activities, they forgot about certain fears that
could have affected their performance vis-à-vis the
objectives of the CT activities 26 . The projected images
had a positive impact on the patients’ moods and
reduced the perception of pain from the SCI 2 7, which
reafirmed the convenience of using VRT in conjunc-
tion with CT 28 30.
The importance of the familiarization process
between the patient and the VR technology is a key
element to achieve the objectives of the rehabilitation
programs as it allows the patients to be engaged with
the VRT and to perform the training exercises in a
more effective way, thus promoting their active partic-
ipation and motivation. In this regard, some studies
have highlighted 26 28 33 37 the limitations of com-
mercial VR systems to it the needs of SCI patients,
since these are designed to be used by people without
motor or cognitive impairments. Additionally, previ-
ous studies 34 38 39 have conirmed the importance of
patients perceiving a greater immersion in the virtual
environment rather than in the real world, which is
related to the software and hardware characteristics.
Therefore, it is necessary that research teams seek to
adapt existing devices to provide better grip and
manipulation of the peripherals of VR systems 29 3 3,
or still better to design new devices that allow an
improved handling and capture of the movements
made by patients according to their motor and cogni-
tive skills, along with an appropriate calibration
according to their neurological conditions 2 9, which
will increasing their interaction with the virtual envi-
ronment, thus a better immersive experience.
On the other hand, another important element that
allows patient familiarization is the sense of presence,
which is related to the patients' subjective experience
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 109
of feeling inside the virtual environment and is able to
active brain mechanisms underlying sensorimotor
integration as well cerebral networks regulating
focused attention promoting patients to perform reha-
bilitation programs and patients’ movement recovery
34 37. Since this also depends on the characteristics of
the VR system itself 37, it is important that the games
are able to imitate both in execution and visually the
task-oriented activities and the virtual scenario, as
well as to increase the sensory feedback through the
peripherals, which allows a higher level of realism
when interacting with 3D objects in real-time, for
instance the realistic haptic feedback achieved by the
CyberGlove compared to the simple feedback offered
by most commercial consoles 24 33. In addition, as
already pointed out by some studies included in this
review, the patient's embodiment in the virtual avatar,
either in one part irst person or the whole body
third person, has a key role in developing a sense of
presence in the virtual environment, as it allows the
sensation that the actions performed belong to the
patient 3 4. In this sense the non-commercial devices
achieved better results, especially TOyRA system 23 2 5
by achieving an avatar based on the patients’ anthro-
pometric data.
In addition, it would be important to include induc-
tion training programs 30 32 that make it possible to be
familiar with the VR system and interact with greater
conidence within the virtual environment. Therefore,
all the elements that allow familiarization increase the
acceptance of the system by the patient as he/she feels
that real world movements are performed within the
virtual environment, which allows to obtain adequate
functional improvements by providing a better trans-
fer of skills to the real world and open the possibility of
continuing rehabilitation programs at home 23 33.
Fourthly, another eficacy indicator was the ability to
gradually reduce the help required from the therapist
as therapy progressed, leading to more patient inde-
pendence to choose the VRT activities designed in
accordance with the rehabilitation goals 23 2 9.
Nevertheless, some authors reported that VRT had
been more effective with the help of a therapist 32 .
Fifthly, potential home-based rehabilitation and tel-
erehabilitation were other key eficacy indicators of
the use of VR technology based on commercial con-
soles and other devices. Having more intuitive, smaller
sized, home-based systems could possibly increase
the amount of time devoted to rehabilitation following
therapy administered at the hospital or rehabilitation
center. In this context, it should be stressed 23 that
patients stated their interest in using the virtual sys-
tem at home and would suggest its use to other
patients with the aim of potentially creating an online
gaming network to promote more socializing among
patients and to extend therapy time.
Moreover, home-based VR rehabilitation could have a
positive impact on reducing costs, time, effort, and
travel of patients to the clinics, with systems being
adapted to patients’ needs, particularly those with a
high SCI level 29 32. Based on the aforesaid, it would
be necessary to have data capture systems imbedded
in the consoles or in future rehabilitation dedicated
devices that are capable of sending information of the
activities performed at home to the therapist for anal-
ysis 25 32.
It is important to emphasize that some features of the
VR devices posed some potential limitations to the efi-
cacy of VRT, for instance: the virtual environment used
by the TOyRA system did not represent execution of
ADL in a realistic fashion 23 ; the commercial consoles
or peripherals used in the interventions were relatively
obsolete given the ongoing technological advances
seeking to make VR more eficient and easy to use in
rehabilitation; and the consoles or peripherals could
not be easily modiied black box, thus preventing
adaptation to patients’ functional needs 22 26 28 29 30.
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
110
It should be noted that only one paper reported hav-
ing used a graphic engine Unity 3D 3 2, given its rele-
vance to the creation of virtual environments and the
effect of VR on rehabilitation. Using a graphic engine
implied a signiicant investment in terms of time and
practice in order to create an appealing virtual envi-
ronment where the patient can properly interact.
Therapists collaborated on this design effort 23 2 5 32.
Finally, this SR identiied some evidence of the
impact of VRT in other neurological disorders, which
conirms some of the indings for SCI, since the
impaired motor function is one of its common conse-
quences. For instance, some reviews have been identi-
ied concerning the use of VR technology applied to
Stroke 38 39 40 41, Parkinson’s Disease 35 42 43, Mul-
tiple Sclerosis 37 44 , Cerebral Palsy 45 and Traumatic
Brain Injury 46, which have reported positive effects
of VRT improving balance control 35 4 0 42 43 44 45 46 ,
UL or LL motor function 37 38 39 40 41 45, gait 35 40 42
43 44 46 and cognitive function 3 7 42 4 6. A systematic
review 47 showed positive impacts in the treatment of
phantom limb pain due to a greater immersive experi-
ence based on the use of the mirror therapy which
induces the perception that the amputated limb is
performing the tasks. However, the authors are incon-
clusive regarding the eficacy of VR and Augmented
Reality therapy and continues to need further research
with higher quality evidence.
As is the case of the interventions with SCI patients,
the role of VR as rehabilitation tool in these neurologi-
cal disorders is still under discussion, although some
studies reported positive results when VR was used as
a complementary therapy which improved ADL per-
formance and quality of life. These studies provided
evidence points toward the advantages of increased
motivation, conidence, engagement, and increase the
intensity of movement based in repetitive and task-ori-
ented with multisensory feedback which is needed for
promoting neuroplasticity 35 37 39 40 43 45 46.
These results align with the main indings on the use
of TRV in patients with SCI and for future development
could be important to follow research on how the VR
devices had been designed to these pathologies,
including the greater use of VR full immersive and
multisensory feedback 33.
In this regard, an interesting feature showed in a
study applied to Stroke 40 was the introduction of a
speciic type of rehabilitation visual feedback named
“virtual teacher”, which can be displayed during
every task repetition and that shows the correct exe-
cution movement of the training exercise so that the
patient can imitate it allowing real-time visual com-
parison between a patient’s execution and the virtual
teacher’s execution of a movement. The incorpora-
tion of this characteristic into the VR systems for SCI
could improve the motor performance quality pro-
moting motor adaptation via supervised learning
mechanism.
Limitations and future work
of the systematic review
One of the main limitations was not having a larger
number of papers providing evidence on the use of
augmented reality and fully-immersive VR technology
as a rehabilitation tool.
Patient sample heterogeneity as well as the applica-
tion of different types of VR technology and VRT pro-
tocols made it impossible to generalize the results and
applied therapies, and since this SR was guided by the
Cochrane recommendations 1 4 , it was deemed advis-
able not to do a meta-analysis.
Moreover, no controlled clinical trials were found to
focus on the use of VRT individually in the IG com-
pared only with the CT. This could be based on the
fact that there is not much research on this, and it was
not possible to access a more specialized, fee-based
database.
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 111
The authors of this SR consider it necessary to update
this SR in the future to largely include blinded, ran-
domized, controlled clinical trials with long-term fol-
low-up to reduce the risk of bias and follow-up on the
sustained effects of the intervention.
CONCLUSIONS
Given the evidence obtained from the papers included
in the review, this SR concludes that non-immersive
VR technology is an effective tool for use in neurore-
habilitation as a complement to CT. It has positive
effects by promoting motivation, self-conidence,
commitment, and active engagement of patients, lead-
ing to improvements in motor function, and balance
control, both in a clinical setting and at home, and it
also increases rehabilitation time. No side effects were
observed throughout the interventions.
Positive effects of VRT were identiied when it was
applied alone, although more evidence is needed to
determine its contribution. Furthermore, there were
psycho-emotional beneits reported with a decrease in
depression in SCI patients when fully-immersive VR
was used, although more research is needed to con-
clude its level of eficacy as a complementary tool to CT.
However, the high cost and the complexity of the new
VR technology is a key limitation to extend the use for
rehabilitation which may explain why the therapy
based on video games consoles and non-immersion
VR systems are playing an important role in rehabilita-
tion programs even considering that these devices are
not suitable to the needs of the SCI patients.
This SR suggest further development of VR systems
customized to the motor and cognitive skills of SCI
patients that achieves increased immersion with a
higher level of realism of the rehabilitation activi-
ties, multisensory stimuli, and patient interaction,
while trying to keep low-cost in order to increase
accessibility.
AUTHOR CONTRIBUTIONS
Both authors formulate and designed the systematic
review; collected, selected, and extracted the data;
assessed the risk of bias and methodological quality of
included papers, and summarized the results. B.A.O.S.
drafted the irst version of the manuscript. Both
authors reviewed the manuscript in depth and wrote
the inal version. Both authors analyzed and included
the reviewers suggested comments.
REVISTA MEXICANA DE INGENIERÍA BIOMÉDICA | Vol. 42 | No. 2 | MAY - AUGUST 2 021
112
REFERENCES
[1] World Health Organization. International perspectives on spina l
cord injur y Inter net. Geneva: WHO; 2013. Available f rom: ht t ps://
www.who.int/disabilities/policies/spinal_cord_injur y/en/
[2] Latham R. Lesión de la médula espinal: Esperanza en la
investigación Internet. Bethesda: National Inst itute of
Neurological Disorders and Stroke; 2005. Span ish. Available from:
https://espanol.ninds.nih.gov/trastornos/lesion_de _la_medula_
espinal.htm#:~:text=Las%20personas%20con%20lesiones%20de%20
la%20m%C3%A9dula%20e spinal%20tiene n%20
un,anticoagulante%20como%20medida%20de%20
prevenci%C3%B3n
[3] Tortora GJ, Derric kson B. Principles of Anatomy a nd Physiology.
13th edition. Hoboken NJ: J. Wiley & Sons; 2012.
[4] Strassburguer-Lona K, Herná ndez-Porras Y, Barquín Santos E.
Lesión Medular: guía para el manejo del paciente con LM c rónica
Internet. Madrid: Aspayam-Madrid; 2013. Spanish. Available from:
https://www.codem.es/guias/lesion-medular-guia-para-manejo-
integral-del-paciente-con-lm-cronica
[5] Northwestern Medicine. Spinal Cord I njury Internet Chicago:
Northwestern Medicine; 2020. Available from: htt ps://ww w.nm.org/
conditions-and-care-areas/orthopaedics/acute-spinal-cord-injury
[6] Huete- García A, Díaz-Velázquez E. Aná lisis sobre la lesión medular
en España Internet. Madrid: Aspaym; 2012. Available f rom: http://
riberdi s.cedd. net /h andle/11181/5510
[7] National In stitute of Child Hea lth and Human Development. How is
SCI diagnosed? Internet. Bethesda: NICHD; 2016. Available from:
https://www.nichd.nih.gov/health/topics/spinalinjury/conditioninfo/
diagnosed
[8] Pérez-Estudillo C A, Sánc hez-Alonso D, López-Meraz M L, Morgado-
Valle C, et. al. Aplicac iones terapéuticas para la lesión de médula
espinal. Eneurobiología. 2018; 921:141118. Spanish.
[9] Navarrete JM. La rea lidad virtual como arma terapéutica en
rehabil itación. Rehabil Integral. 2010;51:40-45. Spanish.
[10] Navarro A raujo GMK. Realidad virtual en la terapia ísica
dissert ation. Lima: Universidad Inca Garci laso de la Vega; 2017.
Spanish.
[11] Urr útia G, Bon il l X. PRISM A declaration: A proposal to improve the
publication of systemat ic reviews and meta-a nalyses. Med Clin
Internet. 2010; 13511:507-511. Available from:
https://doi.org/10.1016/j. medc li.2010.01.015
[12] Moher D, Liberati A, Tetzlaff J, et al. Preferred Reporting Items for
Systematic Reviews a nd Meta-Ana lyses: The PRISMA Statement.
PLoS Med I nternet. 2009; 67:e1000097. Available from:
https://doi.org/10.1371/journal.pmed.1000097
[13] Liberati A, A ltman DG, Tetzlaff J, Mulrow C, et. al. The PRISMA
statement for reporting systemat ic reviews and meta-a nalyses of
studies t hat evaluate healthc are interventions: explanation and
elaboration. BMJ Internet. 2009;339:b2700. Available from:
https://doi.org/10.1136/bmj.b2700
[14] Centro Cochrane Iberoa mericano. Manual Coch rane de Rev isiones
Sistemáticas de Intervenciones, versión 5.1.0 Internet. Barcelona:
Centro Cochrane Iberoa mericano; 2012. Available from: http://www.
cochrane.es/?q=es/node/269
[15] Silvera Iturrioz C. Algunas or ientaciones prácticas para la búsqueda
de información en LI LACS y PUBMED I nternet. Montevideo:
e-prints in library & information science; 2013. Available from:
http://eprints.rclis.org/24012
[16] Clar ivate Analytics. Web of Science Core Collection Help Internet.
Web of Knowledge; 2020. Available from: https://images.
webofknowledge.com/WOKRS533JR18/help/WOS/hp_database.html
[17] Nat ional Center for Biotech nology Informat ion. PubMed User Guide
Internet. NCBI; 2020. Available from: https://pubmed.ncbi.nlm .nih.
gov/help
[18] BIREM E. Tutor ial de búsqueda LILACS Internet. BIREME; 2019.
Available from: https://wiki.bireme.org/es/index.php/Tutorial_
de_b%C3%BAsqueda_L ILACS
[19] Zurita-Cr uz JN, Má rquez-González H, Miranda-Novales G, Villasís-
Keever MA. Estudios exper imenta les: diseños de invest igación para
la evaluación de inter venciones en la clínica. Rev A lerg Mex
Internet. 2018;652:178-186. Spanish. Available f rom:
https://doi.org/10.29262/ram .v65i2.376
[20] PEDro. PEDro scale Internet. Physiotherapy Ev idence Database;
1999. Available from: https://pedro.org.au/english/resources/pedro-
scale
[21] Nat ional Institute of Health. St udy Qual ity Assessment Tools
Internet. NIH. Available from: https://www.nhlbi.nih.gov/health-
topics/study-quality-assessment-tools
[22] D'Addio G, Iuppariello L, Ga llo F, Bifulco P, et al. Comparison
between clinical and instrumental assessing using Wii F it System
on balance control. 2014 IEEE International Sy mposium on Medical
Measurements and Appl ications MeMeA IEEE MeMeA I nternet.
Lisboa: IEEE: 2014:1-5. Available from:
https://doi.org/10.1109/MeMeA.2014.6860124
[23] Dimbwadyo-Terrer I, Gil-Agudo A, Segura-Fragoso A, de los Reyes-
Guzmán A, et. al. Effectiveness of the Virtual Reality System Toyra
on Upper Limb Function in People with Tetraplegia: A pilot
Randomized Clinica l Trial. Biomed Res Int Internet.
2016;20166:6397828. Available from:
https://doi.org/10.1155/2016/6397828
[24] Di mbwadyo-Terrer I, T rincado-Alonso F, de los Reyes-Guzmá n A,
Aznar MA, et. al. Upper li mb rehabi litation after spinal cord injury:
a treatment based on a dat a glove and a n immersive vir tual realit y
environ ment. Disabil Rehabil Assist Tech nol Inter net.
2016;116:462-467. Available from:
https://doi.org/10.3109/17483107.2015.1027293
[25] Gil-Ag udo A, Dimbwadyo-Terrer I, Peña sco-Ma rtin B, de los Reyes-
Guzmán A, et al. Experiencia clínica de la aplicación del sistema de
realidad TOyRA en la neuro-rehabilitación de pac ientes con lesión
medular. Rehabilitación Internet. 2012;461:41-48. Spanish.
Available from: https://doi.org/10.1016/j.rh .2011.10.005
[26] Khurana M, Walia S, Noohu M. Study on the Effectiveness of Virtual
Reality Game-Based Training on Balance and Functional
Performance in Individuals wit h Paraplegia. Top Spinal Cord Inj
Rehabil Internet. 2017;233:263-270. Available from:
https://doi.org/10.1310/sci16-00003
B. A. Orsatti-Sánchez et al. Efficacy of Vir tual Reality in Neuror ehabilitation of Spinal C ord Injury Patients: A Sys tematic Review 113
[27] Lakhani A, Martin K, Gray L, Mallison J, et. al. What is the impac t of
engaging with natural environments delivered v ia virtual realit y on
the psycho-emotional health of people w ith spinal cord inju ry
receiving rehabilitation in hospital? Findings from a pilot
randomized control led trial. Arch Phys Med Rehabil Internet.
20 20; 10 1 9:15 32-15 40. A v a ilabl e f rom :
https://doi.or g/10.1016/j .apm r.2020.05.013
[28] Tak S, Choi W, Lee S. Game-Based Vir tual Reality Training Improves
Sitting Balance after Spinal Cord Injur y: A Single-Blinded,
Randomized Controlled Tr ial. J Med Sci Tech nol Inter net.
2015;56:53-59. Availab le f rom:
https://doi.org/10.12659/MST.894514
[29] Prasad S, Aikat R, Labani S, Khanna N. Efic acy of Virtual Realit y in
Upper Limb Rehabilitation in Patients with Spinal Cord Injury: A
Pilot Randomized Controlled Trial. Asian Spine J Internet.
2018;125:927-93 4. Avai lable f rom:
https://doi.o rg/10.31616/asj.2018.12.5.927
[30] Sengupt a M, Gupta A, K hanna M, Krishnan UKR, et al. Role of
Virtual Reality in Balance Trai ning i n Patients with Spinal Cord
Injury: A Prospective Comparative Pre -Post Study. Asia n Spine J
Internet. 2019;141:51-58. Available from:
https://doi.org/10.31616/asj.2019.0013
[31] Wen-Hsu S, Ting-Ying C, Wen-Wei T, Cheng H, Jin-Jong C. The effect
of virtual reality-enhanced driving protocol in patients following
spinal cord injur y. J Chin Med Assoc Internet. 2012;7511:600-
605. Available from: https://doi.org/10.1016/j.jcma.2012.08.004
[32] Villiger M, Liviero J, Awai L, Stoop R, et. al. Home-Ba sed Vir tual
Reality-Augmented Training Improves Lower Limb Muscle
Strength, Balance, and Functional Mobi lity following Chronic
Incomplete Spinal Cord Injury. Front Neurol Internet. 2017;8 :635.
Available from: https://doi.org/10.3389/fneur.2017.00635
[33] Massetti T, Dias-da-Silva T, Brusque Crocetta T, Guar nieri R, et. al.
The Clinical Utility of Virtual Reality in Neurorehabilitation: A
Systematic Review. J Cent Nerv Syst Dis Internet. 2018;10:1-18.
Available from: https://doi.org/10.1177/1179573518813541
[34] Tieri G, Morone G, Paolucci S, Iosa M. Virtual real ity in cognitive
and motor rehabilitat ion: facts, iction and fal lacies. E xper t Rev
Med Devices Inter net. 2018; 152:107-117. Available f rom:
https://doi.org/10.1080/17434440.2018.1425613
[35] Cheng L, Kejimu S, Feng ling D, Xiaoqin L, et. al. Ef fects of v irtual
reality rehabilitation t rain ing on ga it and balance in patients w ith
Parkinson’s disease: A systematic review. PLoS One Internet.
2019; 1411:e0224819. Available from:
https://doi.org/10.1371/journal.pone.0224819
[36] Kwakkel G. I mpact of intensity of practice a fter st roke: Issues for
consideration. Disabil Rehabil. 20 06;2813-14:823-830. Available
from: ht tps://doi.o rg/10.1080/09638280500534861
[37] Grazia Maggio M, Russo M, Foti Cuzzola M, Destro M, et. al. Virtual
reality in multiple sclerosis rehabilitation: A review on cog nitive
and motor outcomes. J Clin Neu rosci Internet. 2019;65:106-111.
Available from: https://doi.org/10.1016/j.joc n.2019.03.017
[38] Laver KE, Lange B, George S, Deutsch JE, et al. Vi rtual Reality for
stroke rehabilitation Review. Cochrane Database Syst Rev
I nte rn et. 2017;1111:CD 00 8349. Ava ilable f rom:
https://doi.org/10.1002/14651858.CD008349.pub4
[39] Sin HH, Lee GC. Additional vi rtua l reality trai ning using Xbox
Kinect in stroke survivors with hemiplegia. Am J Phys Med Rehabil
Internet. 2013;9210:871-880. Available from:
https://doi.org/10.1097/PHM.0b013e3182a38e40
[40] Kiper P, Luque-Moreno C, Pernice S, Maistrello L, et al. Functiona l
changes in the lower extrem ity af ter non-immersive virtual real ity
and physiotherapy following stroke. J Rehabil Med Internet.
2020;5211:jrm00122. Available f rom:
https://doi.or g/10.2340/16501977-2763
[41] Norouzi- Gheidari N, Herna ndez A, Archambau lt PS, Hig gins J, et al.
Feasibility, Safety and Eficacy of a Virtua l Reality Exergame
System to Supplement Upper Extremit y Rehabilitation Post-Stroke:
A Pilot Randomized Clinical T rial and Proof of Principle. Int J
Environ Res Public Health Internet. 2019;171:113. Available
from: ht tps://doi.org/10.3390/ije rph17010113
[42] Triegaardt J, Ha n TS, Sada C, Sharma S, et al. The role of virtual
reality on outcomes in rehabilitation of Pa rkinson’s disease: meta-
analysis and systematic review in 1031 participants. Neurol Sci.
Internet. 2020;413:529-536. Available f rom:
https://doi.org/10.1007/s10072-019-04144-3
[43] Feng H, Li C, Liu J, Wang L , et. al. Virtua l Reality Rehabilitation
Versus Conventional Physical Therapy for Improving Bala nce and
Gait in Pa rkinson’s Disease Patients: A Randomized Controlled
Trial. Med Sci Mon it Inter net. 2019;25:4186-4192. Available from:
https://doi.or g/10.12659/MS M.916455
[44] Casuso-Holgado MJ, Martín-Valero R, Carazo AF, Medrano-Sánc hez
EM, et al. Effect iveness of v irtual reality training for balance and
gait rehabilitat ion in people with mult iple sclerosis: a systematic
review and meta-analysis. Clin Rehabil Internet. 2018;329:1220-
1234. Available from: https://doi.o rg/10.1177/0269215518768084
[45] Ravi DK, Kumar N, Si nghi P. Effectiveness of virtual reality
rehabil itation for children and adolescents with cerebral palsy: an
updated evidence-based systematic review. Physiotherapy
Internet. 2017;1033:245-258. Available from:
https://doi.org/10.1016/j.physio.2016.08.004
[46] Aida J, Chau B, Dunn J. Immersive virtual reality i n traumatic brai n
injury rehabilitation: A literature review. NeuroRehabilitation
Internet. 2018;424:441-448. Available from:
https://doi.o rg/10.3233/NRE-172361
[47] Dunn J, Yeo E, Moghaddampour P, et al. Virtual and augmented
reality in the treatment of pha ntom limb pain: A literature review.
NeuroRehabilitation Internet. 2017;404:595-601. Available from:
https://doi.o rg/10.3233/N RE-171447