E ficacy o a physical ehabili a ion p og am
using i ual eali y in pa ien s wi h ch onic
endinopa hy: A andomized con olled ial
p o ocol (Vi Tendon-Rehab)
Da id Lucena-An on
1,2
, Juan G Dominguez-Rome o
1
,
Juan C Chacon-Ba ba
1
, Ma ía José San i-Cano
1,2
, Ca los Luque-Mo eno
3
and Jose A Mo al-Munoz
1,2,4
Abs ac
Objec i es: To analyze he e ficacy o a i ual eali y (VR)-based ehabili a ion p og am in people wi h ch onic endinopa hy
(CT) on pain, muscle ac i a ion pa e n, ange o mo ion, muscle s eng h, kinesiophobia, physical unc ion, quali y o li e,
and use sa is ac ion compa ed o a con ol g oup. In addi ion, he ela ionship be ween hese a iables and he clinical
p ofile o his popula ion will be analyzed.
Design: A 12-week, single-blind, low- isk, andomized con olled ial.
Me hods: Six y pa ien s diagnosed wi h CT will be en olled and andomly assigned o wo g oups. The con ol g oup will
ecei e a physical exe cise p og am wi hou VR suppo (45 min), whe eas he expe imen al g oup will ecei e an addi ional
15-min in e en ion h ough a physical exe cise p og am deli e ed by VR. Bo h g oups will ecei e h ee sessions pe week,
and he ou comes will be collec ed a baseline, a e 12 weeks, and a he 24-week ollow-up. S a ified g oups will be es ab-
lished acco ding o endinopa hy loca ion (shoulde o a o cu , elbow, pa ella, and Achilles endon). S a is ical analyses
using SPSS .24 will include desc ip i e analysis, s a ified analysis by endinopa hy loca ion, no mali y checks, in ag oup
and in e g oup di e ences, e ec sizes, and a iable ela ionships.
Discussion: The esul s o his p ojec may ha e a significan impac on he knowledge o using VR in endinopa hy man-
agemen , unde s anding how he ou comes a e ela ed, and cha ac e izing he clinical p ofiles o he popula ion diagnosed
wi h CT. I hese esul s a e confi med, VR would be clinically use ul o he ea men o hese condi ions.
T ial egis a ion numbe : NCT06056440.
Keywo ds
Exe cise, physical he apy, ehabili a ion, endinopa hy, i ual eali y
Submission da e: 12 June 2024; Accep ance da e: 17 Oc obe 2024
1
Depa men o Nu sing and Physio he apy, Uni e si y o Cadiz, Cadiz, Spain
2
Biomedical Resea ch and Inno a ion Ins i u e o Cadiz (INiBICA), Cadiz,
Spain
3
Ins i u o de Biomedicina de Se illa (IBIS), Depa amen o de Fisio e apia,
Uni e sidad de Se illa, Se ille, Spain
4
Obse a o y o Pain, G ünen hal Founda ion-Uni e si y o Cadiz, Cadiz, Spain
Co esponding au ho :
Da id Lucena-An on, Nu sing and Physio he apy, Uni e si y o Cadiz, Cadiz,
Spain; Biomedical Resea ch and Inno a ion Ins i u e o Cadiz (INiBICA),
Cadiz, Spain.
Email: da [email protected]
C ea i e Commons NonComme cial-NoDe i s CC BY-NC-ND: This a icle is dis ibu ed unde he e ms o he C ea i e Commons A ibu ion-
NoDe i s 4.0 License (h ps://c ea i ecommons.o g/licenses/by-nc-nd/4.0/) which pe mi s any use, ep oduc ion and dis ibu ion o he wo k as
published wi hou adap a ion o al e a ion, p o ided he o iginal wo k is a ibu ed as specified on he SAGE and Open Access page (h ps://us.sagepub.com/
en-us/nam/open-access-a -sage).
Resea ch P o ocol
DIGITAL HEALTH
Volume 11: 1–11
© The Au ho (s) 2025
A icle euse guidelines:
sagepub.com/jou nals-pe missions
DOI: 10.1177/20552076241297043
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In oduc ion
Backg ound and a ionale
Tendon o e use inju ies ( endinopa hy) cause pain, dec eased
exe cise ole ance, and educed endon unc ion in he uppe
and lowe limbs.
1
The mos common endinopa hies include
shoulde o a o cu endinopa hy, epicondyli is/epi ochlei is,
ochan e i is, pa ella endinopa hy, and Achilles endinopa hy.
2
Tendinopa hies cause significan mo bidi y and disabili y ha
may pe sis o se e al mon hs, despi e adequa e ea men .
3
Ch onic endinopa hies (CT), wi h symp oms p esen o mo e
han six weeks, ha e a significan impac on pa ien s’abili y o
pe o m hei wo k, exe cise, and/o pe o m ac i i ies o daily
li ing.
4
Al hough i is di ficul o de e mine he incidence o
his pa hology, i is es ima ed ha 30% o musculoskele al inju -
ies a e ela ed o endinopa hies and 30%–50% o endinopa hies
occu in spo s.
5
Ch onic endon- ela ed p oblems accoun o
app oxima ely 30% o all unning- ela ed inju ies, and he p e a-
lence o la e al elbow endinopa hy may be as high as 40% in
ennis playe s.
6
Addi ionally, i has ecen ly been epo ed ha CT scans a e
associa ed wi h neu ophysiological changes. Fo example,
pa ien s wi h pa ella endinopa hy ha e g ea e co ical inhib-
i ion in he quad iceps han heal hy people.
7
In addi ion o his
co ical inhibi ion, he e is also g ea e co icospinal exci abili y
compa ed o people who do no ha e CT, which ul ima ely leads
o changes in mo o con ol.
8
Gi en he high ecu ence a e o
endinopa hies, i could be conside ed ha in asymp oma ic
people wi h a his o y o pain o p e ious endon pa hology,
he p e iously induced mo o con ol changes may no ha e
esol ed, p edisposing hem o ecu ence.
9
Fu he mo e, i has
been sugges ed ha hype igilance, which e e s o an excessi e
endency o a end o pain o soma ic sensa ions o an excessi e
willingness o selec pain- ela ed in o ma ion o e o he in o -
ma ion, leading o kinesiophobia, maycon ibu e o he de elop-
men o a ha m ul cycle o ch onici y in endinopa hies.
10
Changes in he ne ous sys em a e hypo hesized o play a ole
in he induc ion o main enance o pe sis en pain in endinopa-
hy.
11
In his sense, he use o dis ac o s as a pain managemen
s a egy has ecei edconside ablea en ionin bo h expe imen al
pain and acu e and ch onic clinical pain.
12,13
Addi ionally, psy-
chological ac o sha ebeen ound obeassocia edwi h endino-
pa hy and can influence he de elopmen and main enance o
pain and disabili y, indica ing he need o indi idualized, holis-
ic assessmen o endinopa hy managemen .
14
The e o e, no el
s a egies a e needed o manage CT adequa ely, a oiding mo o
con ol and pain dis u bances and, he e o e, elapses and hei
undesi able consequences.
In his sense, i ual eali y (VR) is an in e en ion ool ha
can complemen he ehabili a ion p ocess o CT, and is
defined as a “simula ion o a eal compu e -gene a ed en i on-
men in which he subjec can in e ac wi h ce ain elemen s
wi hin a simula ed space h ough a human-machine in e -
ace.”
15
I has been used in a ious a eas, such as pain
managemen , assessmen o neu ocogni i e impai men , ain-
ing in medical echniques, and exe cise-based physical ehabili-
a ion.
16,17
Specifically, he use o VR-based physical ac i i y
p og ams has eme ged in ecen yea s as a public heal h p omo-
ion s a egy and as a mo e a ac i e al e na i e o complemen
o adi ional in e en ions ha could imp o e mo i a ion
wi hou causing physical discom o o comp omising he in eg-
i y o he use .
18
VR can suppo mo o con ol ehabili a ion in se e al ways,
asi isconside edane ec i es a egy oimp o emo o pe o m-
ance by using isual, senso y, and audi o y e ec s in i ual
en i onmen s, p omo ing he pa icipan ’s a en ion,
19
allowing
indi idualiza ion o exe cises by con olling he numbe o epe-
i ions needed, inducing neu oplas ici y
20
and mo o lea ning,
21
and inc easing neu al eo ganiza ion. Fu he mo e, VR has
been shown o influence kinesiophobia, which is an impo an
ac o in he p ognosis o CT,
14
in pa ien s wi h ch onic neck
and lowe back pain h ough g adual exposu e.
22
Conce ning
pain dis ac ion, a ecen me a-analysis confi med VR-induced
analgesia o bo h acu e and sho - e m ch onic pain in adul s
and child en.
23
VR exe s i s hypoalgesic e ec s h ough a
combina ion o a en ional dis ac ion, enhanced mul isenso y
in eg a ion,neu oplas icchanges,ac i a iono endogenousanal-
gesic sys ems, emo ional and cogni i e modula ion, imp o ed
senso imo o in eg a ion, and al e ed body ep esen a ion.
24
These mechanisms wo k oge he o educe pain pe cep ion
and imp o e he o e all pain expe ience in ch onic pain pa ien s.
None heless, he e is a lack o scien ific e idence ega d-
ing he use o VR in CT managemen . A ecen andomized
con olled ial (RCT) analyzed he e ec s o a VR-media ed
gamified exe cise p og am in people wi h shoulde impinge-
men synd omecu sing wi h o a o cu CT.They oundsig-
nifican esul s on shoulde ange o mo ion (ROM) and pain
sco es compa ed o a supe ised home exe cise p og am,
highligh ing he abili y o VR-based exe cise p og ams o
inc ease pa ien engagemen in ea men and exe cise com-
pliance.
25
Con e sely, ano he RCT explo ing he e ec s o
VR exe gaming in people wi h shoulde impingemen syn-
d ome ob ained non-significan esul s on pain, ROM, unc-
ion and ac omion-hume al dis ance compa ed wi h
con en ional exe cise. The au ho s a ibu ed he lack o sig-
nifican esul s o di e en limi a ions o he s udy, such as
he applica ion o di e en exe cises in he s udy g oups,
he limi ed sample size, and he sho ollow-up pe iod.
26
In addi ion, di e en case epo s ha e been p esen ed in a
publica ion explo ing he e ec s o VR-based in e en ions
a e hand endon epai , ob aining benefi s in p ehension
and mo o unc ion. In iew o his backg ound, he e is
s ill needed o e alua e he e ec i eness o a physical
ehabili a ion p og am ha uses VR in CT.
27
Objec i es
The main objec i e o his s udy is o analyze he e ec s o a
12-week VR-based in e en ion and a 3 weeks o
2DIGITAL HEALTH
ollow-up a e comple ion o he in e en ion p og am on
pain, ROM, s eng h, pa e n o muscle ac i a ion, kinesio-
phobia, physical unc ion, quali y o li e, and use sa is ac-
ion in people wi h CT.
The seconda y objec i es will be: i) o analyze and
cha ac e ize he clinical p ofile (pain, ROM), s eng h,
muscle ac i a ion, kinesiophobia, physical unc ion,
and quali y o li e) o he popula ion diagnosed wi h
CT; and ii) o iden i y he ela ionships be ween he ou -
comes ha de e mine he esul s ob ained. The e o e, we
hypo hesized ha a VR-based in e en ion would educe
he le el o pain and kinesiophobia, which could imp o e
ROM, s eng h, and pa e n o muscle ac i a ion, and
consequen ly, physical unc ion and quali y o li e in
people wi h CT (Figu e 1).
T ial design
This is a 12-week, single-blind, pa allel-g oup RCT p o o-
col. S anda d P o ocol I ems: Recommenda ions o
In e en ional T ials (SPIRIT 2013 S a emen s)
28
we e ol-
lowed o epo he ial p o ocol.
Me hods
Pa icipan s and he s udy se ing
S udy pa icipan s diagnosed wi h CT will be ec ui ed in he
ollowing p i a e ca e physio he apy clinics: Physio he apy
and Rehabili a ion Cen e “Modofisio”(Cádiz, Spain), and
he Physio he apy Cen e “En Buenas Manos”(Cádiz, Spain).
Inclusion c i e ia
The ollowing inclusion c i e ia will be used: (i) men and
women o e 18 yea s o age; (ii) wi h a p e ious diagnosis
o CT (shoulde o a o cu , elbow, pa ella, and Achilles)
documen ed by a medical p o essional; and (iii) symp oms
las ing longe han 6 weeks.
Clinical p o essionals esponsible o p i a e ca e
physio he apy clinics will e i y whe he he inclusion c i-
e ia a e me .
Exclusion c i e ia
The ollowing exclusion c i e ia will be conside ed: (i)
inabili y o engage in physical exe cise due o a pa ho-
logical condi ion, (ii) people who ha e unde gone endon
epai su ge y, (iii) pa ien s who ha e ecei ed exe cise
he apy in he las 3 mon hs, and (i ) pa ien s who ha e
ecei ed co icos e oid injec ion in he las 3 mon hs.
In e en ions
The pa icipan s wi h CT will be di ided in o wo g oups.
The con ol g oup will unde go a physical exe cise
p og am (45 min) wi h a equency o 3 sessions/week o
Figu e 1. Diag am o e ec ela ionships be ween ou comes.
EMG: elec omyog aphy; ROM: ange o mo ion.
Lucena-An on e al. 3
a o al du a ion o 12 weeks. The expe imen al g oup will
ecei e he same in e en ion (45 min, 3 sessions/week,
12 weeks) wi h an addi ional VR-based p og am (15 min)
in asession. The sessions will be conduc ed by a
physio he apis .
Con ol g oup. The con ol g oup will unde go an indi i-
dualized p og am based on s eng hening (iso onic, isome -
ic, and eccen ic), ene gy s o age loading, and elease
exe cises.
2
This in ol es p og ession om s eng hening
exe cises o unc ional s eng h, speed, and jumping o
h owing exe cises. The exe cise p og am will be supe -
ised and guided by a physio he apis .
Vi ual eali y p og am. The expe imen al g oup will pe o m
he in e en ion p o ided o he con ol g oup wi h an add-
i ional 15 min o specific VR in e en ion. The Me a Ques 2
de ice (Me a Pla o ms Inc.), a headse ha imme ses he
use in a ully simula ed en i onmen , will be used. To c ea e
his imme si e expe ience, VR sys ems u ilize echnology
ha engages he senses. This head-moun ed VR headse
includes high- esolu ion sc eens and mo ion acking o isu-
ally en elop he use om a fi s -pe son pe spec i e. Use s
can explo e he i ual en i onmen , na iga e h ough i , and
in e ac wi h i ual objec s o cha ac e s h ough a small
display posi ioned di ec ly in on o hei eyes, by in eg a ing
audio and ideo eedback. In addi ion, he use in e ac s wi h
he i ual en i onmen by mo ing hei uppe limbs usingcon-
olle s.
29
A so wa e specifically designed o he physical
ehabili a ion o he uppe and lowe limbs: Dynamics VR
(h ps://www.dynamics- .com/) will be used. I is a unc ional
ehabili a ion p og am ha includes easy- o-pe o m exe cises
wi h a play ul componen ha encou ages he pa ien ’scon-
inuous a en ion o he ask pe o med, ac ing as a dis ac ing
phenomenon in he ace o es ic ing ac o s o mo emen
such as ea o pain. This so wa e o e s he possibili y o
adjus ing he numbe o epe i ions and cha ac e is ics o he
exe cises, hus allowing physical ehabili a ion o be adap ed
o indi idual condi ions. Specifically, i ual he apeu ic exe -
cises will be based on games ha ocus on pain dis ac ion and
g adual exposu e o mo emen . In ela ion o he uppe - and
lowe -limb condi ions, he use in e ac s wi h a ious i ual
objec s. These games will include ac i i ies ha equi e he
pa ien o pe o m o ien ed asks in ol ing (1) on al and
la e al shoulde ele a ions, (2) in e nal and ex e nal o a ions,
(3) h ows, (4) elbow flexion and ex ension, (5) p ona ion o
he uppe limbs, (6) bending and li ing, (7) heel li s, (8) low-
impac jumps, and (9) changes in di ec ion o he lowe limbs.
To ensu e ha he VR in e en ion is accessible and com-
o able o all pa icipan s, we will implemen a aining
session wi h a g adual in oduc ion whe e pa icipan s amil-
ia ize hemsel es wi h he VR headse and so wa e. A
physio he apis will guide pa icipan s h ough he se up
and p o ide suppo h oughou he ial. This app oach is
pa icula ly impo an o olde pa icipan s and hose who
may no be amilia wi h he VR echnology.
Ou comes
Sociodemog aphic and clinical ou comes will be collec ed
a baseline, as well as he es o he ou comes ha will
also be measu ed a he end o he in e en ion (12
weeks) and a he ollow-up o 24 weeks (12 weeks a e
ending he in e en ion): pain, physical unc ion, ROM,
s eng h, pa e n o muscle ac i a ion, kinesiophobia,
quali y o li e, and sa is ac ion wi h he use o he sys em.
Sociodemog aphic and clinical da a. A s uc u ed ques ion-
nai e will be used o collec sociodemog aphic and clinical
da a ha will include he ollowing a iables: da e o endi-
nopa hy diagnosis, du a ion o symp oms since symp om
onse , p esence o o he pa hologies, p e ious su gical
in e en ions, and p e ious exe cise. The ques ionnai e
used can be ound in he Supplemen al ma e ial (File S1).
Pain. The Nume ic Pain Ra ing Scale (NPRS) measu es
pain le els. I is a subjec i e pain measu e in which he
pa ien chooses a numbe be ween 0 and 10 (11-poin
nume ic scale), showing he in ensi y o pain ha hey
belie e hey a e expe iencing. A sco e o 0 co esponds
o no pain, and a sco e o 10 co esponds o he wo s
imaginable pain.
30
Rega ding he NPRS, i canno be e al-
ua ed o s uc u al alidi y o in e nal consis ency, since i
is a single-i em measu e. In addi ion, no esea ch was ound
o examine i s c oss-cul u al alidi y.
31
Howe e , i s con-
s uc alidi y showed a high co ela ion (0.86 o 0.95)
wi h he isual analogue scale in pa ien s wi h ch onic
pain condi ions (pain > 6 mon hs).
32
Physical unc ion. The Spanish e sions o he Shoulde
Pain and Disabili y Index (SPADI),
33
Vic o ian Ins i u e
o Spo Assessmen - Pa ella Tendon (VISA-P),
34
and
Vic o ian Ins i u e o Spo Assessmen - Achilles Tendon
(VISA-A)
35
will be used o measu e physical unc ion.
The SPADI ques ionnai e e alua es disabili y and pain p o-
oked by shoulde dys unc ion and comp ises 13 i ems
ela ed o he abili y o pe o m ac i i ies o daily li ing.
Highe sco es indica e g ea e disabili y and pain.
33
I was
alida ed o he Spanish popula ion wi h musculoskele al
shoulde pain, confi ming a bidimensional s uc u e (pain
and disabili y subscales), and a co ela ion o Spea man
ho =0.752 and C onbach’sα=0.90 wi h he
quick-DASH scale.
36
The VISA-P and VISA-A ques ion-
nai es e alua e he heal h- ela ed impac o endinopa hies
based on symp oms, unc ion, and he abili y o pe o m
spo s. Highe sco es indica e be e condi ions, wi h
global sco es anging om 0 o 100. The VISA-P ques ion-
nai e demons a ed s ong alidi y, e idenced by i s high
eliabili y (ICC =0.994, C onbach α=0.885), significan
4DIGITAL HEALTH
co ela ions wi h es ablished knee scales (Kujala sco e:
Spea man ho =0.897; Cincinna i scale: Spea man ho =
0.782), and sensi i i y o clinical changes, making i a
alid and eliable ool o assessing pa ella endinopa hy
in Spanish-speaking popula ions.
37
The VISA-A ques ion-
nai e demons a ed obus alidi y wi h high eliabili y
(C onbach’sα> 0.8, ICC =0.993) and s ong co ela ion
wi h he SF-36 physical componen s (Spea man ho >
0.5). These psychome ic p ope ies sugges ha VISA-A
is a alid and eliable ins umen o assessing Achilles en-
dinopa hy in Spanish-speaking popula ions.
38
Range o mo emen . The pain- ee ac i e ROM o shoulde
abduc ion and ex e nal/in e nal o a ion, w is ex ension/
flexion, knee ex ension/flexion, and ankle plan a flexion/
do siflexion, will be measu ed using a goniome e .
39
Muscle s eng h and muscle ac i a ion pa e n. The
maximum olun a y con ac ion and muscle ac i a ion
pa e n o shoulde abduc ion and ex e nal/in e nal o a ion,
w is ex ension/flexion, knee ex ension/flexion, and ankle
plan a flexion/do siflexion will be analyzed using a dyna-
mome e
40
and elec omyog aphy (EMG),
41
espec i ely.
Kinesiophobia. The Spanish e sion o he Tampa Scale o
Kinesio obia (TSK-11) will be used. This 11-i em ques ion-
nai e e alua es he ea o mo emen and can p edic pain-
ela ed disabili y. Highe sco es indica e highe le els o
kinesiophobia, wi h global sco es anging om 0 o 52.
42
The Spanish e sion o he Tampa Scale demons a ed
good eliabili y and alidi y (con e gen and p edic i e).
I showed s ong co ela ions wi h he measu es o ca as o-
phizing, dep ession, anxie y, and unc ional s a us. These
psychome ic p ope ies sugges ha i is a alid and eli-
able ins umen o assessing pain- ela ed ea in
Spanish-speaking pa ien s.
43
Quali y o li e. The Spanish e sion o he12-i em
Sho -Fo m Heal h Su ey e sion 2 (SF-12 2) will be
used o e alua e he quali y o li e. I was alida ed o
he Spanish popula ion showing s ong co ela ions wi h
measu es o empo al and spec al pa ame e s o hea a e
a iabili y (Spea man ho > 0.5). The easibili y o i s use
o he diagnosis o s ess s a es (o e aining, bu nou ,
a igue, exhaus ion, anxie y) is sugges ed.
44
This ool
includes 12 elemen s cons i u ing i s eigh -dimensional
p ofile: physical unc ioning, physical ole, bodily pain,
gene al heal h, i ali y, social unc ioning, emo ional ole,
and men al heal h. Highe sco es indica e be e condi ions,
wi h global sco es anging om 0 o 100.
45
Use sa is ac ion. The Spanish e sion o he Consume
Repo E ec i eness Scale (CRES-4) will be used o e alu-
a e use sa is ac ion. I consis s o ou i ems ela ed o he
le el o p oblem esolu ion, emo ional le el be o e and a e
ea men , and sa is ac ion wi h he ea men . Highe sco es
indica e high le els o use sa is ac ion, wi h global sco es
anging om 0 o 300.
46
Sample size
The sample size was calcula ed o iden i y he di e ences
be ween he g oups in he measu emen scales o be adminis-
e ed. The calcula ion o he sample size was ca ied
ou using he GRANMO calcula o (Ins i u Municipal
d’In es igació Mèdica, Ba celona, Spain). Based on He on
e al.,
47
45 people in he expe imen al g oup and 45 people
in he con ol g oup we e equi ed o de ec a di e ence
equal o o g ea e han 10 uni s, wi h a common s anda d de i-
a ion o 15 in he SPADI ques ionnai e. Acco ding o Gual
e al.,
48
55 people in each g oup we e equi ed o de ec a di -
e ence equal o o g ea e han six uni s in he VISA-P ques-
ionnai e, wi h a common s anda d de ia ion o 10. Finally,
conside ing he s udy ca ied ou by De Vos e al.,
49
31
people in each g oup will be equi ed o de ec a di e ence
equal o o g ea e han 12 uni s in he VISA-A ques ionnai e,
assuming a common s anda d de ia ion o 15. In all calcula-
ions, an alpha isk o 0.05 and a be a isk o 0.2 we e accep ed
in a wo-sided con as , as well as a ollow-up loss a e o 20%.
Based on he abo e, a minimum o 120 pa icipan s (60 in each
s udy g oup) will be ec ui ed o he s udy. Consecu i e sam-
pling will be ca ied ou wi h pa ien s who a end o heal h
en i ies and mee he c i e ia desc ibed abo e.
Assignmen o in e en ions
Rega ding he andomiza ion p ocess, he Epida 3.1
p og am will be used o de e mine which g oup each
pa ien will be assigned o. Th ough i s module o assign-
ing subjec s o ea men s wi h g oups o equal size, wo
lis s o 60 andom numbe s be ween 1 and 120 will be
ob ained wi hou epe i ion, which will be used o de e -
mine he g oup o which each pa ien belongs acco ding
o hei o de o a i al. I his sample size is exceeded,
he andomiza ion p ocess will con inue o make use o
he “balanced g oups”s a egy, in which he p obabili y
o inclusion in each g oup will be in e sely p opo ional
o he numbe o people al eady in ha g oup, so ha , by
p obabili y, bo h g oups will g ow in a balanced way.
Blinding
This is a single-blind s udy. Measu emen s o he a iables
in bo h s udy g oups will be pe o med by an addi ional
esea che who is blinded o he pa icipan alloca ion. To
minimize he po en ial ans e o clinician a i udes o incli-
na ions o o agains an in e en ion o he pa icipan s,
which can lead o a bias o esul s, clinicians will be
ained o always in e ac wi h bo h s udy g oups in he
same way. In his sense, clinicians will a oid using
Lucena-An on e al. 5
language in hei ins uc ions o ad ice ha migh sugges
o pa icipan s whe he hey a e in he expe imen al o
con ol g oup, and which g oup is expec ed o espond
be e o he in e en ion.
50,51
Da a collec ion
Pa icipan s who mee he inclusion c i e ia will be scheduled
and asked o p o ide in o med consen . Once pa icipa ion is
accep ed, all pa ien s will ecei e an in o ma ion session in
which he VR-based in e en ion will be explained.
Di e en es s and ques ionnai es will be used o measu e
he s udy a iables. Measu emen s o a iables will be pe -
o med a baseline (T0) and da a will be collec ed on baseline
sociodemog aphic a iables a he end o he in e en ion (T1)
and 12 weeks a e he end o he in e en ion p og am (T2).
A clinical p o essional a he heal hca e cen e will be
esponsible o pe o ming measu emen s du ing he s udy.
To minimize pa icipan d opou , we will implemen
se e al e en ion s a egies. In his way, egula communi-
ca ion and flexible scheduling op ions o accommoda e pa -
icipan s’pe sonal and p o essional commi men s will be
ensu ed. Close con ac and appo building by he s udy
s a will u he help educe a i ion, as de eloping us
has been shown o imp o e e en ion in long- e m clinical
ials.
52
The da a collec ion p ocedu e is desc ibed in de ail in
Table 1.
S a is ical me hods
S a is ical analysis will be pe o med using he SPSS .24
s a is ical so wa e. Fi s , a desc ip i e analysis o he da a
will be ca ied ou using absolu e and ela i e equencies
and measu es o cen aliza ion and dispe sion. S a ified
analysis will be pe o med acco ding o he loca ion o en-
dinopa hy. The Kolmogo o -Smi no es will be used o
check whe he he da ase has a no mal dis ibu ion.
On he o he hand, he S uden ’s - es o pai ed samples
(in case o no mali y) o he Wilcoxon es (in case o non-
no mali y) will be used o measu e he di e ences be ween
he ini ial and pos -in e en ion sco es, and he - es o
independen samples o he U Mann-Whi ney es will be
used o check he di e ences be ween each g oup (expe i-
men al and con ol). A 95% confidence in e al will be
es ablished. Cohen’sdwill be used o de e mine e ec
size. The e ec size o 0.20 is conside ed a small e ec ,
0.5 is conside ed a medium e ec , and mo e han 0.80
will be conside ed a la ge e ec .
53
The esul s will be p e-
sen ed as he s anda d de ia ion (SD) and mean (min-max).
Finally, o analyze he ela ionships be ween physical
unc ion, quali y o li e, kinesiophobia, EMG, pain,
ROM, and s eng h, mul i a ia e s uc u al equa ion
models wi h la en a iables will be used, bo h a baseline
and du ing ollow-up.
54
These models a e powe ul ools
inc easingly used in heal h p ac ice, pa icula ly o longi u-
dinal da a analysis. They allow he examina ion o ela ion-
ships be ween cons uc s and hei e ec s o e ime,
enabling a join s udy o he di ec ional e ec s o some a i-
ables on o he s and he e olu ion o he a iables hem-
sel es. In his sense, he o al p og am du a ion will be
included as a co a ia e o con ol o i s po en ial influence
on s udy ou comes. An addi ional sensi i i y analysis will
be pe o med, including and excluding he o al ea men
du a ion as a co a ia e.
In he case o missing da a, we will use in en ion- o- ea
analysis, whe e all pa icipan s will be analyzed in he
g oups o which hey we e o iginally andomized, ega d-
less o adhe ence o he in e en ion o ollow-up, hus p e-
se ing he benefi o andomiza ion and minimizing bias
om non-compliance o d opou s. Mul iple impu a ion
Table 1. Timeline o da a collec ion.
S udy Pe iod
Selec ion Alloca ion Pos -alloca ion
Tempo a y Poin s T-1 0 T0 T1 T2
Rec ui men
Eligibili y c i e ia X
In o med consen X
Assignmen o s udy g oups X
In e en ions
Expe imen al g oup (VR) ⟺
Con ol g oup ⟺⟺⟺
Assessmen s
Baseline sociodemog aphic
a iables
X
Func ionali y X X X
Pain X X X
Rom X X X
Muscle s eng h X X X
Pa e n o muscle ac i a ion X X X
Kinesiophobia X X X
Quali y o li e X X X
Use sa is ac ion X X
T0: Baseline; T1: End o p og am in e en ion (12 weeks); T2: Follow-up a e
12 weeks o ending in e en ion.
6DIGITAL HEALTH
echniques will be used o p edic missing alues based on
he obse ed da a, gene a ing mul iple da a se s wi h di e -
en impu ed alues ha will be combined o educe bias and
inc ease he alidi y o he esul s. Sensi i i y analyses will
be conduc ed o compa e esul s be ween he comple e-case
and impu ed da ase s o ensu e ha any impac o missing
da a on he esul s is iden ified. In addi ion, a i ion ana-
lyses will be conduc ed o iden i y pa e ns o di e ences
be ween pa icipan s who d op ou and hose who comple e
he s udy, helping us o de e mine whe he d opou is
andom o ela ed o specific pa icipan cha ac e is ics
and allowing us o adjus models acco dingly.
E hics
This clinical ial has been app o ed by he E hical Commi ee
o he P o ince o Cádiz (Cádiz, Spain) (Regis e numbe :
31.23). All p ocedu es shall be pe o med in acco dance
wi h he ecommenda ions and e hical p inciples o he
Wo ld Medical Associa ion’s Helsinki Decla a ion o
E hical P inciples o Medical Resea ch on Human Subjec s
and E hical P inciples o Medical Resea ch on Human
Subjec s, he e sion o which was e o med a he 64 h
Gene al Assembly in Fo aleza, B azil, in Oc obe 2013. In
addi ion, his clinical ial was eco ded in he da abase deli -
e ed by he U.S. Na ional Lib a y o Medicine,
ClinicalT ials.go , wi h iden ifie code NCT06056440.
The Consolida ed S anda ds o Repo ing T ials
(CONSORT)
55
will be ollowed o publish he s udy’sfind-
ings in in e na ional pee - e iewed jou nals and p esen
hem a con e ences wo ldwide. Addi ionally, as pa o
ou knowledge ansla ion s a egy, we will dissemina e
he findings on ins i u ional websi es and social media,
con ac news o ganiza ions, and iden i y pa ne ins i u ions
ha a e in e es ed in he findings.
Confiden iali y
All pa icipan s will be in o med e bally and in w i ing abou
he p ocedu e ha is going o be ca ied ou , and will sign an
in o med consen documen o pa icipa e be o e joining ou
s udy. This documen s a es ha hey ha e ead and unde -
s ood he in o ma ion gi en o hem, ha hey ha e been
able o ask ques ions abou he s udy, ha hey unde s and
ha hei pa icipa ion is olun a y, and ha hey can wi h-
d aw om he s udy whene e hey wan wi hou ha ing o
gi e explana ions and wi hou his ha ing an impac on he
a en ion gi en o hem. On he o he hand, hey will gi e
hei consen o compu e p ocessing o he da a ob ained
o scien ific pu poses, in acco dance wi h legal egula ions.
Discussion
The Vi Tendon-Rehab p ojec aims o ha e a posi i e
impac on he heal h o people diagnosed wi h CT, who
o en su e om di ficul ies in he de elopmen o hei
wo k and domes ic and spo ing ac i i ies. As de ailed in
he In oduc ion, exe cise is beneficial o pa ien s wi h
CT; he e o e, i is expec ed ha he use o he sys em
based on VR exe cises p oposed in his s udy will cause a
dec ease in pain and kinesiophobia, an imp o emen in
mo emen , and consequen ly, a posi i e impac on he
quali y o li e. In addi ion o impac ing he pa icipan s,
he esul s ob ained could be use ul o he possible in eg a-
ion o VR sys ems in o he daily clinical p ac ice o public
and p i a e heal h sys ems.
These esul s build on p e ious esea ch explo ing he
use o VR in he apies o ch onic condi ions, al hough e i-
dence on CT is s ill needed. Cu en me a-analyses sugges
ha he apies in ol ing VR can imp o e he le el o pain
and kinesiophobia, a clinical en i y highly ela ed o
a ious ypes o endinopa hies,
14
in pa ien s wi h a ious
ch onic pa hologies. B ea-Gómez e al.
56
de e mined ha
VR in e en ion educes he le el o pain and kinesiophobia
in pa ien s wi h ch onic low back pain in he sho e m and
a e six mon hs o ollow-up. Simila findings we e
epo ed by Li e al.,
57
concluding ha VR-based aining
educes he le el o pain and kinesiophobia in he immedi-
a e e m. In he con ex o o he ch onic pa hologies, Guo
e al.
58
s a ed ha VR in e en ion o pa ien s wi h neck
pain eflec ed benefi s in pain elie , based on mode a e-
quali y e idence. Fu he mo e, cu en e idence indica es
ha VR is e ec i e in educing kinesiophobia, and is
mo e e ec i e when combined wi h physical exe cise,
59
which suppo s he design o ou s udy. Ne e heless,
al hough he a ailable me a-analyses a e use ul o es ab-
lishing an o e iew o he e ec i eness o VR, he he e o-
genei y among s udies is high and u he esea ch is
needed.
The managemen o pain and kinesiophobia using VR is
sugges ed o be based on he mechanisms o dis ac ion and
embodimen ; ha is, he sensa ion ha he i ual body is an
ex ension o one’s own physical body. Dis ac ion di e s
he pe son’s a en ion away om pain by engaging he
pa ien in a i ual imme si e en i onmen , educing pain
pe cep ion and kinesiophobia.
23
Howe e , Bake e al.
60
s a ed ha he mos common mechanism is dis ac ion,
bu in subjec s wi h ch onic pain, he e is an impo an p es-
ence o he embodimen mechanism as a mechanism o pain
educ ion.
In iew o his o e iew, i should be no ed ha o da e,
o he bes o ou knowledge, no s udy has been ound in he
li e a u e ha includes he use o VR in CT. The e o e, he e
ha e been no p e ious analyses o he neu ophysiological
e ec s o his ype o in e en ion in pa ien s in he
ch onic s ages o his pa hology. Gi en he e iopa hogenic
di e ences, as well as he neu ophysiological and issue di -
e ences be ween he pa hologies p e iously discussed and
CT, i canno be s a ed wi h ce ain y ha his in e en ion
has he same e ec s in pa ien s wi h CT.
Lucena-An on e al. 7
Despi e he limi ed e idence o he e ec i eness o VR
in he ea men o CT, he impo ance o ask-o ien ed
physical exe cise o he eco e y o a ious pa hologies,
including endon inju ies, has been highligh ed in ecen
yea s. Fo example, a clinical guideline highligh ed he
impo ance o an ac i e, ask-o ien ed ehabili a ion
p og am o educe pain and disabili y in adul s wi h
o a o cu diso de s.
61
This ecommenda ion is encou -
aging and sugges s ha he suppo and known benefi s o
VR in e en ion, which a e almos en i ely goal-o ien ed,
may be e ec i e in imp o ing he clinical p ac ice o
pa ien s wi h CT. Howe e , i should be no ed ha ou he-
o e ical basis was es ablished using o he ch onic pa holo-
gies as e e ences because o he lack o e idence
specifically ela ed o CT. This may lead o a po en ial
bias in ou in ended s udy esul s, hus a ec ing he gene -
alizabili y and applicabili y o ou findings. I is impo an
o use cau ion when ex apola ing da a om hese condi-
ions o CT, as hey di e in hei pa hophysiology and
ea men equi emen s. Al hough VR-based in e en ions
ha e demons a ed e ficacy in he ea men o o he
ch onic pain condi ions, he unique cha ac e is ics o CT,
specifically he need o app op ia e mechanical loading
o p omo e endon healing,
62
may esul in di e en he a-
peu ic ou comes.
I should be no ed ha he ch onici y o endinopa hy no
only a ec s he physiology o endon issue
63,64
bu may
also influence he psychological and social aspec s o
pa ien s su e ing om i .
65
This ac is undamen al when
conside ing ac i e in e en ions, whe e pa ien engagemen
in ea men and he le el o pa ien sa is ac ion a e a i-
ables o u mos impo ance. In his con ex , ou s udy
aimed o imp o e pa ien engagemen and sa is ac ion in
pa ien s unde going CT using a ool ha , al hough inc eas-
ingly used, is s ill no el o he gene al popula ion, such as
VR. In addi ion o add essing he clinical needs o pa ien s,
his s udy may open new lines o esea ch explo ing he
implemen a ion o VR in di e en a eas o ele ehabili a ion
and pe sonalized ea men , whe e he ole o he A ificial
In elligence (AI) will be c ucial. AI could p e en inju ies
by examining biomechanical and physiological in o ma ion
o an icipa e po en ial ha m and ack eco e y p og ess. In
his sense, p edic i e analy ics will use his o ical and
cu en da a o assess human pe o mance and suppo s a-
egic clinical decision-making.
66
S eng hs and limi a ions o he s udy
This s udy has se e al s eng hs ha highligh he po en ial
impac o hese findings on he ea men o pa ien s wi h
CT. One o he main s eng hs o his s udy is i s echno-
logical inno a ion, which employs VR o c ea e sa e and
con olled en i onmen s o pa ien s. This app oach no
only acili a es physical ehabili a ion, bu also add esses
psychological aspec s, such as kinesiophobia, by o e ing
a di e en expe ience om he con en ional ea men
model. This expe ience is imme si e and mo i a ing. VR
in e en ions ha e he po en ial o adap exe cises o he
indi idual needs o pa ien s, he eby imp o ing he ea -
men e ficacy. Fu he mo e, he e sa ili y o VR, coupled
wi h he po abili y o he de ice, sugges s ha i could be
a aluable ool o o he fields o ea men , such as ele eh-
abili a ion. Mo eo e , a comp ehensi e assessmen o he
a ious clinical pa ame e s included in he s udy, such as
pain, physical unc ion, ROM, s eng h, and quali y o
li e, p o ides a comple e unde s anding o he impac o
he in e en ion. Fu he mo e, he play ul and mo i a ing
na u e o VR is expec ed o p omo e high pa ien sa is ac-
ion wi h ea men , which is c ucial o i s long- e m
success.
Ne e heless, i is impo an o acknowledge ha his
s udy has se e al limi a ions ha should be conside ed
when in e p e ing he esul s. One po en ial limi a ion o
he s udy is he possibili y o use discom o o diso ien a-
ion associa ed wi h VR, pa icula ly in olde adul s o hose
un amilia wi h digi al echnology. To add ess his, we ha e
designed a aining session wi h g adual in oduc ion o
amilia ize pa icipan s wi h he VR sys em and will
p o ide ongoing echnical suppo h oughou he s udy.
The flexibili y o he VR so wa e will also allow o cus-
omiza ion o exe cises, ensu ing ha he expe ience is ai-
lo ed o he capabili ies o each pa icipan . A possible
limi a ion o his s udy is ela ed o he di e ence in o al
p og am du a ion be ween he wo s udy g oups. In addi ion
o he p og am pe o med by he con ol g oup, he
VR-based in e en ion p og am will be conduc ed o 15
min. This issue may gi e ise o a possible bias since he
in e en ion g oup ob ained supe io esul s compa ed o
he con ol g oup, which could be due o he inc eased
he apy ime ecei ed. Howe e , an a emp has been
made o mi iga e his limi a ion, including he o al
p og am du a ion as a co a ia e and pe o ming a sensi i -
i y analysis. Ano he po en ial limi a ion is he loss o pa -
icipan s du ing he ollow-up pe iod, which could a ec he
alidi y and gene alizabili y o he esul s. In addi ion, he
ec ui men o pa icipan s in p i a e clinics may esul in
selec ion bias, he eby limi ing he applicabili y o he find-
ings o o he clinical se ings. Despi e calcula ing he
op imal sample size o de ec significan di e ences, a
small sample size could limi he abili y o de ec mino
e ec s and educe he s a is ical powe o he s udy. The
na u e o he in e en ion makes i impossible o pe o m
comple e blinding, which in oduces he po en ial o
expec a ion bias in sel - epo ed pa ien ou comes in single-
blind s udies. Pa icipan d opou du ing he ollow-up
pe iod is a po en ial limi a ion o he s udy and could
a ec he alidi y and gene alizabili y o he esul s. To
add ess his, we ha e ou lined se e al e en ion s a egies,
including pe sonalized ollow-up, flexible scheduling, and
incen i es o main ain pa icipan engagemen h oughou
8DIGITAL HEALTH
he ial. Fu he mo e, we will implemen in en ion- o- ea
analysis and mul iple impu a ion echniques o handle
missing da a and educe po en ial biases. Sensi i i y ana-
lyses will also be conduc ed o examine he obus ness o
he findings, ensu ing ha he impac o d opou is mini-
mized. Finally, al hough alidi y s udies exis o he
scales used, some ha e no been alida ed in ou s udy
popula ion. Fu he mo e, al hough he CRES-4 scale has
been used in p e ious s udies in ol ing Spanish-speaking
popula ions,
67–69
he e is a lack o alida ion specifically
in pa ien s wi h CT. The absence o alida ion could
esul in measu emen bias, po en ially unde - o o e es i-
ma ing pa ien sa is ac ion wi h he in e en ion, a ec ing
he gene alizabili y o he esul s ob ained. In his sense,
we will in e p e he esul s wi h cau ion o mi iga e his
issue. The e o e, i is essen ial o add ess hese limi a ions
in o de o ensu e he alidi y and gene alizabili y o he
esul s.
Conclusion
The Vi Tendon-Rehab s udy p o ocol is designed o
esea ch he e ec i eness o a VR-based exe cise
p og am in people wi h CT. Based on he cu en scien ific
li e a u e, his p og am may esul in imp o emen s in pain
and kinesiophobia h ough hypoalgesic mechanisms, pain
dis ac ion, ask epe i ion, ocused a en ion on he ask,
and g adual exposu e o mo emen . Consequen ly,
imp o emen s in pain and kinesiophobia could ha e a posi-
i e impac on he ou comes o his s udy. I such esul s a e
ob ained, inclusion o his in e en ion p og am in he clin-
ical p ac ice o heal hca e cen e s should be conside ed.
Acknowledgemen s:We would like o hank he Uni e si y o
Cadiz o unding his s udy.
Con ibu o ship: DLA and JAM-M we e he p incipal
in es iga o s o his s udy. CL-M, MJS-C, JCC-B, JGD-R we e
in ol ed in he p o ocol de elopmen and e hical app o al. The
fi s d a o he manusc ip was w i en by DLA, JAM-M, and
JGD-R. All au ho s e iewed and edi ed he manusc ip and
app o ed i s final e sion.
Decla a ion o conflic ing in e es s: The au ho s decla ed no
po en ial conflic s o in e es wi h espec o he esea ch,
au ho ship, and/o publica ion o his a icle.
E hical app o al: This clinical ial has been app o ed by he
E hical Commi ee o he P o ince o Cádiz (Cádiz, Spain)
(Regis e numbe : 31.23).
Funding: The au ho s disclosed eceip o he ollowing financial
suppo o he esea ch, au ho ship, and/o publica ion o his
a icle: This wo k was suppo ed by he Uni e si y o Cadiz
wi hin he amewo k o a p ojec g an ed by “Plan P opio
UCA”[g an numbe PR2022-049].
Gua an o : DLA.
ORCID iDs: Da id Lucena-An on h ps://o cid.o g/0000-0003-
2441-5342
Jose A Mo al-Munoz h ps://o cid.o g/0000-0002-6465-982X
Supplemen al ma e ial: Supplemen al ma e ial o his a icle is
a ailable online.
Re e ences
1. Cook JL and Pu dam CR. Is endon pa hology a con inuum?
A pa hology model o explain he clinical p esen a ion o
load-induced endinopa hy. B J Spo s Med 2009; 43:
409–416.
2. Milla NL, Silbe nagel KG, Tho bo g K, e al. Tendinopa hy.
Na Re Dis P ime s 2021; 7: 1.
3. Almekinde s LC and Almekinde s SV. Ou come in he ea -
men o ch onic o e use spo s inju ies: a e ospec i e s udy.
J O hop Spo s Phys The 1994; 19: 157–161.
4. Junio LCH, Ca alho ACA, Cos a LOP, e al. The p e alence
o musculoskele al inju ies in unne s: a sys ema ic e iew.
B J Spo s Med 2011; 45: 351–352.
5. Kaux J-F, Fo homme B, Le GC, e al. Cu en opinions on
endinopa hy. J Spo s Sci Med 2011; 10: 238–253.
6. G uchow HW and Pelle ie D. An epidemiologic s udy o
ennis elbow. Am J Spo s Med 1979; 7: 234–238.
7. Weie AT, Pea ce AJ and Kidgell DJ. S eng h aining
educes in aco ical inhibi ion. Ac a Physiol 2012; 206:
109–119.
8. Rio E, Kidgell D, Moseley GL, e al. Ele a ed co icospinal
exci abili y in pa ella endinopa hy compa ed wi h o he
an e io knee pain o no pain. Scand J Med Sci Spo s 2016;
26: 1072–1079.
9. Rio E, Kidgell D, Moseley GL, e al. Tendon neu oplas ic
aining: changing he way we hink abou endon ehabili a-
ion: a na a i e e iew. B J Spo s Med 2016; 50: 209–215.
10. Edga N, Cli o d C, O’Neill S, e al. Biopsychosocial
app oach o endinopa hy. BMJ Open Spo Exe c Med
2022; 8: e001326.
11. Plinsinga ML, B ink MS, Vicenzino B, e al. E idence o
ne ous sys em sensi iza ion in commonly p esen ing and pe -
sis en pain ul endinopa hies: a sys ema ic e iew. J O hop
Spo s Phys The 2015; 45: 864–875.
12. Bascou -Sando al C, Salgado-Salgado S, Gómez-Milán E,
e al. Pain and dis ac ion acco ding o senso y modali ies:
cu en findings and u u e di ec ions. Pain P ac 2019; 19:
686–702.
13. La Touche R, Pa is Alemany A and Gue a A mas J. Sesgos
a encionales y es a egias de dis acción: implicaciones pa a la
comp ensión y a amien o del dolo . J Mo e The Sci 2024;
5: 529–541.
14. Mallows A, Debenham J, Walke T, e al. Associa ion o psy-
chological a iables and ou come in endinopa hy: a sys em-
a ic e iew. B J Spo s Med 2017; 51: 743–748.
Lucena-An on e al. 9
