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Effectiveness of the custom-mold room temperature vulcanizing silicone toe separator on hallux valgus: A prospective, randomized single-blinded controlled trial

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Background: Silicone toe separator is considered as a conservative treatment for hallux valgus. The prefabricated toe separator does not fit all. However, effectiveness in prescription of the custom-mold toe separator is still unknown. Objectives: To investigate the effect of using a custom-mold room temperature vulcanizing silicone toe separator to decrease hallux valgus angle and hallux pain. The compliances, complications, and satisfactions of toe separator were also explored. Study design: A prospective, randomized single-blinded controlled trial. Methods: A total of 90 patients with a moderate degree of hallux valgus were enrolled in a study at the Foot Clinic, Siriraj Hospital, Thailand. Patients were randomized into two groups; the study group was prescribed a custom-mold room temperature vulcanizing silicone toe separator for 6 h per night for 12 months. Patients in both groups received proper foot care and shoes and were permitted to continue drug treatment. Results: In total, 40 patients in the study group and 39 patients in the control group completed the study. The hallux valgus angle was obtained through radiographic measurement. At month 12, both groups had significant differences in mean hallux valgus angle with a decrease of 3.3° ± 2.4° for the study group and increase of 1.9° ± 1.9° for the control group. There were statistically significant differences of hallux valgus angle between the two groups ( p < 0.05) at the end of the study. Hallux pain was decreased in the study group. Conclusion: A custom-mold room temperature vulcanizing silicone toe separator can decrease hallux valgus angle and pain with no serious complications. Clinical relevance The custom-mold room temperature vulcanizing silicone toe separator for treatment of hallux valgus reduces deformity and hallux pain.
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https://doi.org/10.1177/0309364617698518
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DOI: 10.1177/0309364617698518
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INTERNATIONAL
SOCIETY FOR PROSTHETICS
AND ORTHOTICS
Background
Hallux valgus is a common forefoot deformity that refers
to an abnormal angulation of the great toe deviated later-
ally and the first metatarsal deviated medially.1 Pulling
forces from the long flexor and extensor tendons cause the
metatarsal head to move medially2 and the great toe to
crowd toward the second or third toes. Unquestionably,
the cause of HV is multifactorial. The combinations of
intrinsic and extrinsic factors have been considered,3 such
as the structure of pes planus,4 functional tightness of the
Achilles tendon,5 and degenerative joint disease at the
first metatarsophalangeal joint.6 A family history of the
condition has also been found as a major causal factor.7,8
Effectiveness of the custom-mold room
temperature vulcanizing silicone toe
separator on hallux valgus: A prospective,
randomized single-blinded controlled trial
Navaporn Chadchavalpanichaya, Voraluck Prakotmongkol,
Nattapong Polhan, Pitchaya Rayothee and Sirirat Seng-Iad
Abstract
Background: Silicone toe separator is considered as a conservative treatment for hallux valgus. The prefabricated toe
separator does not fit all. However, effectiveness in prescription of the custom-mold toe separator is still unknown.
Objectives: To investigate the effect of using a custom-mold room temperature vulcanizing silicone toe separator to decrease
hallux valgus angle and hallux pain. The compliances, complications, and satisfactions of toe separator were also explored.
Study design: A prospective, randomized single-blinded controlled trial.
Methods: A total of 90 patients with a moderate degree of hallux valgus were enrolled in a study at the Foot Clinic, Siriraj
Hospital, Thailand. Patients were randomized into two groups; the study group was prescribed a custom-mold room
temperature vulcanizing silicone toe separator for 6 h per night for 12 months. Patients in both groups received proper
foot care and shoes and were permitted to continue drug treatment.
Results: In total, 40 patients in the study group and 39 patients in the control group completed the study. The hallux valgus
angle was obtained through radiographic measurement. At month 12, both groups had significant differences in mean hallux
valgus angle with a decrease of 3.3° ± 2.4° for the study group and increase of 1.9° ± 1.9° for the control group. There were
statistically significant differences of hallux valgus angle between the two groups (p < 0.05) at the end of the study. Hallux
pain was decreased in the study group.
Conclusion: A custom-mold room temperature vulcanizing silicone toe separator can decrease hallux valgus angle and pain
with no serious complications.
Clinical relevance
The custom-mold room temperature vulcanizing silicone toe separator for treatment of hallux valgus reduces deformity
and hallux pain.
Keywords
Custom mold, developing countries, hallux valgus, lower limb orthotics, silicone elastomer, toe separator
Date received: 27 April 2016; accepted: 7 February 2017
Sirindhorn School of Prosthetics and Orthotics, Faculty of Medicine
Siriraj Hospital, Mahidol University, Bangkok, Thailand
Corresponding author:
Voraluck Prakotmongkol, Sirindhorn School of Prosthetics and
Orthotics, Faculty of Medicine Siriraj Hospital, Mahidol University,
Bangkok 10700, Thailand.
Email: voraluck.pra@mahidol.edu
698518POI0010.1177/0309364617698518Prosthetics and Orthotics InternationalChadchavalpanichaya et al.
research-article2017
Original Research Report
2 Prosthetics and Orthotics International
Moreover, HV has a tendency to present itself in individu-
als who wear ill-fitting shoes with pointed toe box and
high heels,3,9,10 which have been shown to increase the
risk of developing the condition by upward of 15 times
compared to use of regular footwear.11
Major complaints from patients who visit physician
offices are pain in the form of a bunion or calluses and
corns. Shearing and distension occurs at the medial cap-
sule or the proper plantar digital nerves of the medial
plantar nerve. Without treatment, the deformity can con-
tinue to develop. The degree of severity of HV is classi-
fied by various ranges of the hallux valgus angle (HVA)
and deviation pattern.12
Treatments for HV are either conservative or operative
in nature.13 The common conservative interventions are
proper fitting footwear with a wide deep toe box,14 stretch-
ing exercises,15,16 therapeutic cold treatment,17 nonsteroi-
dal anti-inflammatory drugs (NSAIDs),18 and muscle
relaxants.19 A variety of orthoses have been prescribed as
treatment: insoles,20 pads, night splints, and toe separators
(TS).21 Previous studies have suggested that TS is one of
the most common treatments to alleviate pain, improve toe
alignment, increase biomechanical function, and improve
walking patterns.22,23
The TS is commonly made of silicone. Prefabricated
silicone TS are commonly prescribed to slow the progres-
sion of HV. However, this type of device does not provide
the ideal intimate fit.24 A loose fit and slippage22 can cause
shear forces and lead to pain over affected toes. As a result,
potential acceptance and compliance by the patient can be
decreased. A custom-made TS is another option that can
reduce these problems by providing a more intimate and
improved fit.
Although there are benefits to using custom options,
some patients cannot afford high-cost TS which typically
cost about US$250. Using a low-cost material that is not
traditionally utilized for a TS is potentially a novel approach
to HV treatment. It is because of the aforementioned issues
that the authors decided to investigate the effectiveness of a
custom silicone orthosis as a formidable low-cost option
for treating HV.
We choose to use a room temperature vulcanizing
(RTV) silicone (RTV585) which costs US$17 per kilo-
gram. Previous research utilized liquid silicone to fabricate
medial arch supports and foot orthoses for treatment of
foot problems.25,26 However, there are no studies reporting
the effectiveness of a TS made from RTV silicone to
decrease the HV deformity. Therefore, a randomized con-
trol trial study consisting of a treatment group and control
group was conducted.
The primary objective of this study was to determine the
effectiveness of the custom-mold RTV silicone toe separa-
tor to decrease HVA in individuals diagnosed with HV.
The secondary objective was to determine the effective-
ness of the custom-mold RTV silicone toe separator to
decrease hallux pain (pain of the big toe) as well as inves-
tigate possible complications, patient compliance, and
satisfaction.
Methods
Subjects
The study protocol was reviewed and approved by the
Institutional Review Board at Siriraj Hospital, Bangkok,
Thailand (Si361/2013) and was supported by the Siriraj
Research Development Fund (managed by Routine to
Research: R2R). From January to December 2013, 90
patients who had HV were recruited to participate in the
study. A physiatrist who specialized in foot problems per-
formed a complete foot examination and provided the
clinical diagnosis of HV. The inclusion criteria for partici-
pation in the study were males and/or females from 18 to
80 years with a moderate degree of HV (HVA: 20°–40°).12
Previous literature identified a mean HVA of 30° as a
“moderate to severe degree of deformity.”27 The patients
were excluded from the study if the following were pre-
sent: foot numbness or foot ulcer, having acute inflamma-
tion of first metatarsophalangeal joint, having hallux
rigidus or hallux limitus, continuously using any types of
TS or HV strap in the past year, or having silicone aller-
gies. If the patients had a moderate degree of HV bilater-
ally, the more severe of the two was chosen for the study,
as determined by radiographic measurement.
Sample size calculation
Our sample size calculation was based on the ability to
detect a clinically important difference in HVA, where the
clinically significant change of HVA was 5°. Based on a
power of 0.80 to detect a significant difference (5% type I
error and 20% type II error, p = 0.05, two-sided), 37 patients
were required for both the study group and the control
group. The recruited sample size was 90 subjects in total
(45 subjects per group with an estimated 20% drop-out).
Study protocol
Once the study eligibility was confirmed, an information
sheet and verbal explanation were provided to the patients,
and a signed informed consent form was obtained prior to
study participation. The patients were then randomly allo-
cated to either a study group or a control group by a
research coordinator. The patients had an equal probability
of assignment to each of the groups.
Patients in both groups were given standard treatment
including proper foot care which included removing any
calluses at the plantar or medial side of the foot and provi-
sion of low-heel shoes with a wide-and-deep toe box. Only
the patients who were randomized to the study group were
Chadchavalpanichaya et al. 3
referred to the orthotist who prepared the custom-mold
RTV silicone toe separator.
Apparatus
Each patient in the study group was cast in a corrected
position for a mold. A silicone TS was then produced from
the mold (Figure 1).
Patients were recommended to wear the device at least
6 h/day during the night. If any signs of irritation or dis-
comfort occurred, the patients were instructed to contact
the physiatrist immediately. Patients were provided with
logbooks, questionnaires, and follow-ups every 3 months.
Data collection
At baseline, patient demographics were collected, as well
as average hours worn in walking shoes, foot issues on
side of deformity, duration of HV, and family history
(Table 1). The impact of deformity on the patient’s ability
to walk and shoe-fitting problems were recorded using a
numeric rating scale (NRS). The questions were scored
from 0 (no problem) to 10 (worst problem).
The primary outcome measure in this study was the
HVA, which was obtained from both the study group and
the control group through measurement of a weight-bear-
ing anteroposterior radiograph. Each radiographic image
was evaluated at months 6 and 12 by a physiatrist and a
radiologist who were blinded to the groups of participants.
The HVA of months 6 and 12 were averaged by taking
recorded values obtained by both raters.
The secondary outcome measures were hallux pain,
compliance, complication, and satisfaction. At baseline
and every 3 months, hallux pain experienced within the
last 24 h was obtained from a questionnaire which used an
NRS scored from 0 (no pain) to 10 (worst pain).
Compliance was measured by recording the hours of
device usage per day which was then averaged each
week and reported in the logbook. Any complications
caused by the device such as abrasions or rashes were
also recorded. Furthermore, at the end of the study, the
treatment satisfaction in six sub-domains—fitting, com-
fort, perspiration, cosmetic appearance, maintenance,
and overall satisfaction—were recorded. An NRS scored
as 0 (dissatisfaction) to 10 (most satisfaction) from both
groups was used. Intentions for future use as well as sug-
gestions for improving the quality of the device were
recorded.
Statistical analysis
All statistical analyses were performed using PASW
Statistics (SPSS) 18.0 (SPSS, Inc., Chicago, IL, USA) and
a p value of less than 0.05 was considered a statistically
significant difference. The outcome measures were
reported by both per protocol (PP) and intention-to-treat
(ITT) analysis. In PP treatment, tests were performed to
perform statistical analysis solely on participants who
completed the full treatment. The ITT was performed
because it is a reliable test which takes into account the
“last value carried forward” regardless of whether or not
the subject drops out of the study.
The median (range) was calculated for duration of HV
problem (years), impact of the HV deformity, hallux pain,
and satisfaction (NRS from 0 to 10). Patient compliance
using the RTV silicone toe separator (h/day) was calcu-
lated by mean and standard deviation (SD). Any complica-
tions and the participant’s future intention of using the
device were calculated as a number and percentage. For
demographic data, an unpaired t-test and Mann–Whitney
test were used to analyze the differences of quantitative
data with normal distribution and non-normal distribution,
respectively. Additionally, Fisher’s exact test and chi-
square test were performed to analyze the differences of
categorical data.
To explore the primary outcome of HVAs, as measured
in degrees, a repeated-measures analysis of variance
(ANOVA) with the use of a Bonferroni correction for mul-
tiple comparisons was used to analyze the differences
between the study group and the control group at baseline,
month 6, and month 12 as well as the relationship of the
data in the same group between different timelines.
To explore the secondary outcomes of hallux pain,
compliance, complication, and satisfaction, the Friedman
test was performed, and Bonferroni correction for multiple
comparisons was used to analyze the difference of the data
between pre- and post-intervention in the same group. The
Mann–Whitney U test was used to analyze the differences
Figure 1. The custom-mold room temperature vulcanizing
silicone toe separator.
4 Prosthetics and Orthotics International
between the study group and the control group at the base-
line and months 3, 6, 9, and 12.
Results
A total of 90 patients participated in the study. Half of
them were randomly allocated into the study group and
another half into the control group. In total, 43 patients
from the study group (95.56%) and 42 patients in the con-
trol group (93.33%) returned for follow-up at months 3
and 6. In addition, 40 patients from the study group
(88.89%) and 39 patients in the control group (86.67%)
returned for follow-up at month 9 and continued participa-
tion until the end (Figure 2).
Table 1 summarizes the characteristics and foot prob-
lems of participants. The analysis of the baseline measure-
ments of two groups reveals the similarities with regard to
age, gender, body mass index (BMI), duration of shoe wear,
duration of HV history, family history, and walking and
shoe-fitting problems from HV. The analysis indicated that
there were no significant differences between the two
groups for the aforementioned measurements (p > 0.05). At
baseline, there was a significant difference in the number of
hours spent standing and/or walking at work between the
two groups, 5 and 4 h, respectively. The differences in loca-
tion of HV deformity with reference to foot side are noted.
Primary outcome
The HVA was measured at baseline, month 6, and month 12
and reported in both PP and ITT analysis as presented in
Table 2. At baseline, there was no significant difference in
HVA between groups, although the study group had more
severe HVA (of 32.0° ± 4.8° compared to 30.6° ± 5.2°).
After 12 months of using the TS, the HVA of the study
group decreased 3.3° ± 2.4° from 32.0° ± 4.8° to 28.8° ± 5.8°,
whereas the HVA of the control group increased 1.9° ± 1.9°
from 30.6° ± 5.2° to 32.5° ± 5.4° (Figure 3).
Table 1. Baseline demographic and clinical characteristics.
Characteristics Study group (n = 45) Control group (n = 45) p value
Age (mean ± SD, years) 60.3 ± 9.4 60.8 ± 10.8 0.804b
Gender (n (%))
Female 44 (97.8) 41 (91.1) 0.361c
BMI (mean ± SD, (kg/m2)) 23.9 ± 3.1 25.3 ± 3.3 0.056b
Standing or walking hours during work
(median (range), h/day)
5 (1, 12) 4 (0.5, 10) 0.04a,d
Duration of shoes wear (h/day), (n (%)) 0.266e
No 0 0
<1 0 0
1–4 18 (40.0) 15 (33.3)
5–8 21 (46.7) 17 (37.8)
9–12 4 (8.9) 11 (24.5)
>12 2 (4.4) 2 (4.4)
Hallux valgus problems
Side (n (%))
Right 2 (4.4) 6 (13.3) 0.013a,e
Left 3 (6.7) 11 (24.5)
Bilateral 40 (88.9) 28 (62.2)
Duration (year), median (range) 10 (1, 60) 10 (1, 50) 0.644b
Family history (n (%))
Yes 27 (60) 25 (55.6) 0.670e
Problem from hallux valgusa
Median (range)
Walking problems 1 (0, 10) 0 (0, 9) 0.496d
Shoes fitting problems 5 (0, 10) 5 (0, 10) 0.945d
Working problems 0 (0, 9) 0 (0, 8) 0.040a,d
Daily activity problems 0 (0, 10) 0 (0, 8) 0.037a,d
SD: standard deviation; BMI: body mass index.
aMeasured by numeric rating scale (0: no problem, 10: worst problem).
bUnpaired t-test.
cFisher’s exact test.
dMann–Whitney U test.
eChi-square test.
Chadchavalpanichaya et al. 5
For the baseline of ITT, the study group showed a more
severe HVA of 32.5° ± 4.8° compared to 30.3° ± 5.2°,
which made a significant difference in the HVA between
groups (p < 0.05). After 12 months of using the TS, the
Figure 2. Flow diagram explaining patient participation. CA: cancer.
Table 2. Hallux valgus angle (mean ± SD), hallux pain median (min, max), and difference of hallux valgus angle pre- and post-
intervention using the custom-mold RTV silicone toe separator.
Per protocol ITT
Study Control p valuecStudy
(n = 45)
Control
(n = 45)
p valuec
Hallux valgus angle
(mean ± SD, (°))
Baseline 32.0 ± 4.8 (n = 45) 30.6 ± 5.2 (n = 45) 0.199 32.5 ± 4.8 30.3 ± 5.2 0.038
Month 6 29.8 ± 5.2 (n = 43) 32.1 ± 5.2 (n = 42) 0.057 30.4 ± 5.4 31.7 ± 5.3 0.254
Month 12 28.8 ± 5.8 (n = 40) 32.5 ± 5.4 (n = 39) 0.004 29.5 ± 5.9 32.1 ± 5.4 0.032
p valued<0.001e<0.001e<0.001e<0.001e
Difference of hallux valgus
angle pre- and post-
interventiona (mean ± SD, (°))
0–6 months 2.2 ± 1.8 (n = 43) −1.5 ± 1.9 (n = 42) <0.001f2.1 ± 1.8 −1.4 ± 1.8 <0.001f
0–12 months 3.3 ± 2.4 (n = 40) −1.9 ± 1.9 (n = 39) <0.001f3.0 ± 2.4 −1.8 ± 1.8 <0.001f
Hallux painb median (min,
max)
Baseline 3 (0, 10) (n = 45) 0.5 (0, 8) (n = 45) 0.136g3 (0, 10) 1 (0, 8) 0.090g
Month 3 1 (0, 5) (n = 43) 0 (0, 8) (n = 42) 0.552g2 (0, 8) 0 (0, 8) 0.415g
Month 6 0.5 (0, 5) (n = 43) 0 (0, 9) (n = 42) 0.894g1 (0, 8) 0 (0, 9) 0.836g
Month 9 0 (0, 5) (n = 40) 0 (0, 9) (n = 39) 0.088g0 (0, 8) 0 (0, 9) 0.286g
Month 12 0 (0, 5) (n = 40) 0 (0, 9) (n = 39) 0.111g0 (0, 8) 0 (0, 9) 0.365g
p valued<0.001h0.866h<0.001h0.866
SD: standard deviation; RTV: room temperature vulcanizing; ITT: intention to treat. In this table bold values indicate a statistically significant
difference with a p-value less than 0.05.
a Calculated by pre-intervention angle minus post-intervention angle (minus value means post-intervention score is more than pre-intervention score).
b Hallux pain measured by numeric rating scale (0: no pain, 10: the most pain) as a secondary variable.
c
Comparison between the study and control group.
d Comparison between the pre- and post-intervention in the same group.
e Analyzed by repeated-measures analysis of variance (ANOVA) with the use of Bonferroni correction for multiple comparisons.
f
Unpaired t-test.
g
Mann–Whitney U test.
h Analyzed by Friedman test with the use of Bonferroni correction for multiple comparisons.
6 Prosthetics and Orthotics International
HVA of the study group improved 3.0° ± 2.4° from
32.5° ± 4.8° to 29.5° ± 5.9°, while the HVA of the control
group increased 1.8° ± 1.8° from 30.3° ± 5.2° to 32.1° ± 5.4°
(Figure 4). The analysis showed significant differences of
HVA between pre- and post-intervention, at months 6 and
12, respectively, in both groups (p < 0.05) (Figures 3 and
4). In Table 2, there were significant differences of HVA at
month 12 between both groups as analyzed by a repeated-
measures ANOVA with use of the Bonferroni correction
for multiple comparisons. Further analysis by an unpaired
t-test revealed that there were significant differences of the
mean of pre- and post-intervention HVA (months 0–6 and
0–12) between both groups (p < 0.05).
Secondary outcomes
Hallux pain is reported in both analysis methods (Table 2).
There was no significant difference of hallux pain between
two groups at baseline (p > 0.05). Analysis from both
methods showed similar outcomes. However, the results
show a decrease of hallux pain in the study group. The
analysis of hallux pain showed significant differences in
pain between pre-intervention and at months 6, 9, and 12
but only for the study group (p < 0.05). The analysis by
Mann–Whitney U test revealed that there were no signifi-
cant differences of hallux pain between two groups at the
end of the study.
A summary of compliance with using the RTV silicone
toe separator in the study group showed that 42 patients
(93.33%) returned their logbooks at months 3 and 6, and
only 39 patients (86.67%) returned their logbooks at
months 9 and 12. Data from logbooks of the study group
showed the highest mean ± SD of compliance in the first
3 months at 7.0 ± 2.7 h/day and 44.7 ± 18.5 h/week and the
lowest mean ± SD of compliance in the last 3 months at
6.9 ± 3.6 h/day and 42.6 ± 25.6 h/week.
Complications from using the device were seen in six
patients (15% of the study group), but the number of
affected patients was not significant according to our sam-
ple size. No subjects had serious complications, yet mild
pain at the hallux and second toe were noted.
Satisfaction with the RTV silicone toe separator are
presented in Table 3. The satisfaction scores were high in
every category. The median (range) satisfaction score of
the overall treatment of the study group was 9 (3, 10) and
only 5 (0, 10) in the control group. There was a significant
difference in the overall treatment satisfaction score
between two groups (p < 0.001).
As for the intent of the patient to use this device in the
future, 31 patients (81.6% of study group) confirmed that
they would continue using their devices. Six patients
(15.8% of study group) reported that they might continue
using their devices and one patient stated she would stop
using the device and made no reference as to why.
Discussion
Our study examined the role a low-cost silicone custom-
mold toe separator for HV had on reducing HVA, pain, and
compliance as well as the satisfaction of the device. The
results demonstrated a significant decrease in HVA in the
study group and an increase in HVA in the control group
which was provided with a proper shoe only. Previous
investigations with interventions focused on management
of HV have suggested that a reduction in HVA might be
Figure 3. Hallux valgus angles (HVA) at baseline of the study,
month 6, and month 12 as reported in per protocol analysis.
Figure 4. Hallux valgus angles (HVA) at baseline of the study,
month 6, and month 12 as reported in the intention-to-treat
(ITT) analysis.
Table 3. Satisfaction with the custom-mold RTV silicone toe
separator using the NRS (n = 40).
Median (min, max)
Fitting 8 (2, 10)
Comfort 9 (3, 10)
Perspiration 8 (3, 10)
Cosmetic appearance 8 (3, 10)
Maintenance 9 (5, 10)
Overall satisfaction 9 (3, 10)
RTV: room temperature vulcanizing; NRS: numeric rating scale (0: no
satisfaction, 10: most satisfaction).
Chadchavalpanichaya et al. 7
due to a prolonged corrective positioning of the hallux,
which facilitates stretching of the soft tissues and strength-
ening of the abductor hallucis muscle.14
The results presented from both ITT and PP methods
provided significant differences of mean HVA for com-
parisons between the study and control group. The PP
analysis method excluded participants dropping out while
ITT included all participant data. The significant differ-
ence seen in the ITT is more indicative of real clinical situ-
ations and helps to identify the effect of the intervention.
Participants felt the custom-mold RTV silicone TS was
comfortable to wear. Personalizing the TS takes into con-
sideration the unique and individual anatomy of the
patient. Previous studies comparing custom and off-the-
shelf interventions for HV observed an increase in comfort
when using custom-fabricated devices.24
The complications of the TS were reported during the
first 3-month period of use. A limited number of patients
needed minor adjustment due to discomfort of the second
toe space. Mild pain at the hallux as a result of unaccus-
tomed adjustment was observed in these cases but later
subsided. These patients felt satisfied to continue using the
TS with no further reports of disuse or complications.
Participant compliance was highest in the first 3 months
but lower for the remaining duration of treatment. A previ-
ous study comparing the compliance of nighttime HV
strap elicited use of 5–6 h per night while the compliance
of RTV silicone toe separator was higher at about 7 h. In
addition, the custom-mold RTV silicone toe separator elic-
ited the greater HVA reduction at 3.3° ± 2.4°, while a study
using a commercial nighttime HV strap presented the
mean difference of HVA at −0.8° ± 3.7°.27
The cost of the custom-made RTV silicone toe separa-
tor is approximately US$30 each, whereas the commer-
cially custom-made TS made from medical grade silicone
is approximately US$250 each. Therefore, the custom-
mold RTV silicone toe separator not only enhances clinical
effectiveness in the treatment of HV, but it is also a cost-
effective option.
Previous literature has revealed an intrinsic role pes
planus plays in exacerbating HV,5 and intervention such
as foot orthoses might influence HV.22,23 Our rationale for
omitting measurements of baseline pes planus was due to
the fact that our device was intended for use in non-
weight bearing during sleeping hours. Taking into
account the role of pes planus in interventions designed
to address HV is an important point that can be consid-
ered in future research.
Conclusion
The prescription of custom-mold RTV silicone toe separa-
tor during the night for 1 year as treatment for patients who
have a moderate degree of HV decreased the HVA and hal-
lux pain and provided good satisfaction with the device
without serious complications. The benefits of using this
conservative treatment method could appeal to practition-
ers desiring to provide a low-cost and effective device for
individuals with HV.
Author contribution
All authors contributed equally in the preparation of this
manuscript.
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this
article.
Funding
The author(s) disclosed receipt of the following financial support
for the research, authorship, and/or publication of this article:
This work was supported by Siriraj Research Development Fund
(managed by Routine to Research: R2R).
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... 11 21 22 Nevertheless, evidence on the effects of orthoses and insoles for individuals with HV is inconclusive. [22][23][24][25][26] A systematic review 24 concluded that dynamic and static orthoses with a toe separator effectively reduced the HV angle and pain. Also, according to Chadchavalpanichaya et al, the use of a customised silicone toe separator for 12 months promoted a moderate decrease in pain and HV angle (reduction of 3.3° measured using anteroposterior photography). ...
... Also, according to Chadchavalpanichaya et al, the use of a customised silicone toe separator for 12 months promoted a moderate decrease in pain and HV angle (reduction of 3.3° measured using anteroposterior photography). 25 Another study showed decreased HV angle and improved pain and walking ability after using a full-contact insole with a toe separator for 3 months. 26 Given the lack of consensus on the ideal insole or its length of use for individuals with HV, we suggest a customised insole with retrocapital bar and an infracapital bar of the first metatarsal to increase the contact surface of the forefoot and contribute to reducing pain and pressure in the metatarsal region. ...
... 29 37 47 Despite the lack of robust and sufficient scientific evidence recommending insoles for individuals with HV, several models are presented in literature, such as Open access semi-rigid full-contact insoles moulded with the joint in neutral position, manufactured in a ¾ polypropylene base with forefoot extension in EVA; 33 contact insole manufactured in thermoplastic elastomer in three lengths (full base, infracapital base and retrocapital base); 34 and fullcontact insole moulded in neutral position, manufactured in plastazote poron and adapted with a silicone toe separator. 26 Previous studies used several treatment lengths to assess the effects of customised insoles in the targeted population, including 1 month, 19 22 3 months, 25 34 6 months 23 and 12 months. 47 We outlined a time of 3 months because studies conducted within this period demonstrated adequate methodological designs and less risk of bias than other studies. ...
Article
Full-text available
Introduction Hallux valgus (HV) is one of the most prevalent forefoot deformities, and its frequency increases with age, reaching nearly 23% in adulthood (females are usually more affected). Studies on customised insoles and orthoses for HV showed inconclusive results. There is no consensus in literature regarding the ideal insole or length of use for pain relief or functional improvement in individuals with HV. This study will assess the effects of a customised insole with retrocapital bar associated with an infracapital bar of the first metatarsal on pain and function of individuals with symptomatic HV. Methods This is the protocol for a blinded, sham-controlled randomised clinical trial. Eighty participants with symptomatic HV will be randomised into two groups (40 per group): customised insole or sham insole. Assessments will be performed at baseline (T0), six (T6) and 12 weeks (T12) of intervention. A follow-up will occur after 4 weeks of intervention (T16). The primary and secondary outcomes will be pain (Numerical Pain Scale) and function (Foot Function Index), respectively. Statistical analysis Analysis of variance with a mixed design or Friedman’s test will be considered according to data distribution; post-hoc analyses will be performed using Bonferroni test. Time × group interaction and within-group and between-group differences will also be assessed. The intent-to-treat analysis will be used. A significance level of 5% and 95% s will be adopted for all statistical analyses. Ethics and dissemination This protocol was approved by the research ethics committee of the Faculty of Health Sciences of Trairi/Federal University of Rio Grande do Norte (UFRN/FACISA; opinion number 5411306). The study results will be disseminated to participants, submitted to a peer-reviewed journal and presented in scientific meetings. Trial registrations number NCT05408156 .
... 116 Moreover, custom-made silicone toe separator was reported to be comfortable to wear while reducing the hallux valgus angle. 117 Additionally, toe separators can help to stretch and strengthen the muscles in the feet and toes, which can help to improve overall foot function and reduce pain and discomfort. 115 It has been shown that silicone toe separator improves standing balance and walking balance in patients. ...
... One of the main disadvantages is that they can cause discomfort or irritation, especially if they are not properly fitted or if they are worn for extended periods. 117 Furthermore, in addition to the aforementioned advantages, there are also several potential drawbacks which have been described in Table 6. ...
... Some non-operative options are night splints, footwear modifications, shoe insoles, and physical therapy (Fraissler et al., 2016). More conservative non-surgical approaches are proper fitting footwear that have a wide and deep toe box, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, and muscle relaxants (Chadchavalpanichaya et al., 2017). Within the toe separator category of bunion correctors, there are cheaper prefabricated silicon toe separators (TS) on the market, but these boast lower effectiveness when compared to surgery. ...
... Consequently, they often do not fit the patients' feet very well, leading to some discomfort, which leads to patients being less likely to wear them. Custom-moulded TS have been researched and show good patient outcomes (Chadchavalpanichaya, 2017). ...
... Some non-operative options are night splints, footwear modifications, shoe insoles, and physical therapy (Fraissler et al., 2016). More conservative non-surgical approaches are proper fitting footwear that have a wide and deep toe box, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, and muscle relaxants (Chadchavalpanichaya et al., 2017). Within the toe separator category of bunion correctors, there are cheaper prefabricated silicon toe separators (TS) on the market, but these boast lower effectiveness when compared to surgery. ...
... Consequently, they often do not fit the patients' feet very well, leading to some discomfort, which leads to patients being less likely to wear them. Custom-moulded TS have been researched and show good patient outcomes (Chadchavalpanichaya, 2017). ...
... A custom-molded toe separator and a combined toe separator with a custom-molded insole are reported to help reduce pain and improve patients' abilities. 6,8 A toe sleeve is a silicone tube expanded to cover the bunion area and acts as a bumper between the bunion and the footwear. 12 Combined with the footwear modification, the toe sleeve can reduce compression and attrition between the footwear and the bunion, alleviating bunion pain as a result. ...
... The mean usage hours per week of both foot-toe orthoses were closed to the report by Chadchavalpanichaya et al. in the 3-month follow-up but after 3 months the adherence from their study was decrease. 8 Our study may need more follow-up time to evaluate the adherence in long term. ...
Article
Full-text available
Objectives: To compare clinical outcomes between using a pre-fabricated foot-toe orthosis, a toe sleeve and a toe separator in treating painful hallux valgus/bunion. Study design: A single-blinded randomized controlled trial. Setting: Ramathibodi Hospital, Bangkok, Thailand. Subjects: Patients with painful hallux valgus/bunion aged between 25 and 70 years old Methods: Patients were randomly divided into two groups: a toe separator and a toe sleeve group, both received the same treatment protocols. Primary outcomes were pain using a visual analog scale (VAS) and functions using visual analog scale-foot and ankle (VAS-FA) at one- and three-month follow-ups, and patient compliance with adherence to daily use of the orthosis as a secondary outcome. Results: Compared with the baseline, the mean VAS at one and three-month follow-ups statistically significantly decreased in both groups [the toe sleeve group: 55.72, 21.72 and 19.33 (p < 0.01); the toe separator group: 66.00, 42.67 and 42.17 (p < 0.01) respectively]. The mean VAS-FA at both follow-ups statistically significantly increased in both groups [the former toe sleeve group:75.89, 88.67 and 83.83 (p = 0.01), the toe separator group: 53.72, 65.33 and 71.17 (p < 0.01), respectively]. The toe sleeve group showed significantly lower VAS scores than the toe separator group at both follow-ups, whereas the VAS-FA did not differ. Conclusions: The toe sleeve significantly reduced pain better than the toe separator did in patients with hallux valgus at 1 and 3 months after usage. The VAS-FA also significantly improved in both groups without a significant inter-group difference. Both, a toe sleeve and a toe separator, improved functions.
... Toe separators are foot-toe orthoses designed to increase interdigital space, which can be between the 1 st and 2 nd phalanx [13] or between each of the toes [14]. This rehabilitation tool can be made of different materials and can be prefabricated or custom-made [15]. According to different investigations, toe separators have shown positive effects on correcting the position of the foot structure, relieving pain as well as increasing ROM, ankle stability, and balance [16,17]. ...
Article
Background and objectives: Injuries involving ankle stability and range of motion are among the most frequent in athletes and in the general population. In response, this study aimed to assess the immediate effects of toe separators on dynamic stability and ankle range of motion in healthy young individuals. Methods: Among the 68 eligible participants, 50 healthy and active subjects completed all trials. The impact of the intervention was evaluated using the Weight Bearing Lunge Test and Y-Test. The control condition performed the tests without toe separators, while the experimental condition performed the tests with toe separators. All participants performed both conditions with a wash-out period of at least 7 days between trials. Results: Statistical analysis revealed no significant differences in dynamic balance (p > 0.05) and range of motion (p > 0.05) between the two conditions. Additionally, no asymmetries were detected between the lower limbs in both tests (p > 0.05). Conclusions: The results of this pilot study indicate that using toe separators does not have an immediate effect on ankle range of motion and dynamic balance in young, healthy individuals. Future research should consider evaluating intervention programs of longer duration and exploring different populations.
... Selain itu, Hallux valgus splints, dan bunion pads, dapat digunakan untuk mengurangi gejala yang terjadi. Hallux valgus splint merupakan alat yang digunakan sebagai penanganan pada deformitas hallux valgus untuk meredakan nyeri, memperbaiki alignment, meningkatkan biomechanical function dan memperbaiki pola jalan (12). Splint menempatkan jari kaki ke posisi koreksi dengan harapan memungkinkan adaptasi jaringan lunak, meredakan nyeri dan menghambat terjadinya ruptur medial joint capsule dan collateral ligamen (13). ...
Article
Latar belakang: Karyawan perempuan di Pusat Perbelanjaan Modern tergolong sering menggunakan sepatu hak tinggi dalam bekerja, dimana hal ini sering menimbulkan masalah muskuloskeletal seperti timbulnya hallux valgus. Hallux valgus sangat menganggu para karyawan saat bekerja ditambah dengan posisi berdiri yang cukup lama. Kondisi ini terjadi apabila metatarsal pertama mengalami deviasi ke arah medial dan ibu jari kaki pertama mengalami deviasi ke lateral dengan rotasi, kondisi tersebut disertai dengan atau tanpa adanya pelebaran kearah medial dari jaringan lunak pada bagian distal metatarsal.Tujuan: Mengetahui pengaruh penggunaan Hallux Valgus Splint pada lama berdiri karyawan perempuan di Pusat Perbelanjaan Modern.Metode: Jenis penelitian ini adalah penelitian Pre-Ekperimental kuantitatif dengan one design pre test-post test. Subjek pada penelitian ini adalah karyawan perempuan di Pusat Perbelanjaan Modern Kota Solo sejumlah 20 orang yang dilaksanakan pada bulan Februari sampai Maret 2023. Teknik pengambilan sampel yang digunakan pada penelitian ini yaitu purposive sampling dengan menggunakan kriteria inklusi dan eksklusi. Instrumen yang digunakan pada penelitian ini adalah hallux valgus splint dan stopwatch untuk mengukur lama berdiri. Uji normalitas menggunakan uji Shapiro-Wilk dan Uji hipotesis menggunakan paired t-test. Hasil: Normalitas data menggunakan uji Shapiro wilk (<50), data berdistribusi normal dengan nilai signifikan 0, 659 dan 0,068. Uji hipotesis yang digunakan adalah paired sample t-test dengan nilai p = 0.000 (<0.05).Kesimpulan: Terdapat pengaruh penggunaan hallux valgus splint pada lama berdiri karyawan perempuan di Pusat Perbelanjaan Modern.
Article
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Introduction and objective: Hallux valgus is a common deformity (about 23%) in adult population. Deformation of the fist ray and pain causes gait pattern changes and lower life satisfaction. There are many suggestions how to treat bunion. The method of first choice is conservative treatment. One of the most popular option are orthoses of different kinds and functions. The aim of this article is to review the conservative methods of treatment and orthotic management of bunionsand its effectiveness. Materials and methods: PubMed and Google Scholar databases were searched. The criteria for qualifying the articles for the review were the following keywords: bunion, hallux valgus, orthoses, foot deformity. 21 articles from 2018 to 2023 were analyzed. Description of the state of knowledge: Conservative treatment includes orthoses, shoe modification, analgesics, and exercises. But the most popular are the first two methods. There are many types of orthoses used for hallux valgus, i.e. dynamic and static orthoses, separators, insoles and splints. Orthoses are used to reduce hallux valgus angle (HVA) and pain, and inhibit the progression of deformity in a long term. Studies show that dynamic orthoses have a greater effect on reducing HVA and pain compared to static orthoses. In addition, they are more frequently and willingly chosen by patients. Also, toe separators have a significant impact on minimizing pain and improving toe alignment. Summary: Significant reduction of pain and HVA are observed in both short-term and long-term effects when using dynamic orthoses and toe separators. Dynamic orthoses are also more likely to be chosen by patients for their convenience. However, all types of orthoses are beneficial to patients' well-being. A change of footwear also helps to stop the progression of the deformity and prevents recurrence after surgery.
Book
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Le ortoplastie (ortesi in silicone digitali e plantari) sono in evoluzione. Una revisione sullo stato dell'arte della tecnologia, della clinica, della metodologia riguardanti le ortesi in silicone in podologia: una revisione della letteratura critica (supportata da adeguato critical appraisal) ampliata dall'opinione di esperti. Biomeccanica dell'arto inferiore, lesioni cutanee acute e croniche al piede, amputazioni minori e maggiori, le prospettive ed i protocolli di utilizzo.
Article
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[Purpose] Hallux valgus is one of the most common deformations of the human foot, and it causes great difficulties for the patients. The aim of this paper was to review available medical literature in search of evidence which would justify implementation of physiotherapy, based on its effectiveness for patients with hallux valgus. [Subjects and Methods] The following databases were searched for applicable papers: PubMed, Google Scholar, Clinical Key and UpToDate. Full-text articles from the last 15 years were subjected to a review, which ultimately selected seven papers about hallux valgus therapy published over the past 12 years. These studies were grouped according to their design and level of evidence and classified depending on whether they concerned physiotherapy as postoperative therapy or as the only treatment. [Results] The studies included in the present analysis used the following interventions for patients with hallux valgus: exercise, manual therapy, gait training, taping and orthosis. All the studies showed beneficial effects and the most frequently observed results were reductions in pain and improvements in function. [Conclusion] The evidence found in the reviewed materials clearly indicates that patients with hallux valgus should not only be subject to surgical procedures but also undergo physiotherapeutic treatment.
Article
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Objective: To study the effect of night-time hallux valgus strap usage on decreasing the progression of hallux valgus angle. Methods: Patients, who were older than eighteen years old with moderate to severe degree of hallux valgus, were randomized into 2 groups: the study group (prescribed to use night-time hallux valgus strap for 8 hours per night for 12 months), and the control group. Patients in both groups were advised to have proper foot care with proper shoes. Results: There were 25 patients in the study group and 22 patients in the control group. No statistical difference was found in demographic data between both groups. The hallux valgus angle, which was obtained through radiographic measurement, was decreased in both groups. However, there were no statistically significant differences in the decrease of hallux valgus angle between the two groups (p>0.05). Conclusion: Prescribing to use night-time hallux valgus strap for 12 months cannot decrease the progression of the hallux valgus angle more than the control group.
Article
Aim: To determine the effects of taping and foot exercises on patients with hallux valgus. Materials and methods: The study included 20 female patients. The subjects were divided into 2 groups, the study and control groups. The study group was treated with taping and foot exercises, and the control group was treated only with foot exercises. A goniometer was used to determine the angle of hallux valgus. Foot pain intensity was assessed by the visual analog scale (VAS), and walking ability was evaluated using the walking ability scale (WAS). Results: At the end of the 8-week treatment period, a significant decrease was found in hallux valgus angle, resting pain, and walking pain in both groups (P < 0.05). Also, walking ability improved at least 1 grade in the study group. When the post-treatment results between the 2 groups were compared, the results were significantly different in favor of the study group with regard to decreased hallux valgus angle, resting and walking pain, and walking ability (P < 0.05). Conclusion: Our results suggest that a combined treatment program consisting of both taping and exercise had more beneficial effects than exercise alone on hallux valgus angle, foot pain, and walking ability in patients with hallux valgus.
Article
In an 11-year retrospective study of 45 patients (60 feet) with juvenile hallux valgus, a multiprocedural approach was used to surgically correct the deformity. A Chevron osteotomy or McBride procedure was used for mild deformities, a distal soft tissue procedure with proximal first metatarsal osteotomy was used for moderate and severe deformities with MTP subluxation, and a double osteotomy (extra-articular correction) was used for moderate and severe deformities with an increased distal metatarsal articular angle (DMAA). The average hallux valgus correction was 17.2° and the average correction of the 1–2 intermetatarsal angle was 5.3°. Good and excellent results were obtained in 92% of cases using a multiprocedural approach. Eighty-eight percent of patients were female and 40% of deformities occurred at age 10 or younger. Early onset was characterized by increased deformity and an increased DMAA. Maternal transmission was noted in 72% of patients. An increased distal metatarsal articular angle was noted in 48% of cases. With subluxation of the first MTP joint, the average DMAA was 7.9°. With a congruent joint, the average DMAA was 15.3°. In patients where hallux valgus occurred at age 10 or younger, the DMAA was increased. First metatarsal length was compared with second metatarsal length. While the incidence of a long first metatarsal was similar to that in the normal population (30%), the DMAA was 15.8° for a long first metatarsal and 6.0° for a short first metatarsal. An increased DMAA may be the defining characteristic of juvenile hallux valgus. The success of surgical correction of a juvenile hallux valgus deformity is intimately associated with the magnitude of the DMAA. Moderate and severe pes planus occurred in 17% of cases, which was no different than the incidence in the normal population. No recurrences occurred in the presence of pes planus. Pes planus was not thought to have an affect on occurrence or recurrence of deformity. Moderate and severe metatarsus adductus was noted in 22% of cases, a rate much higher than that in the normal population. The presence of metatarsus adductus did not affect the preoperative hallux valgus angle or the average surgical correction of the hallux valgus angle. Constricting footwear was noted by only 24% of patients as playing a role in the development of juvenile hallux valgus. There were six recurrences of the deformities and eight complications (six cases of postoperative hallux varus, one case of wire breakage, and one case of undercorrection).