The Role of Ultrasound Therapy in the Management of Musculoskeletal Soft Tissue Pain

Abstract

Ultrasound is an invaluable physical modality widely used for diagnosis and therapy in humans and animals. It is noninvasive, atraumatic, and may be used repeatedly. As a therapeutic tool, ultrasound has been in use for some 6 decades. Therapeutic ultrasound (TUS) is used for the treatment of musculoskeletal disorders, including acute soft tissue injuries, overuse syndromes, as well as chronic orthopedic and rheumatologic conditions. The aim of this review was to investigate the clinical effectiveness of TUS in musculoskeletal acute and chronic pain, mainly through the control of inflammation and the promotion of soft tissue injury healing. Based on the evidence presented, TUS is clinically effective in some musculoskeletal soft tissue pain conditions, but due to conflicting results in some studies, no specific positive recommendations can be made, nor does it permit exclusion of TUS from clinical practice. In phonophoresis, TUS plays a significant role, without reported adverse effects. There is scope for improving the evidence base with better designed studies.

Full text

https://doi.org/10.1177/1534734620948343
The International Journal of Lower
Extremity Wounds
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DOI: 10.1177/1534734620948343
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Original Review
Therapeutic ultrasound (TUS) is an electrophysical agent,
routinely used in physiotherapy for the treatment of painful
musculoskeletal conditions. Ultrasound (US) is an acoustic
energy with a frequency of 1.0 to 3.0 MHz and beyond,
which is above the upper threshold of human hearing, which
ranges from 16 Hz to 15 to20 000 Hz.1
The first biological effects of US were noted as early as
1917 by Langevin in fish,2 followed by Wood and Loomis,3
who reported erythrocyte lyses and reduced mobility in rats
following 300 kHz of US application. Therapeutic applica-
tion of US was introduced after 1930 in Germany and the
United States. TUS was first used to demonstrate in 1947
the treatment of painful muscle spasms in violin players,
and this triggered wide clinical applications as well as
research into the mechanisms of action.4 Technical develop-
ments in ultrasonic probe design as well in the firmware and
software to drive such a probe followed leading to the
acceptance of diagnostic US.
TUS has been used by physical therapists for the treat-
ment of injuries including ligament sprains, muscle strains,
tendonitis, joint inflammation, plantar fasciitis, metatarsal-
gia, facet irritation, impingement syndrome, bursitis, rheu-
matoid arthritis, osteoarthritis (OA), and scar tissue
adhesions.5 The aim of this report is to review the clinical
effectiveness of TUS as used in physiotherapy, to treat bone
and soft tissue lesions. It is essential to state that US is well
established and widely accepted as a diagnostic modality to
which no reference is made in this article, but which is the
subject of other articles within this issue.
Physiological Effects of Ultrasound
An US beam produces longitudinal waves with areas of
compression and rarefaction (Figure 1).6 US waves pass
through materials, creating oscillations of its particles;
such oscillations transfer the energy by compression and
rarefaction of the media. Similarly, when US passes
through the tissues it causes vibrations causing thermal
changes in the tissues.7
US may induce thermal and nonthermal physical effects
in the target tissues, and it is incorrect to assume that only
one effect is present at any time and that physical therapy
treatment may be classed as either thermal (continuous
mode) or nonthermal (pulsed mode, but rather a combina-
tion of the 2 phenomena.7
948343IJLXXX10.1177/1534734620948343The International Journal of Lower Extremity WoundsPapadopoulos and Mani
review-article2020
1Evaggelismos General Hospital, Athens, Greece
2Shanghai Jiao Tong University, Shanghai, China
Corresponding Author:
Emmanuel S. Papadopoulos, Evaggelismos General Hospital, 45-47
Ipsilantou Street, Kolonaki, Athens 10676, Greece.
Email: epapas2@gmail.com
The Role of Ultrasound Therapy in
the Management of Musculoskeletal
Soft Tissue Pain
Emmanuel S. Papadopoulos, MSc, PhD, SRP (UK)1
and Raj Mani, DSc, PhD, FACA, FIPEM, CCSci2
Abstract
Ultrasound is an invaluable physical modality widely used for diagnosis and therapy in humans and animals. It is noninvasive,
atraumatic, and may be used repeatedly. As a therapeutic tool, ultrasound has been in use for some 6 decades. Therapeutic
ultrasound (TUS) is used for the treatment of musculoskeletal disorders, including acute soft tissue injuries, overuse
syndromes, as well as chronic orthopedic and rheumatologic conditions. The aim of this review was to investigate the
clinical effectiveness of TUS in musculoskeletal acute and chronic pain, mainly through the control of inflammation and the
promotion of soft tissue injury healing. Based on the evidence presented, TUS is clinically effective in some musculoskeletal
soft tissue pain conditions, but due to conflicting results in some studies, no specific positive recommendations can be
made, nor does it permit exclusion of TUS from clinical practice. In phonophoresis, TUS plays a significant role, without
reported adverse effects. There is scope for improving the evidence base with better designed studies.
Keywords
therapeutic ultrasound, phonophoresis, musculoskeletal injuries, pain, soft tissue healing

2 The International Journal of Lower Extremity Wounds 00(0)
Thermal TUS effects include the following:
 Increased tissue temperature
 Hyperdynamic tissue metabolism
 Increased local blood flow
 Increased extensibility of collagen fibers
 Reduced viscosity of fluid elements in the tissue8
Nonthermal mechanisms include the following:
 Ultrasonic cavitation
 Gas body activation
 Mechanical stress or frequency resonance
nonthermalprocesses8
The 2 physiological mechanisms of US are interrelated
depending on the parameters of application. In the continu-
ous mode, the delivery of US is constant throughout the
treatment period, and in the pulsed mode, the delivery of
US is intermittently interrupted.9 The treatment parameters
of TUS that can be adjusted according to the patient pathol-
ogy are frequency, intensity, treatment mode (ie, duty
cycle), treatment duration, and treatment area. TUS fre-
quency of 3 MHz is used specifically for the treatment of
superficial tissues, whereas frequency of 1 MHz is applied
at deeper tissues,8 since there is an inverse relationship
between frequency and US energy penetration depth. It has
been reported that destructive effects of US energy, if any,
may be due to its mechanical rather than thermal effects.
Ultrasound Impedance
Impedance is a fundamental concept for the transmission/
reflection of US, being analogous to friction and move-
ment. The highest impedance (99.998%) is found in the
steel/air interface between the probe and the patient, which
can be overcome by using gel or water, since both are excel-
lent coupling media.10 US energy is better transmitted to the
tissues with a higher protein content (eg, tendons. liga-
ments, fascia, capsule, and scar tissue) and to a much lesser
extend to tissues with high water, low-protein content (eg,
blood, fat, cartilage, and bone).11,12
Clinical Applications of TUS
Physiotherapists use TUS for the management of acute and
chronic musculoskeletal pain (Figure 2).
Joint Pain
Therapeutic ultrasound is commonly used to treat joint
pain, which may be of capsular (arthritic) or noncapsular
origin.11 It was reported that TUS offers statistically signifi-
cant reduction in chronic pain on the knee, shoulder, or hip
when used alone or as part of a regime.12 In the treatment of
rotator cuff tendinopathy, it was argued that TUS combined
with low-level laser therapy was a beneficial adjunctive
treatment.13 There is less agreement on the treatment of
acute ankle sprains with a systematic review of 6 trials,
which showed no significant difference between TUS and
placebo. However, insufficient information on risk of bias
and intervention details were provided by the studies
included.14 Another systematic review of 47 trials (2388
Figure 2. Therapeutic ultrasound application, pulsed mode,
frequency: 3 MHz, intensity: 0.5 W/cm2, in lateral ankle sprain,
with a gel medium, and gentle, circular movements in order to
avoid local thermal discomfort.
Figure 1. Ultrasound compression and rarefaction. Adapted
with permission from Watson (2015).6

Papadopoulos and Mani 3
participants) found clinically important differences favor-
ing TUS over placebo at 6 weeks in terms of overall pain
(mean change = −14.9 vs −6.3 on a 52-point scale, mean
difference = −8.60, 95% confidence interval = −13.48 to
−3.72, 61 participants), and function, in people with calcific
tendinitis. However, TUS produced no clinically important
additional benefits when combined with other physical
therapy interventions.15 Combining TUS with other modali-
ties benefitted pain and function in a group with adhesive
capsulitis (N = 30) though again there were no significant
differences between the treatment and control groups16 and
this was broadly in accord with a double-blind randomized
clinical trial on N = 50 patients with primary adhesive cap-
sulitis.17 In another systematic review on the effectiveness
of physiotherapeutic interventions in treatment of frozen
shoulder/adhesive capsulitis, TUS was not recommended as
an effective treatment.18 In a recent randomized study, how-
ever, it was shown that low-intensity US resulted in statisti-
cally significant reduction of pain (P < .001) in patients
with upper trapezius myofascial neck and shoulder pain.
The authors suggest that TUS can be used to treat pain
related to upper trapezius myofascial trigger points, a com-
mon occurrence in patients with acute neck pain.19
There would appear to be some weak evidence to sup-
port the use of TUS in some joint pain conditions, either
singly or combined with a regime.
Plantar Fasciitis
The use of TUS to treat pain in plantar fasciitis is supported
by studies. In a recent pivotal study20 on N = 33 patients,
the use of intense TUS, an established US-based therapy, in
which sound waves were focused into a well-defined spe-
cific area of musculoskeletal tissue,20 resulted in significant
pain reduction at weeks 4, 8, 12, and 26 compared with
baseline (P < .001) at −39%, −49%, −51%, and −44%,
respectively. A concomitant reduction of fluid-filled cysts
(from −32% to −44%) was also observed. Foot function
index scores, a reliable assessment of tool of pain and func-
tion, also improved. There were no reported adverse effects
associated with TUS.
Another study, in N = 30 subjects with plantar fasci-
itis,21 low-level laser therapy was significantly more effec-
tive compared with US in pain numerical rating scale as
well as the Foot Ankle Ability Measure. In a systematic
review and meta-analysis,22 TUS led to reduction of plan-
tar fasciitis pain at 0 to 6 weeks but did not reach statistical
significance. In another randomized controlled trial
(RCT), the addition of 1 MHz continuous US, and stretch-
ing, led to significant reduction of plantar fasciitis pain,
with no significant difference compared with placebo and
stretching.23 In a RCT, US was found to be significantly
more effective than shockwave with regard to pain and
disability as determined by the Foot Function Index
scale.24 Last, in another study, TUS led to significant pain
relief (Visual Analogue Scale [VAS]), improved function,
and decreased plantar fascia thickness as measured from
magnetic resonance imaging scans in 60 patients with
chronic plantar fasciitis.25
These data permit the observation that TUS is effective
in pain reduction in plantar fasciitis, either used alone or as
part of a therapeutic regime. Details of TUS dose and
parameters were provided in most studies but not all accord-
ing to the guidelines on dose calculation (http://www.elec-
trotherapy.org/modality/ultrasound-dose-calculation).6
Low Back and Neck Pain
TUS is often used for the treatment of acute and chronic
neck and low back pain of musculoskeletal origin.8 In a
recent systematic review, it was shown that TUS was no
more effective than placebo to treat back pain, whereas it
resulted in significant neck pain reduction when combined
with other modalities.26 Similarly, in a systematic review,
US was shown to have short-term benefit only in improving
low-back function.27 The authors proposed further studies
to elucidate their findings. In another study, the combina-
tion of laser therapy, TUS, and exercise in N = 45 patients
with chronic neck and lower back pain (CNLBP) was effec-
tive in reducing pain and functional performance.28 These
studies suggest that TUS has a role to play in the manage-
ment of low back and neck pain.
Arthritis
The role of low-intensity pulsed US on cartilage healing in
knee OA was investigated in a review article of experimen-
tal studies, which showed that it can have a promising effect
on the cellular elements of the osteoarthritic articular carti-
lage and specifically on knee chondrocytes.29 In a critical
review, it was demonstrated that TUS was effective in
improving pain, function, and cartilage repair in knee OA.30
Later, in a systematic review and meta-analysis of low-
intensity pulsed US on knee OA a significant effect on pain
reduction and knee functional recovery was demonstrated.31
Similarly, in a systematic review in patients with knee OA,
it was shown that TUS led to statistically significant
improvement of pain (P < .01) and physical function (P <
.04), with the authors suggesting that it is a beneficial and
safe treatment for improving pain and function in patients
with knee OA.32 A single-blind controlled trial TUS was
equally effective as transcutaneous electrical stimulation
(TENS) in improving pain and function in 40 patients with
painful knee OA.33 In another RCT, which investigated the
effect of TUS on pain and physical function in N = 62
patients with knee OA, significant short-term improve-
ments were found in both variables.34 Additionally, in a sys-
tematic review and meta-analysis, it was found that both

4 The International Journal of Lower Extremity Wounds 00(0)
pulsed and continuous US were significantly more effective
in improving pain and function, when compared with the
control group.35 The efficacy of TUS on knee OA pain
reduction (difference in pain scores between US and control
of −1.2 cm on a 10-cm VAS) and function are also sup-
ported by previous studies.36,37 Another systematic review
concluded that hand US alone is effective in reducing joint
pain and improving grip strength, wrist dorsal flexion,
morning stiffness, and joint swelling in patients with rheu-
matoid arthritis.38 Overall, it can be concluded that US ther-
apy may significantly improve pain and function in patients
with OA and rheumatoid arthritis.
Sports Injuries
TUS is reported to have beneficial effects in sports injuries
pain relief, edema control, and range of joint motion,39 pos-
sibly by increasing pain thresholds, collagen extensibility,
reducing edema, and therefore inflammation, muscle
spasms, and joint stiffness. In a systematic review on acute
ankle sprains, it was concluded that TUS was no more
effective than placebo in treating pain and edema, with no
details of TUS parameters measurement techniques pro-
vided. A need for rigorous RCTs to demonstrate efficacy
was emphazised.14 Similar findings on ankle sprains were
found in another study described above with no detailed
information on treatment parameters.16
In a review of the rehabilitation of hamstring injuries, the
authors concluded that the efficacy of TUS in this condition
was controversial on account of the discord in relevant
research.40
TUS therapy was reported to be beneficial in treating
tendon injuries in an animal model.41,42 Admittedly these
observations were on acute injuries; nonetheless, the obser-
vations may have value in understanding TUS use on human
trials. Since TUS is clinically applied in the acute and sub-
acute stages of painful conditions, the above-mentioned
finding may explain the mechanism of action and the subse-
quent analgesic effect, which however needs to be estab-
lished by larger studies.
Lateral Epicondylitis
Several studies have been carried out to investigate the ther-
apeutic efficacy of TUS on lateral epicondylitis. A recent
meta-analysis of RCTs, which compared the long-term effi-
cacy of TUS with extracorporeal shockwave therapy in pain
relief and function,42 found that both techniques were effec-
tive; however, shockwave therapy was significantly more
effective in alleviating pain. Another RCT compared TUS
and exercise with corticosteroid injections in N = 49
patients with lateral epicondylitis, and the study found that
at 12 weeks, TUS and exercise resulted in statistically sig-
nificant improvement in VAS, PRTEE (Patient-Rated
Tennis Elbow Evaluation) pain score, PRTEE function
score, and pain free grip strength, compared with cortico-
steroid injections group (P < .001).43 Other reviews of TUS
use in the same condition showed benefits when used singly
or with friction massage44 or other physiotherapy tech-
niques.45 These reports lend support to the use of TUS to
treat painful, lateral epicondylitis. Positive overall effects of
TUS in lateral elbow pain are apparent but need to be fur-
ther clinically substantiated.
Soft Tissue Healing
According to the evidence presented so far, TUS can sig-
nificantly contribute to the reduction of musculoskeletal
pain, through the reduction of inflammation and the pro-
motion of all stages of soft tissue healing following tis-
sue injury.46,47 In a recent experimental study, it was
shown that low-intensity pulsed US therapy had a bios-
timulatory effect on fibroblast cells, confirming its thera-
peutic properties related to the initial phases of tissue
healing.48
Another experimental study was carried out in N =28
rats following tenotomy and re-suturing of calcaneus ten-
dons, where the experimental group was treated daily, with
a 5-minute 1 MHz, 0.1 W/cm2, TUS, and sham US was
applied to the control group. The results showed that the
experimental group had significantly higher load and ten-
sile strength, suggesting that TUS can enhance the healing
process of acute tendon rupture.49
In another experimental study,50 it was shown that the
application of low-intensity pulsed US accelerated patellar
bone-tendon junction healing through regulation of vascu-
lar endothelial growth factor expression and cartilage for-
mation in rabbits. In a study that combined low-intensity
pulsed US with 1.5 MHz frequency and functional electri-
cal stimulation, bone-tendon junction healing was acceler-
ated in a rabbit model.51 The same conclusion was drawn in
a similar study, which investigated the effects of low-inten-
sity TUS on medial collateral ligament acute injury healing
in the rabbit model and resulted in increased scar cross-sec-
tional area and type I collagen present at 6 weeks after
injury as compared with sham treatment.52 Finally, in a sys-
tematic review that examined the effect of low-intensity
TUS on soft tissue healing in animal models, it was shown
that it facilitated tendon healing, with increased tensile
strength and collagen alignment.53 It was also shown that
US enhanced cell proliferation during muscle regeneration
and improved tissue biomechanics in skeletal muscle and
ligament injuries (ultimate load, stiffness, and energy
absorption). US also promoted tendon-bone junction heal-
ing through improved tissue function. According to the
authors, these findings provide adequate scientific evidence
to explain the mechanism of soft tissue injury healing pro-
motion and pain reduction, through low-intensity US, and

Papadopoulos and Mani 5
improve outcomes for musculoskeletal injuries and postop-
erative recovery.
Phonophoresis
Phonophoresis is the migration of drug molecules, con-
tained in a contact agent, by US use through the skin, either
by structural changes that increase skin permeability, or
through convection-related mechanisms that occur only
when US is applied (Figure 3).54 US with 1 to 3 ΜΗz fre-
quency and 0 to 2 W/cm2 intensity, as indicated, has been
shown to be safe and increases percutaneous absorption in
animal models.55
Phonophoresis, compared with exercise, is reported to
be beneficial in reducing neck pain, which, according to the
authors, may be of value, in conjunction with other physio-
therapy interventions.56
Several clinical studies have been carried out investigat-
ing the role of phonophoresis in musculoskeletal painful
syndromes (Table 1). Ιn an RCT, the application of dexa-
methasone phonophoresis, TENS, and exercise (study
group) was compared with TUS, TENS, and exercise (con-
trol group), in N = 46 female patients with knee OA. The
experimental group resulted in a greater, statistically sig-
nificant improvement in pain (VAS: P < .001) and func-
tion in patients with knee OA than TUS combined with
exercise and TENS. The effect size of phonophoresis was
clinically significant.57 A study that compared phonophore-
sis, dry needling, and myofascial release in N = 60 patients
with upper trapezius neck pain showed that phonophoresis
and dry needling were significantly more effective (P <
s.001) in pain intensity than myofascial release.58 In a sin-
gle-blind study, where phonophoresis with TENS was
compared with phonophoresis alone, TUS and sham US
(control), in N = 100 patients with acute mechanical neck
pain and active myofascial trigger points, showed statisti-
cally significant improvements in postintervention pres-
sure pain threshold (algometer: an instrument measuring
the smallest pressure on the skin that will arouse a sensa-
tion of pain) and range of motion values in all treatment
groups (P < .0001).59 In an RCT phonophoresis was com-
pared with Mills manipulation and deep transverse fric-
tions in 60 patients with lateral epicondylitis, and it was
found that both treatments resulted in significant improve-
ment of pain and grip strength.60 Last, an RCT compared
phonophoresis and iontophoresis using dexamethasone
sodium phosphate in the management of 50 patients with
knee OA and found that both therapeutic modalities were
equally effective and well-tolerated.61 Similar findings
were demonstrated in a systematic review and meta-analy-
sis, examining the effects of TUS and phonophoresis in
patients with knee OA,62 and showed that although both
treatments reduced pain and improved function signifi-
cantly, phonophoresis was significantly more effective in
pain elimination, suggesting that it was successful in the
transmission of the pharmaceutical agent in the affected
tissues. An RCT showed that phonophoresis with diclofe-
nac and thiocolchicoside gel, was superior to US alone in
the treatment of low back pain.63
Last, in an RCT in 61 patients with chronic neck pain, it
was shown that phonophoresis and exercise was significantly
more effective than placebo and exercise alone in pain, dis-
ability, sleep quality, and depression measurements.64
According to the above study findings, it seems that that
there is adequate evidence to support the application of
Non Steroidal Anti Inflammatory Drugs (NSAIDs) via US
since it may lead to clinically significant therapeutic effects
in painful musculoskeletal conditions with no reported side
effects.65
Discussion
The aim of this review was to study the role of TUS in the
treatment of soft tissue pain conditions. In painful lateral
epicondylitis and arthritis the evidence favors the use of
TUS either singly or in combination with another technique.
In other common musculoskeletal pain conditions, there are
varying levels of evidence of TUS use to benefit pain. The
use of phonophoresis clearly benefits pain management in
certain soft tissue conditions. It is speculated that the bene-
fits of phonophoresis may be the result of driving molecules
of anti-inflammatory agent through the epidermis and this
together with the massaging effect of TUS may be causing
vasodilatation, and edema reduction. As a technique, TUS
is well-accepted and widely available: there is a skill in
using it that is transferable.
Clearly there is a role for TUS in managing pain even
though the evidence-based needs developing. Does TUS
Figure 3. Phonophoresis (diclofenac sodium) in shoulder
rotator cuff tendinitis.

6
Table 1. Characteristics of Studies in Phonophoresis Ultrasound Therapy.
Study Participants Treatment N Outcome measures Main results
Ahmed etal57 (2019) Female patients with knee
OA
Study group: Phonophoresis, TENS, and
quadriceps strengthening exercises
Control group: US, TENS, and exercise
46 Pain (VAS, WOMAC)
Function (Timed Up and Go
test and total WOMAC)
Significant improvement between experimental and control groups in
VAS and WOMAC subscale and function (P < .001)
Tabatabaiee etal58
(2019)
Patients with myofascial
trigger points in the
upper trapezius muscle
participated
Group 1: Pressure release
Group 2: Phonophoresis with betamethasone
Group3: Dry needling
60 Pain: VAS, pain threshold
algometer
Active cervical range of
motion
Significant pain decrease, active cervical range of motion, and pain
pressure threshold increase were observed in the 3 groups (P < .001).
The dry needling and phonophoresis groups reported more significant
improvement compared with the pressure release group (P < .001).
NS diff. between the dry needling and phonophoresis groups.
Takla and Rezk-
Allah59 (2018)
Patients with acute
mechanical neck pain and
myofascial trigger point in
the upper trapezius
Group 1: Diclofenac phonophoresis and TENS
Group 2: Diclofenac phonophoresis
Group 3: US
Control group: sham US
100 Pressure threshold
algometer
Active lateral cervical flexion
Statistically significant improvements in pressure pain threshold and range
of motion values in treatment groups (P < .0001).
Phonophoresis with TENS was superior over phonophoresis in pain
reduction (P < .0001).
Phonophoresis was superior over US in pain reduction.
Akinbo etal61 (2009) Adult patients with knee
OA
Group 1: Dexamethasone sodium phosphate
(DEX-P) phonophoresis (PH)
Group 2: 0.4% DEX-P iontophoresis therapy
50 WOMAC scores
20 m ambulatory time
knee range of motion
Significant improvement in both groups (P < .001)
NS diff. between groups
Wu etal62 (2019) Adult patients with knee
OA (systematic review
and meta-analysis of RCTs
on OA)
Randomized controlled trials comparing
therapeutic US with sham US and
phonophoresis with conventional US
1074 VAS, WOMAC, Knee ROM,
Lequesne index
TUS significantly reduced pain (P < .00001) and (WOMAC) physical
function score (P = .03) and increased ROM and Laseque index
Phonophoresis US illustrated significantly lower VAS scores compared
with TUS (P = .009)
Altan etal63 (2019) Adult patients with acute
low back pain
Group 1: US with diclofenac + thiocolchicoside
gel for 10 minutes and for a total of 10
sessions
Group 2: Therapeutic US with contact gel
protocol was applied with the same setting
and timing with group 1 using US gel that does
not contain any pharmaceutical ingredient
60 Visual numeric scale (VNS),
Oswestry Disability Index
(ODI), and Shober lumbar
flexion test
Significant improvement in both groups (P < .05)
Phonophoresis is statistically significant and more effective than TUS in
short-term ODI and in pain reduction long term
Abbreviations: US, ultrasound; OA, osteoarthritis; TENS, transcutaneous electrical stimulation; VAS, visual analogue scale; WOMAC, Western Ontario and McMaster University Osteoarthritis Index; NS, not significant; ROM,
range of motion; RCT, randomized-controlled trial.

Papadopoulos and Mani 7
offer any benefit in treating wound pain—which is an area
of interest to readers of this journal? US is used in wound
debridement, which reduces pain and benefits healing as
argued in another part of this issue: improving the under-
standing of TUS may have benefits for wound healers.
Among the other value of US is its portability, lending
itself to home care when offered by a trained physiothera-
pists/clinicians. This could become especially valuable
when home care is preferred to clinic visits as observed dur-
ing the current crisis resulting from COVID-19.
Additionally, there are no known reported adverse effects
of TUS application. Hence, it can be applied safely, either
alone or in conjunction with other techniques, taking of
course into account all indications and precautions as
described elsewhere.10
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) received no financial support for the research,
authorship, and/or publication of this article.
ORCID iD
Emmanuel S. Papadopoulos https://orcid.org/0000-0002-3414
-9685
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