Why ultrasound treatment is the best modality for lumbar disk herniated ?

Double spaced, Times New Roman 12 font, 1” margin. 

The assignment should be written in whole complete sentences in the third person.

Citation must be AMA

Point of view of why you think your modality is the best to treat lumbar disk herniated.

On the first page write  the title (Ultrasound on Lumbar Disk Herniated)

Please the paper has to have the references, remember is AMA style.

Ebadi et al. BMC Musculoskeletal Disorders 2012, 13:192
http://www.biomedcentral.com/1471-2474/13/192

RESEARCH ARTICLE Open Access

The effect of continuous ultrasound on chronic
non-specific low back pain: a single blind
placebo-controlled randomized trial
Safoora Ebadi1*, Noureddin Nakhostin Ansari1, Soofia Naghdi1, Shohre Jalaei1, Mirmostafa Sadat2, Hosein Bagheri1,
Maurits W vanTulder3, Nicholas Henschke4 and Ehsan Fallah5

Abstract

Background

: Non-specific chronic low back pain (NSCLBP) is one of the most common musculoskeletal disorders
around the world including Iran. One of the most widely used modalities in the field of physiotherapy is
therapeutic ultrasound (US). Despite its common use, there is still inconclusive evidence to support its effectiveness
in patients with NSCLBP. The objective of this study was to evaluate the effect of continuous US compared with
placebo US additional to exercise therapy for patients with NSCLBP.

Methods

: In this single blind placebo controlled study, 50 patients with NSCLBP were randomized into two
treatment groups: 1) continuous US (1 MHz &1.5 W/cm2) plus exercise 2) placebo US plus exercise. Patients received
treatments for 4 weeks, 10 treatment sessions, 3 times per week, every other day. Treatment effects were assessed
in terms of primary outcome measures: 1) functional disability, measured by Functional Rating Index, and 2) global
pain, measured by a visual analog scale. Secondary outcome measures were lumbar flexion and extension range of
motion (ROM), endurance time and rate of decline in median frequency of electromyography spectrum during a
Biering Sorensen test. All outcome variables were measured before, after treatment, and after one-month follow-up.
An intention to treat analysis was performed. Main effects of Time and Group as well as their interaction effect on
outcome measures were investigated using repeated measure ANOVA.

Results

: Analysis showed that both groups had improved regarding function (FRI) and global pain (VAS) (P < .001). Lumbar ROM as well as holding time during the Sorensen test and median frequency slope of all measured paravertebral muscles did not change significantly in either group (P > .05). Improvement in function and lumbar
ROM as well as endurance time were significantly greater in the group receiving continuous US (P < .05).

Conclusions

: The study showed that adding continuous US to a semi supervised exercise program significantly
improved function, lumbar ROM and endurance time. Further studies including a third group of only exercise and
no US can establish the possible effects of placebo US.

Trial registration: NTR2251

Keywords: Low back pain, Ultrasound, Functional disability, Pain, Muscle endurance, Range of motion

* Correspondence: s_ebadi@razi.tums.ac.ir
1Department of physiotherapy, School of Rehabilitation, Tehran University of
Medical Sciences, Shahnazari St, Tehran, Iran
Full list of author information is available at the end of the article

© 2012 Ebadi et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited.

mailto:s_ebadi@razi.tums.ac.ir

http://creativecommons.org/licenses/by/2.0

Ebadi et al. BMC Musculoskeletal Disorders 2012, 13:192 Page 2 of 10
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Background
Low back pain (LBP) is a major cause of morbidity
in high, middle and low-income countries and affects
80–85% of people over their lifetime [1]. LBP is a com-
mon health and socioeconomic problem in Iran. In a
cross-sectional study in one of the largest car-
manufacturing companies in Iran, the 1-year prevalence
of self reported LBP was 21% (20% for males and 27%
for females). The prevalence rate of absence due to LBP
was 5% per annum [2]. As part of a World Health
Organization study, LBP was detected in 15.4% of the
population under survey in Tehran (urban area) [3] and
in 23.4% of the population in rural areas in Iran [4].
Specific back pain occurs in approximately 2% of all

patients with back complaints [5]. For the majority of
patients with LBP a specific diagnosis cannot be defined
on the basis of anatomical or physiological abnormal-
ities. Non-specific LBP (NSLBP) is assumed to be in-
flammatory or mechanical in nature [6]. Chronic NSLBP
refers to an episode of activity-limiting LBP (with no
pain referred into either lower limb) that lasts for 3
months or more [7].
Non-pharmacological methods including a variety of

physical agents are the cornerstone of the management
of chronic LBP. Therapeutic ultrasound (US) is among
the commonly used physical modalities for treating soft
tissue injuries [8]. There is a dearth of evidence for the
clinical use of therapeutic US in patients with LBP [9].
Therapeutic US is delivered in two modes: 1) Continu-

ous mode in which the delivery of US is non-stop
throughout the treatment period; 2) Pulsed mode in which
the delivery of US is intermittently interrupted [10].
Therapeutic effects of US are classified as thermal and

non-thermal. Ultrasonic energy causes soft tissue mole-
cules to vibrate from exposure to the acoustic wave. This
increased molecular motion generates frictional heat and
consequently increases tissue temperature. This increased
temperature, named thermal effects, is thought to cause
changes in nerve conduction velocity, increase in enzym-
atic activity, changes in contractile activity of skeletal mus-
cles, increase in collagen tissue extensibility, increase in
local blood flow, increase in pain threshold, and reducing
muscle spasm [11].
Acoustic waves cause normally present minute gas

pockets in the tissue to develop into microscopic bubbles
or cavities. With therapeutic US, stable acoustic cavita-
tion results, whereby the microbubbles pulsate without
imploding. This pulsation leads to microstreaming of
fluid around the pulsating bubbles. When occurring
around cells, this process, referred to as non-thermal
effects, is reported to alter cell membrane activity, vascu-
lar wall permeability, and facilitate soft tissue healing
[12]. Traditionally, continuous US is used for its thermal
effects. Pulsing the US is thought to minimize its thermal

effects [10]. In fact, it is not possible to truly isolate the
thermal and non-thermal effects as both effects occur
with US application [13].
Studies on the efficacy of continuous US in chronic

LBP are lacking [8] and there is little evidence of its ef-
fectiveness in physiotherapy practice [14,15]. However,
lack of evidence is not evidence of lack of effect. There-
fore, the main objective of the current study was to
compare the effect of continuous US to placebo US
combined with exercise therapy on the primary out-
comes, functional status and pain of a group of patients
with NSCLBP, as well as on the secondary outcomes, en-
durance of paravertebral and hip muscles, and lumbar
range of motion.

Methods
Study design
The protocol of this study was approved by the Research
Council of Rehabilitation Faculty and the Ethical com-
mittee of Tehran University of Medical Sciences
(TUMS). The trial was registered with the Netherlands
Trial Registry (NTR2251). A more detailed description
of the study protocol has been published before [16].
Inclusion criteria in this study were as follows: 1) hav-

ing NSCLBP, 2) age between 18 and 60. Exclusion criteria
were: 1) having nerve root symptoms, 2) having systemic
disease and specific conditions such as neoplasm, frac-
tures, spondylolysthesis, spondylolysis, spinal stenosis,
ankylosing spondylitis, previous low back surgery, 3) tak-
ing medication for specific psychological problems, and
4) being pregnant. Patients were recruited from three
university hospitals of TUMS in Tehran, Iran. Patients
were provided with oral and written information about
the study and were asked to sign a consent form.

Sample size
The primary outcome measure of this study was changes
in functional status using Functional Rating Index (FRI).
Assuming the effect size of .8 for FRI with alpha set
at .05 and a power of .8, and accounting for 10% drop-
outs, the sample size needed was calculated as being 23
patients in each group.

Randomization
Randomization was performed using opaque sealed
envelopes, which were prepared by a statistician using a
computer generated randomization schedule. Half of the
envelopes were allocated to each group ensuring equal
number of subjects in each group.

Interventions
The intervention group received continuous US plus
semi-supervised exercise; the control group received pla-
cebo US plus semi-supervised exercise. Patients were

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requested not to take pain medications during the inter-
vention period and not to participate in any other exer-
cise or treatment program. All patients in both groups
received 10 sessions of treatment, three times a week,
every other day.

US therapy
Recent reviews of therapeutic US have failed to identify
a dose–response relationship [17-19]; though intensities
from 0.5 W/cm2 to 3 W/cm2 have been advocated [18].
Recently published randomized controlled trials, which
have reported significant benefits of therapeutic US over
placebo US, have used intensities of 1 W/cm2 to 1.5
W/cm2 [20,21].
Mild heating in the chronic phase of injury is known

to reduce pain and muscle spasm and to promote heal-
ing process. More chronic lesions are treated with con-
tinuous US. US frequency of 1 MHz is preferable when
treating large and deep soft tissue volumes. Intensities
between .8 to 3 W/cm2 are suggested for chronic lesions
[10,22,23]. Therefore, we chose continuous mode with a
frequency of 1 MHz and an intensity of 1.5 W/cm2 due
to the chronocity of the condition and the deep position
of lower back musculature.
US was applied using Enraf Nonius Sonoplus 434,

ENRAF,Netherland (coupling gel: Sono Gel, Germany).
Slow circular movements were applied using the trans-
ducer head over the painful paravertebral low back re-
gion. The duration of US was estimated for each patient
using Grey’s formula [24]. The average local exposure
time was planned to be one minute and the effective ra-
diating area of the transducer head was 5 cm2. For a pa-
tient with an area of low back pain of 40 cm2, for
example, the required total treatment time was: 1 min ×
(40 cm2/5 cm2) = 8 minutes.
Patients in the intervention group received continuous

US. Placebo US was delivered according to Hashish
et al. [25]. The therapist moved the applicator at the
same rate and pressure as for the continuous US group.
The machine and the light-emitting diode which sig-
naled that its power was connected were in view of the
subject, but the dials which indicated the US were out of
sight. Commonly, the patient is not aware of what she/
he should expect at the beginning of treatment with US
and since even with real US subjects are unaware of any
sensation at most therapeutic intensities [22], patients
were told in both groups that they may feel some heat
and should this cause discomfort, to notify the therapist
in order to safeguard patients in the continuous US
group from overheating.

Exercise therapy
There is strong evidence that exercise is as effective as
other conservative treatments in chronic LBP, and

functional and pain outcomes significantly improves in
groups receiving exercises relative to other interventions
[26]. Studies indicate that stretching and strengthening
exercises can improve pain and function. Home exer-
cises combined with therapist supervision have been
identified as the most effective strategy for patients with
CLBP [27].
It is recognized that the abdominal muscles, back

extensors, and gluteals are weak in patients with CLBP,
which can cause significant spinal loading. Patients with
LBP also exhibit tightness of hamstring and hip exten-
sors, which may impair spinal mechanics. Therefore,
strengthening and flexibility exercises are important for
a healthy lower back [28].
A semi-supervised exercise program was developed.

The program included posterior pelvic tilts, sit-ups,
bridging, quadruped exercises, and posterior hip and
knee muscles stretching [29,30]. Patients were instructed
to perform 2 to 3 stretches (of all muscles) per day and
hold the stretch for 20 seconds unless it hurts. Strength-
ening exercises started with 5 repetitions and progressed
according to each patient’s improvement, to 3 sets of 10
repetitions. Patients received a pamphlet describing
exercises with figures. To emphasize correct perform-
ance of the exercises at home, all exercises were checked
by the therapist on each treatment session.
Patients were asked to perform the exercises daily; the

stretching exercises before the strengthening exercises.
They were advised to stay active during the day, and
walk for at least 15 minutes before exercising, which
could also act as a warm-up. After completion of all
treatment sessions, patients were asked to maintain the
daily home exercises for one further month. During
the period from the completion of the treatment to the
follow-up measuring session (1 month), patients visited
the clinic once a week to control their exercises for cor-
rect performance.

Outcome measures
Primary and secondary outcome measures were docu-
mented at baseline, after the final treatment session
(after 4 weeks), and at one-month follow-up.
Pain and function are the two most fundamental clin-

ical outcomes for low back pain [31], while accurate as-
sessment of lumbar range of motion has been
recommended as a core domain in the evaluation of
patients with lumbar dysfunction and monitoring treat-
ment progress [32,33]. Since the endurance of trunk
muscles has been shown to be related to the incidence
of low back pain, surface electromyography, specifically
power spectral analysis of EMG signals has become an
increasingly common method for the assessment of lum-
bar muscle activity and localized muscle fatigue and has
been suggested as an objective, safe, easy and non

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invasive measure for the evaluation of patients with low
back pain [34].
Readers are referred to the design article of this study

for further details on assessment methods related to out-
come measurements [16].
The Primary outcomes were functional disability mea-

sured by the Persian version of the Functional Rating
Index (FRI) [35-37] and pain intensity measured during
last week on a 100 mm visual analogue scale (VAS) [38].
Secondary outcome measures were paravertebral

muscle fatigue during a Biering-Sorensen test using sur-
face electromyography [39], and lumbar flexion and ex-
tension range of motion using the Modified-Modified
Schober Test (MMST) [40].
Briefly, electromyographic data acquisition was per-

formed using an 8-channel surface EMG recorder
(DATA Log Biometrics Ltd) and analyzed by the built in
software, DATA LOG PC software version 7.5 (Biomet-
rics Ltd, UK). The software applied Fast Fourier trans-
formation to calculate median frequency and gave the
rate of decline in median frequency (MF slope) by trend
lines which were calculated using Linear Regression
Analysis based upon the least squares method to pro-
duce a slope m and an intercept of the Y-axis. Preampli-
fied bipolar Ag-AgCl electrodes (Type NO.SX230,
Biometrics Ltd, UK, 10 mm in diameter) with fix center
to center inter electrode distance of 20 mm were used.
The signal was gathered at a sample rate of 1000 Hertz
and a gain of 1000 Decibel.

Data analysis
All data were analyzed using SPSS V19, SPSS Inc.,
Chicago, IL, USA. Kolmogorov-smirnov test revealed
normal distribution of data. Repeated measure ANOVA
was used to determine the main and interaction effects
of Time and Group on the outcome measures. Bonfer-
roni test was used for pos -hoc analysis when necessary.
An intention-to-treat analysis of the data was per-

formed to retain data for all patients. In the case of
dropouts, the last recorded values for the outcome mea-
sures were used in the analysis (Last Observation Car-
ried Forward (LOCF)). p-values ≤ .05 were considered as
statistically significant.

Results
Figure 1 shows a flow chart of participants. A total of 50
patients were randomized, 25 to each group. One patient
in each group dropped out after the 9th session, because
of personal reasons. Nine more patients (3 patients in
the experimental group and 6 patients in the placebo
group) did not complete the follow-up measurement,
because of travelling, complete improvement or other
personal reasons.

Mean age of all participants was 34.7 (SD 12.6) years
with a mean pain history of 7.0 (SD 4.6) years. There
was no statistically significant difference in baseline
characteristics as well as baseline outcome measures be-
tween groups except for endurance time (Table 1). Pos-
sible effect of endurance time at baseline was measured
by evaluating the effect of adding this variable to the
model using analysis of covariance (ANCOVA). It
resulted in no change in the statistical significance of the
Time or Group effects.
Mean values for baseline, after 10 session treatment

and 1-month follow up measurements as well as
P values for baseline differences are shown in Table 2.
As can be seen, FRI has shown improvement (decreased)
in both groups. Also, VAS scores have dropped in both
groups. Details of secondary outcome measures can be
found in Table 2.
Table 3 details the results of the mixed model ANOVA

[Group (US and placebo US) × Time (Pre, Post, and fol-
low-up)] showing the effect of continuous US versus
sham US on outcome measures.

Primary outcome measures
There was a significant effect of Time (p < .001) on FRI. Bonferroni post-hoc test revealed that FRI scores had improved significantly after 10 treatment sessions (p < .001) and over time after one month follow-up in both groups (p < .001). The improvement of FRI scores was maintained one month after the end of the 10th

treatment session (p = .24). Main effect of Group on FRI
was significant (p = .004) while the Time × Group inter-
action was not significant (p = .31).
There was a significant effect of Time on VAS

(p < .001). The mixed model ANOVA on VAS did not reveal a statistically significant Group effect (p = .48). Post-hoc analysis showed that VAS scores improved sig- nificantly from baseline to after the 10th session (p < .001) and continued to improve until the one-month follow-up measurement (p = .004). The Time × Group interaction was not significant (p = .48).

Secondary outcome measures
Main effect of Time was not significant on both flexion
(p = .09) and extension lumbar ROM (p = .11). However,
a significant Group effect was identified for flexion
(p = .02) and extension (p = .01). The interaction effect
of Time × Group on lumbar range of motion was not
significant (flexion: p = .23, extension: p = .21).
The values for median frequency slope did not show a

statistically significant Time effect (p > .05); Group effect
(p > .05) or Group × Time interaction (p > .05).
Although main effect of Time on holding time during

Sorensen test was not significant (p = .09), the effect of
Group showed statistical significance (p = .01). There

Assessed for eligibility (n = 56)

Excluded (n = 6)
• Not meeting inclusion criteria (n = 4)
• Declined to participate (n = 0)
• Other reasons (n = 2)

Analysed (n = 25)
• Excluded from analysis (n = 0)

Lost to follow-up (didn’t attend the follow up
measurement session because of personal reasons
other than not being satisfied with the treatment)
(n = 3)

Allocated to continuous US group (n = 25)
• Received allocated intervention (n = 24)

• Did not receive allocated intervention (n = 1)
(Discontinued intervention after session 9th
(travelling))

Lost to follow-up (didn’t attend the follow up
measurement session because of personal reasons
other than not being satisfied with the treatment)
(n = 6)

Allocated to placebo US group (n = 25)
• Received allocated intervention (n = 24)

• Did not receive allocated intervention (n = 1)
(Discontinued intervention after session 9th
(travelling))
Analysed (n = 25)
• Excluded from analysis (n = 0)

Allocation

Analysis

Follow-Up

Randomized (n=50)

Enrollment

Figure 1 Flow diagram of participation and withdrawals for patients in continuous ultrasound and placebo ultrasound groups.

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was no interaction effect of Time × Group on this
parameter.

Discussion

In everyday clinical practice the application of US is
often combined with other physiotherapeutical interven-
tions, usually with exercise therapy [41]. The aim of this
study was to investigate whether continuous US can add
to the effects of exercise therapy in patients suffering
from NSCLBP compared to placebo US.
The results showed that both FRI and VAS have

improved after 10 sessions of treatment and over time

Table 1 Characteristics of patients with non specific chronic l
and placebo ultrasound groups

Parameter Continuous US*

(n=25)

Mean S

Age(years) 31.4 12

Onset since first episode(years) 5.8 4

BMI** 24.4 4

Sex 25%female _ 75%male

* Ultrasound.
** Body Mass Index.
***p values are for baseline differences between the two groups. Significance level

after 1 month in both groups. FRI improvement was sig-
nificantly greater in the group receiving continuous US.
This finding is consistent with Ansari et al. [20] who
demonstrated a better functional outcome in a continu-
ous US group in comparison with a placebo US group.
In their study patients did not receive any treatment in
addition to continuous and placebo US. Other rando-
mized trials in which the effect of US is directly com-
pared with placebo US in NSCLBP are lacking. US is
usually studied in comparison with other modalities
[42,43] or is presented in a package of physiotherapy
[44] and is also investigated in other subgroups of

ow back pain before treatment in continuous ultrasound

Placebo US P value***

(n=25)

D Mean SD

.3 37.4 11.9 .09

.1 8.1 4.7 .08

.1 25.3 3.5 .39

50%female _ 50%male

≤ .05.

Table 2 Mean and SD of primary and secondary outcome measures for continuous ultrasound and placebo ultrasound
groups at baseline, after 10 treatment sessions, and after 1 month follow up

Parameter Continuous US* Placebo US P value***

Before
treatment

After 10
sessions

After 1
month

Before
treatment
After 10
sessions
After 1
month

N=24 N=24 N=21 N=24 N=24 N=18

FRI** 40.8 (14.6) 23.4 (6.9) 22.8 (7.8) 43.9 (16.9) 31.1 (13.4) 30.5 (11.9) .49

VAS** 46.6 (17.7) 26.6 (13.8) 27.7 (14.4) 49 (16) 30.7 (13.1) 25.5 (9.9) .62

Flexion ROM (millimeters) 48.8 (19.4) 52.4 (18.6) 52.4 (19.60) 57.4 (18.9) 59.8 (17.9) 57.5 (18.3) .13

Extension ROM (millimeters) 19.4 (8.2) 20.12 (8.5) 21.7 (8.5) 23.6 (9.6) 24.1 (9.3) 24.7 (9.6) .11

Endurance time(in seconds) 111.5 (33.5) 128.9 (30.2) 128.3 (26.2) 134.2 (27.1) 140.3 (43.5) 139.3 (45.8) .01

Median frequency slope of right muscles

Illiocostalis lumborum -.24 (.17) -.21 (.09) -.19 (.07) -.21 (.13) -.20 (.06) -.19 (.06) .56

Multifidus -.26 (.15) -.26 (.16) -.24 (.13) -.30 (.17) -.25 (.05) -.24 (.05) .82

Gluteus maximus -.11 (.13) -.09 (.10) -.09 (.10) -.13 (.13) -.09 (.09) -.09 (.1) .65

Biceps femoris -.12 (.09) -.12 (.08) -.09 (.06) -.11 (.07) -.12 (.07) -.09 (.05) .83

Median frequency slope of left muscles

Illiocostalis lumborum -.18 (.11) -.18 (.11) -.16 (.09) -.21 (.12) -.19 (.07) -.18 (.08) .29

Multifidus -.24 (.14) -.25 (.15) -.25 (.15) -.29 (.21) -.24 (.10) -.25 (.11) .31

Gluteus Maximus -.06 (.04) -.06 (.06) -.08 (.05) -.09 (.07) -.08 (.05) -.09 (.08) .11

*US: Ultrasound.
**FRI: Functional Rating Index, VAS: Visual Analog Scale.
***p values are for baseline differences between the two groups at significance level ≤ .05.

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patients with LBP other than non-specific LBP, such as
lumbar disk herniation [45-47].
Durmus et al. [42] in comparing 3 groups of NSCLBP

patients who received US + exercise, Electrical Stimula-
tion (ES) + exercise and exercise only, showed signifi-
cantly greater improvement in pain and function of the
ES and US groups in comparison with the control group.
The study found no difference in function between
groups receiving either ES, or US but the US group had
significantly better scores regarding pain improvement.
Mohseni et al. [43] compared manipulation and exer-

cise treatment with US and exercise treatment in a ran-
domized clinical trial. One hundred and twenty patients
with chronic LBP were given a program of exercises. In
addition, one group received spinal manipulation ther-
apy and the other group received therapeutic US. Pain
intensity, functional disability, lumbar movements mea-
sured by Modified Modified Schober Test and muscle
endurance were measured shortly before treatment, at
the end of the treatment program and 6 months after
randomization using surface electromyography. Al-
though improvements were recorded in both groups,
patients receiving manipulation/exercise showed a
greater improvement compared with those receiving US/
exercise at both the end of the treatment period and at
6-month follow-up. The authors did not report on the
details of the exercise program, and US delivery was in-
consistent (continuous 1MHz, 1.5-2.5W/cm2 for 5 to 10

minutes, average 6 sessions, one or two times a week)
which could both be possible sources of difference with
our study.
Since the current study lacks a third group with no

US, it is impossible to explore the effects of exercise and
US separately except in parts where the continuous US
group has shown significant differences in comparison
to the placebo group. As both groups in our study
improved significantly regarding pain, we can conclude
that the treatment common to both groups (exercise
and mechanical application of US head) have attributed
to the outcome. There is strong evidence that exercise is
an effective treatment in chronic low-back pain [48]. Ex-
ercise programs for CLBP may be designed to reverse
deconditioning or the fear of movement associated with
pain. Such exercises typically include aerobic exercises
like walking as well as strengthening and stretching regi-
mens [27]. The specific exercises administered to
patients in this study may have been of benefit in im-
proving pain. Since many items of the FRI questionnaire
are indirectly related to the pain experienced by patients
during that specific task, the decreased pain achieved
with treatment could have caused the patients in both
groups to perform better during those tasks as well.
However, the individual role of the placebo effects of

US in the placebo group as well as the individual effect
of mechanical movement of US head and exercising in
both groups cannot be specified although each one may

Table 3 Main effects of Time and Group and their
interaction effect on primary and secondary outcome
measures (CI=95%,) *

Outcome measure Effects df F P value

FRI** Time 2 75.92 <.001*

Group 1 3.90 .004*

Time*Group 2 1.03 .31

VAS** Time 2 80.11 <0.001*

Group 1 .00 .48

Time*Group 2 .514 .98

Lumbar flexion Time 2 3.47 .09

Group 1 3.16 .02*

Time*Group 2 1.48 .23

Lumbar extension Time 2 1.53 .11

Group 1 4.12 .03*

Time*Group 2 1.61 .21

Endurance time Time 2 0.63 .43

Group 1 3.05 .05*

Time*Group 2 1.99 .17

Right Illiocostalis Lumborum Time 2 .39 .53

Group 1 .01 .93

Time*Group 2 .52 .41

Right Multifidus Time 2 .06 .16

Group 1 .16 .69

Time*Group 2 .52 .48

Right Gluteus Maximus Time 2 3.41 .73

Group 1 .02 .89

Time*Group 2 .52 .47

Right Biceps Femoris Time 2 5.38 .86

Group 1 .02 .79

Time*Group 2 .05 .82

Left IliocostalisLumborum Time 2 3.65 .06

Group 1 .87 .35

Time*Group 2 .38 .54

Left Multifidus Time 2 1.49 .23

Group 1 .14 .71

Time*Group 2 1.22 .27

Left Gluteus Maximus Time 2 .98 .33

Group 1 .95 .33

Time*Group 2 .86 .36

*The effect of the US versus placebo US on outcome measures was analyzed
using a Group (US and placebo US) × Time (Pre, Post, and follow-up) mixed
model ANOVA at significance level ≤ .05.
**FRI: Functional Rating Index, VAS: Visual Analog Scale.

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have played a part in the outcome. A placebo effect of
US can be the result of moving the applicator head thus
benefitting from the effects of massaging [20,25]. Con-
tinuous movement of the applicator may increase the

temperature of the area under treatment and may stimu-
late the skin receptors causing the pain gate control
mechanism to become active [20]. It has been shown
that moving the applicator of US on the affected area
can change the level of serum cortisol, which in turn can
affect inflammation and swelling [25]. Patients in both
groups could have benefitted from the Placebo effects of
the treatment [49].
A significant difference in the improvement of FRI

scores in favor of the continuous US group can be
related to the thermal and mechanical effects of continu-
ous US.
Morrisette et al. [50] showed that continuous 1 MHz

US given at either 1.5 W/cm2 or 2.0 W/cm2 intensity has
the capability of heating lumbar periarticular tissue while
the intervening muscle may heat as well. Morrisette sta-
ted that the temperature elevation was at a level thought
to be sufficient to produce the theoretical therapeutic
effects proposed with an elevation in temperature.
Regarding secondary outcome measures, although

lumbar flexion and extension ROM increased in both
groups after treatment, the increase did not reach statis-
tical significance within groups. Nevertheless, the
amount of improvement in ROM was significantly
greater in the continuous US group. Durmus et al. [42]
reported significant improvement in Modified Schober
scores in the group receiving US + exercise. However,
this improvement was not significantly different from
the two other treatment groups receiving ES + exercise
and exercise only. In the study carried out by Mohseni
et al. [43], lumbar flexion and extension ROM as mea-
sured by MMST (Modified Modified Schober Test)
improved significantly in US + exercise group but this
improvement was significantly lower in comparison with
the manipulation + exercise group. Though none of the
studies above, had reported the exact exercises pre-
scribed, their difference with our study can be possibly
explained by the differences in exercise type and inten-
sity and patient population as well as the difference in
the dosage of US.
Clinical assessment of movement impairment in low

back pain is predominantly done by measuring changes
in lumbar ROM in order to investigate patient’s response
to treatment [51]. The reduction in pain alongside
stretching and strengthening exercises prescribed could
have contributed to the increase of ROM in both groups.
The significant additional increase of ROM in the con-
tinuous US group may be due to the thermal and mech-
anical effects of continuous US. It has been shown that
temporary increases in range of movement can be pro-
duced by US treatment [52]. There is considerable evi-
dence that the extensibility of collagen based tissues will
change with ultrasound thermal applications as long as
sufficient temperature change is achieved [53]. Since the

Ebadi et al. BMC Musculoskeletal Disorders 2012, 13:192 Page 8 of 10
http://www.biomedcentral.com/1471-2474/13/192

therapeutic window for stretching following US applica-
tion is limited to some 3 minutes immediately after
treatment [54], our participants that performed exercises
after the treatment sessions, at home, barely could have
benefited from such thermal effect. Given that patients
suffering from chronic low back pain usually have spasm
[7], using continuous US could have been effective in
decreasing spasm [10] and consequently resulting in
greater ROM increase in comparison with placebo US.
Considering surface EMG parameters, no significant

effect of Time or Group was found on median frequency
slope of all measured muscles.
The assessment of fatigue based on SEMG techniques

during a fatiguing contraction can be demonstrated by a
trend of the power spectrum to lower frequencies usu-
ally measured by the decrease in median frequency. It
has been proposed that better endurance would exhibit
a less precipitous decay rate of the median frequency
[55], though conflicting opinions exist [56]. It has been
indicated that trunk muscle endurance can be increased
by using specific exercises [57].
Sung [58] investigated changes in multifidi muscle en-

durance and functional status after a 4-week supervised
spinal stabilization exercise program in 16 patients pre-
senting with chronic low back dysfunction (LBD).
Results showed that Oswestry scores improved signifi-
cantly from pre to post treatment. Significant pre- to
post treatment increase in multifidi muscle fatigue for
men coupled with a nonsignificant improvement in mul-
tifidi muscle endurance for women was also seen. Sung
[58] concluded that a 4-week spinal stabilization exercise
program significantly improved functional status in
patients presenting with LBD but the program was in-
sufficient to effect muscle fatigue. In another study,
Mohseni et al. [43] did not find any significant change in
median frequency slope or endurance time in the group
of patients with low back pain who received continuous
US plus exercise for an average of 6 sessions. We also
witnessed a nonsignificant change in MF slope of mea-
sured paravertebral muscles, which may imply that the
usefulness and sensitivity of this parameter was limited
in our study.
Regarding endurance time, the group receiving con-

tinuous US showed a significantly greater increase than
the placebo group. Traditionally, endurance is thought
of as the time for sustaining a nonstationary activity,
which ceases with fatigue [59]. One of the main reasons
for muscle fatigue is the accumulation of metabolite
wastes in the region and the inability of the system to
provide adequate blood circulation to supply oxygen to
the tissue and deplete it from wastes [60]. Additionally,
ischemia due to inflammation and spasm is a common
finding in chronic low back pain [7,28,61]. It is possible
that continuous US has improved low back muscle

fatigue by increasing blood circulation in the region and
helping improve blood supply [17,23,61] which in turn
have caused more sufficient and longer muscle contrac-
tion during the test.

Limitations
The main limitation of this study could be that the treat-
ing physiotherapist who collected the data was not
blinded to the group allocation. The number of dropouts
in our study was higher than what we had predicted at 1
month (22%). The self-reported compliance rate seemed
high, but it was not checked. The study lacks a third
group without US which makes it impossible to com-
ment on individual interventions separately.

Conclusions
This single blind, placebo -controlled, randomized clin-
ical trial showed that adding 1 MHz, 1.5 W/cm2 US to a
semi-supervised regimen of exercise had significantly
beneficial effects on function, lumbar flexion and exten-
sion ROM, and endurance time in patients with
NSCLBP.
Further studies including a third group of no US are

needed to explore the differential effects of each inter-
vention on patients with NSCLBP. In addition, it would
be helpful to measure other surface electromyography
parameters other than median frequency slope, such as
mean frequency, initial median frequency and normal-
ized median frequency slope to explore the possible
effects of the method used in this study on these
parameters.
Studies, in which the methodological shortcomings of

this study and similar studies are addressed, are needed
to verify a dose response relation in patients with
chronic low back pain.

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions
SE and NNA came up with the original concept for the study. SN, NH, and
MvT helped to design the study and contributed to the development of the
manuscript. EF and MS coordinated and referred the patients, HB
participated in the executive steps of the study and SHJ performed the
statistical analysis. SE wrote the first draft of the manuscript with help from
the other authors. All authors read and approved the final manuscript.

Acknowledgements

The authors would like to thank all patients included in this study. We would
also like to thank the Research Deputy, Tehran University of Medical Sciences
for their financial support.

Author details

1Department of physiotherapy, School of Rehabilitation, Tehran University of
Medical Sciences, Shahnazari St, Tehran, Iran. 2Sina Hospital, Medical Faculty,
Tehran University of Medical Sciences, Hasanabad St, Tehran, Iran.
3Department of Health Sciences, VU University, De Boelelaan, Amsterdam,
The Netherlands. 4Musculoskeletal Division NHMRC Postdoctoral Fellow, The
George Institute for Global Health, Kent St, Sydney, Australia. 5Emam Reza

Ebadi et al. BMC Musculoskeletal Disorders 2012, 13:192 Page 9 of 10
http://www.biomedcentral.com/1471-2474/13/192

hospital, Medical Faculty, Army University of Medical sciences of the I.R.Iran,
Etemadzade St., Tehran, Iran.

Received: 15 December 2011 Accepted: 26 September 2012
Published: 2 October 2012

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doi:10.1186/1471-2474-13-192
Cite this article as: Ebadi et al.: The effect of continuous ultrasound on
chronic non-specific low back pain: a single blind placebo-controlled
randomized trial. BMC Musculoskeletal Disorders 2012 13:192.

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Abstract
Background
Methods
Results
Conclusions
Trial registration
Background
Methods
Study design
Sample size
Randomization
Interventions
US therapy
Exercise therapy
Outcome measures
Data analysis
Results
Primary outcome measures
Secondary outcome measures
Discussion
Limitations
Conclusions
Competing interests
• Authors´ contributions

Acknowledgements
Author details
References

Clinical Study
Comparison of High-Intensity Laser Therapy and Ultrasound
Treatment in the Patients with Lumbar Discopathy

Ismail Boyraz,1 Ahmet Yildiz,1 Bunyamin Koc,1 and Hakan Sarman2

1Department of Physical Medicine and Rehabilitation Training and Research Hospital,
Abant Izzet Baysal University Medical School, Bolu, Turkey
2Department of Orthopeadic and Traumatology, Abant Izzet Baysal University Medical School, Bolu, Turkey

Correspondence should be addressed to Ismail Boyraz; boyraz@yahoo.com

Received 2 January 2015; Accepted 24 February 2015

Academic Editor: Vida Demarin

Copyright © 2015 Ismail Boyraz et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The aim of the present study was to evaluate the efficiency of high intensity laser and ultrasound therapy in patients who were
diagnosed with lumbar disc herniation and who were capable of performing physical exercises. 65 patients diagnosed with lumbar
disc were included in the study. The patients were randomly divided into three groups: Group 1 received 10 sessions of high intensity
laser to the lumbar region, Group 2 received 10 sessions of ultrasound, and Group 3 received medical therapy for 10 days and
isometric lumbar exercises. The efficacy of the treatment modalities was compared with the assessment of the patients before the
therapy at the end of the therapy, and in third month after the therapy. Comparing the changes between groups, statically significant
difference was observed in MH (mental health) parameter before treatment between Groups 1 and 2 and in MH parameter and VAS
score in third month of the therapy between Groups 2 and 3. However, the evaluation of the patients after ten days of treatment did
not show significant differences between the groups compared to baseline values. We found that HILT, ultrasound, and exercise
were efficient therapies for lumbar discopathy but HILT and ultrasound had longer effect on some parameters.

1. Introduction

The lumbar region is the most common site involved in
musculoskeletal pain. In developed countries, low-back pain
ranks second after headaches among the other causes of pain.
Of people living in industrialized countries, approximately
80% suffer from low-back pain at a certain time in their lives
[1]. Approximately 10% of people who experience low-back
pain develop chronic low-back pain. Approximately 1% of the
population is completely disabled due to low-back pain. Low-
back pain often starts at a young age, and the prevalence is
the highest in middle-aged population [1]. Intervertebral disc
diseases, which are an important etiological cause of low-back
pain, often occur in the lumbar region (61.94%). The majority
of people presenting with low-back pain have problems with
intervertebral discs. There are many different approaches
in the management of low-back pain. There is a wide
spectrum of treatment options including patient education,
behavioral therapies, lumbar support, and physical therapy
modalities such as massage, traction, superficial heaters, deep

heaters, transcutaneous electrical nerve stimulation (TENS),
and laser. The treatment of disc herniation is important to
control pain, to prevent the recurrence, and development of
chronic pain and disability, and to accelerate the return to
work process. Exercises and education on lumbar protective
measures have become prominent in recent years [2].

The term laser originated as an acronym for “light
amplification by stimulated emission of radiation.” The basic
principle of laser devices is the amplification of electron spin
rates by passing photon energy through a particular medium
to produce a single directional laser beam having a different
wavelength than the original light beam [3]. The action
mechanism of lasers is based on tissue stimulation. This
stimulation occurs at the level of the cell, vascular structure,
interstitial tissue, and immune system. Furthermore, laser has
direct effects when applied to the tissues locally and systemic
effects when applied to acupuncture points [4]. The analgesic
and anti-inflammatory effects of laser can be explained by
many mechanisms. Laser produces reactive vasodilation by
decreasing the pain sensation in the sensory nerve endings

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2 BioMed Research International

and the spasm in the muscle arterioles. It exerts analgesic
and anti-inflammatory effects by promoting regeneration
and increasing the release of beta-endorphins through the
induction of protein synthesis in the rheumatoid synovial
fluid. Laser is also suggested to stimulate hematopoiesis in the
bone marrow and exert antibacterial effects by stimulating
the immune system [4]. Lasers do not cause a significant
change in the tissue temperature. This finding indicates that
the potential physiological effects of laser are independent
from heat. Recent studies implicated laser in the regenerative
process of the tissue, bone formation, synthesis of new carti-
lage tissue, and synthesis of the cartilage matrix [5, 6]. It was
found that Nd: YAG lasers contribute to the healing process
in the tendons and ligaments and prevent the formation of
fibrosis [7]. Some studies showed that low level laser therapy
combined with exercise had more beneficial than exercise
alone in chronic low-back pain for the long term [8–10].

Superficial and deep heaters used in the treatment of
lumbar disc herniations have an important place in physical
therapy applications. Superficial and deep heaters have mul-
tiple effects such as vasodilation, increased pain threshold,
and increased collagen production in connective tissues. It
was found that ultrasound (US) exerts many effects mediated
by its thermal effects such as increase in nerve transmission
speed and enzymatic activity, increase in the contractility of
skeletal muscles, increase in the elongation of collagen tissue,
increase in blood flow rate, decline in pain threshold, and
relief of muscle spasms [11]. US is important physical therapy
agent used in the treatment of musculoskeletal disorders [12].

The aim of the present study is to evaluate the efficiency
of high intensity laser and ultrasound therapy in patients
who are diagnosed with lumbar disc herniation and who are
capable of performing physical exercises.

2. Materials and Methods

The present study included patients who were admitted
to the outpatient or inpatient clinic of Physical Therapy
and Rehabilitation at our hospital to undergo a physical
therapy program and who met the study inclusion criteria.
The diagnoses of the patients were established by medical
history, physical examination, and results of imaging studies.
The diagnose of 65 patients confirmed with lumbar MRI as
lumbar disc herniation. The patients were randomly divided
into three groups: Group 1 received 10 sessions of high
intensity laser to the lumbar region five sessions per week,
Group 2 received 10 sessions of US to the lumbar region five
sessions per week, and Group 3 received medical therapy
(NSAII) for 10 days and all of the patients in three groups
performed isometric lumbar exercises. The efficacy of the
treatment modalities was compared with the assessment of
the patients before the therapy, at the end of the therapy, and
in third month after the therapy.

The patients, who were diagnosed with lumbar disc her-
niation on lumbar MRI performed, who were not working on
occupations requiring intensive effort and in whom physical
therapy was not contraindicated, who did not have congenital
abnormalities or history of trauma, and who had sufficient
mental capacity to understand and answer the questions

asked in the assessment scales, were included in the study. The
patients who had a history of injection to the lumbar region
in the last four weeks or who had severe osteoporosis, history
of lumbar surgery, acute trauma, inflammatory pain, neuro-
logical disorder, or lumbar instability, patients who received
physical therapy in the last three months, and patients with
uncontrolled or severe cardiovascular or metabolic disorder
were excluded from the study.

A detailed medical history was obtained from the patients
and all underwent physical examination of the locomotor
system. The patients were randomly divided into three
groups: Group 1 included 20 patients, Group 2 included
25 patients, and Group 3 included 20 patients. VAS (visual
analog scale) was used to assess the pain level of the patients.
The Oswestry disability index, SF-36 (short form 36), was
used to evaluate the functional and psychologic status of the
patients. A locomotor system examination was repeated after
the therapy.

The patients in Group 1 received laser therapy 3.8 watts
for 14 minutes at a wavelength of 1064 nm. The total energy
received was 1800 joules. A cosmogamma Cyborg laser
device was used as the high intensity laser in this study.
This device produces laser beams with a wavelength of
1064 nm. This device is also known as a gallium aluminum
arsenide laser (GaAlAs laser) and designed to provide a fiber
output of at least 10 w (±10%). The device has continuous,
pulsed, and high pulsed modes. Different treatment programs
are recorded on the device memory according to different
diagnoses. The treatments were applied to the lumbar region
using beam expanders for the treatment of large areas up to
120 cm2.

The patients in Group 2 received a US therapy. A Chat-
tanooga intelect mobile US device was used in the treatments.
The intelect mobile US device allows the application of 1
or 3 MHz, and 20% or 50% or continuous modes without
any need to change the applicators. In the present study,
US was applied at 1.5 watt/cm for six minutes to the lumbar
paravertebral area. In addition, an isometric lumbar exercise
program was initiated to be performed with five repetitions in
each set (modified straightening and pelvic tilt exercises) in
Groups 1 and 2. The repetitions of both sets were increased up
to ten, provided that this did not increase the patient’s pain.

The patients in Group 3 received a medical therapy agent
for ten days in addition to two sets of lumbar isometric
exercises (pelvic tilt and modified straightening), which were
repeated five times in the morning and at night. All patients in
the study were trained on lumbar exercises. The patients were
administered pelvic tilt and modified straightening exercises,
to be performed in two sets, each containing at least five
repetitions during periods with intensive pain. The patients
were instructed to increase the number of repetitions to ten
in each set when the treatment provided some relief. The
patients were informed that the key to prevent recurrences
and provide functional recovery was making the exercises
part of their lives.

The demographic features of the patients were ques-
tioned. The patient’s age, place of residence, comorbid con-
ditions, and medications were questioned. The patients were

BioMed Research International 3

assessed before and after the therapy. The lumbar MR images
of the patients were evaluated.

Statistical Analysis. All statistical analyses were performed
using SPSS 17.0 for Windows (SPSS, Chicago, IL, USA). The
Kolmogorov-Smirnov test was used to test the normality of
the data distribution, and the data were expressed as the
mean and standard deviation. The chi-square test was used
to compare the categorical variables between the groups.
The one-way ANOVA test was used for comparisons of the
parametric continuous data. The Kruskal-Wallis test was used
for the nonparametric continuous data. Pearson’s correlation
analysis was used to examine the associations between the
variables, and a linear regression analysis was performed
to identify independent predictors of the pain domains of
the SF-36. A two-sided ? value < 0.05 was considered to be statistically significant. A repeated measures ANOVA was used to analyze the changes in variables. Significant differences were determined by Bonferroni post hoc tests.

3. Results

Of 20 patients in Group 1, 5 were males and 15 were females.
Of 25 patients in Group 2, 8 were males and 17 were females.
Of 20 patients in Group 3, 9 were males and 11 were females.
There was no statistically significant difference in terms of
gender distribution. The mean age was 58.4 ± 10.76 years in
Group 1, 61±10.47 years in Group 2, and 54.6±14.89 years
in Group 3. There was no significant difference between the
groups in terms of age (?> 0.05).

The lumbar MRI reports of 65 patients with lumbar disc
herniations were examined. Of these patients, 53 had disc
protrusion at one or more levels and 12 had disc extrusion.
Of 65 patients, 32 had compression of the nerve roots at one
or more levels. There was no significant difference in terms of
compression of the nerve root and level of disc herniation.

The comparison of parameters in Group 1 before the
treatment and at the end of the therapy revealed significant
changes in VAS (visual analog scale), Oswestry scale score,
BP (body pain), GH (general health), VT (vitality), and SF
(social functioning) (? < 0.05). There was no significant change in PF (Physical Function), RP (Restricted Physical Roles), RE (Restricted Emotional roles), and MH (Mental Health) parameters (? > 0.05). Changes of Oswestry scale
score and PF, BP, GH, and VT parameters in third month after
the therapy compared to values at the end of the treatment
were statically significant (Table 1).

The comparison of parameters in Group 2 before the
therapy and at the end of the therapy revealed significant
changes in VAS score, Oswestry scale score, and PF, RF, BP,
GH, VT, SF, RE, and MH parameters (?< 0.05). Comparing results in third month of the treatment and at the end of the treatment, statically significant changes were determined in Oswestry scale score and PF, BP, GH, and MH parameters (Table 1).

The comparison of parameters in Group 3 before the
therapy and at the end of the therapy revealed significant
changes is VAS, Oswestry scale score, and PF, RP, BP, GH, and
RE parameters (? < 0.05). VT, SF, and MH parameters did

not significantly change in Group 3 (? > 0.05). Comparing
results at the end of the treatment and in third month of
the treatment, statically significant change was continuing in
Oswestry scale score and BP and GH parameters (Table 1).

Comparing the changes between groups, statically sig-
nificant difference was observed in MH parameter before
treatment between Groups 1 and 2 and in MH parameter and
VAS score in third month of the therapy between Groups 2
and 3. However, the evaluation of the patients after ten days
of treatment did not show significant differences between the
groups compared to baseline values (Table 1).

4. Discussion

In the present study, a total of 65 patients with lumbar disc
herniation in the high intensity laser treatment (HILT), US,
and control groups were compared in terms of their scores
in VAS, SF-36, and Oswestry scale. In all treatment groups,
most parameters measured showed significant changes. The
differences in the three treatment groups did not achieve
statistical significance in terms of some parameters (? >
0.05). The comparison of parameters in Group 1 before
and at the end of the therapy revealed significant changes
in VAS score, Oswestry scale score, BP, GH, VT, and SF.
The comparison of parameters in Group 2 before and at
the end of the therapy revealed significant changes in VAS,
Oswestry scale score, and PF, RF, BP, GH, VT, SF, RE, and
MH parameters. The comparison of parameters in Group
3 before therapy and at the end of the therapy revealed
significant changes in terms of VAS, Oswestry scale score,
and PF, RP, BP, GH, and RE parameters. Improvement of
Oswestry scale score and PF, BP, GH, and VT parameters in
Group 1, improvement of Oswestry scale score and PF, BP,
GH, and MH parameters in Group 2, and improvement of
Oswestry scale score and BP and GH parameters in Group
3 were going on increasingly for three months. VAS scores
were better than compared to value before the therapy and at
the end of the therapy but there was no significant difference
between VAS scores in third month after the therapy and at
the end of the therapy.

Fiore et al. demonstrated the short term effects of a high
intensity laser on lumbar pain in a study that included 30
patients, 15 of which received US therapy and 15 who received
laser therapy. They reported more prominent pain relief and
recovery disability in the HILT group compared to US group
after three weeks of treatment. The rate of decline in the
VAS score in the two patient groups was 10% in favor of
the HILT group and 20% in Oswestry scale in favor of the
HILT group. They did not have control group as an important
lack of the study [13]. Alayat et al. conducted a randomized,
single-blind, placebo-controlled study to evaluate the long
term effects of HILT in patients with lumbar pain. The study
included 72 patients, and 28 patients in Group 1 received
HILT + exercise therapy, 24 patients in Group 2 received
placebo laser + exercise, and 20 patients in Group 3 received
HILT. They performed a total of 12 sessions of therapy for
four weeks. The patients were evaluated at baseline, fourth
week, and twelfth week. This study showed higher efficacy of

4 BioMed Research International

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BioMed Research International 5

the HILT + exercise program compared to placebo HILT +
exercise program and only exercise group [14]. Conte et al.
evaluated the HILT + lumbar school versus lumbar school
alone and studied 28 patients using VAS and Oswestry scale.
They emphasized that the HILT + lumbar school provided
higher improvement in Oswestry and VAS scores compared
to the lumbar school alone. Furthermore, they concluded that
the laser possessed low biological activity and produced little
side effects, if any, compared to pharmacological therapies
[15]. A meta-analysis of studies on low intensity laser therapy
reported positive effects on tissue repair and pain control
at various levels. However, these studies did not specifically
evaluate lumbar pain [16]. Monochromatic laser beams can
inherently modulate cellular and tissue functions. There
are controversial data regarding the effects of low intensity
laser on lumbar pain. Despite this controversy, low intensity
laser therapy has demonstrated efficacy in the short term
compared to the placebo when the patients were assessed
using VAS and Oswestry scales [17]. Considering last surveys,
HILT therapy can be good alternative physical therapy agent
for the patients with lumbar disc herniation. It does not
have distinct adverse effect and we did not encounter any
complication in our study.

Therapeutic US is an important treatment agent in mus-
culoskeletal disorders [12]. Ebadi et al. evaluated a total of 50
patients divided into two groups in order to investigate the
efficacy of continuous US in chronic lumbar pain. The first
group received continuous US and exercise, and the second
group received placebo US + exercise. They performed a total
of ten sessions of therapy for four weeks. They evaluated the
patients before and after the therapy using FRI (functional
rating index), VAS score, ROM, and endurance time. They
found significant improvement in the FRI index in the
continuous US group. The decrease in VAS scores, increase
in lumbar ROM, and endurance time were more prominent
in the continuous US group compared to the placebo US
group. The limitation of this study was that the effectiveness
of placebo US was not evaluated with the addition of a third
group that received exercise only [18]. Durmus et al. also
evaluated three patients groups that received either US +
exercise therapy, electrical stimulation, and exercise therapy
or exercise therapy alone for lumbar pain. They found that
US + exercise provided better pain relief compared to the
other two treatment modalities [19]. Doğan et al. divided 60
patients into three groups in order to evaluate three different
approaches in the treatment of chronic lumbar pain. In their
study, Group 1 received home exercises + aerobic exercise,
Group 2 received physical therapy (hot-pack, TENS, and US)
and home exercises, and Group 3 received home exercises
alone. They found a significant reduction in the pain level and
an increase in aerobic capacity, but there was no significant
difference between the groups. They stated that the rate
of functional disability and physiological disturbances were
lower in the physical therapy and home exercise group [20].
In the study by Grubisić et al. that evaluated the therapeutic
efficiency of US in the treatment of chronic lumbar pain,
16 out of 31 patients received US therapy. Ongoing medical
therapies of the study participants were not changed and
the patients were only allowed to take paracetamol during

painful periods. In the control group, a US device was
switched off while performing physical therapy. At the end
of the treatment period, US was found to be more effective
in providing pain relief; however, US was not found to
be superior to the control group in providing functional
improvement [21]. Basford et al. reported that US therapy has
gained a wide acceptance in routine practice in the treatment
of chronic lumbar pain; however, the evidence is not strong
enough to support the efficiency of this therapy [17]. US is
used for a long time in physical therapy and it is so safe and
effective treatment agent in several locomotor diseases. In our
study, we obtained improvement in terms of some parameters
in US group. We did not encounter any complication.

Limitation of this study may be the number of the
patients. If we received a larger numbers of patients, the effect
of HILT would be displayed obviously. We permitted the
patients to take medicine only during treatment period. It
may be seen disadvantage for the short term effect of the
treatment. Further studies with a larger number of patients
and controls are required to evaluate the long term effects of
the therapies.

There were no studies in the literature that compared the
effectiveness of HILT, US, and medical therapies in patients
with lumbar disc problems, which have an important place
in the etiology of acute and chronic lumbar pain. The current
literature search did not show a sufficient number of similar
studies. There are a very limited number of studies that
evaluated the efficiency of HILT in lumbar pain. The number
of patients included in the present study was similar to that
reported in other studies in the literature. The inclusion of a
control group allowed for the comparison of HILT and US
therapies with exercise therapies in the short term. However,
the evaluation of the patients aftermath ten-day treatment
did not show significant differences between the groups
compared to baseline values. This may have been caused
by the fact that the patients in our study were allowed to
take medical therapies during the most painful periods. The
patients in the HILT and US groups were not allowed to take
medical therapies unless they had extreme pain. We found
that HILT, US, and exercise were efficient therapies for lumbar
discopathy but HILT and US had longer effect in terms of
some parameters. Exercise therapy should never be ignored
to treat and prevent lumbar back pain.

Disclosure

All authors have no financial disclosures. They do not accept
any grants.

Conflict of Interests

The authors declare that there is no conflict of interests
regarding the publication of this paper.

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