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Article
Efficacy of low level laser therapy
associated with exercises in knee
osteoarthritis: a randomized
double-blind study
Patrı
´cia Pereira Alfredo
1
, Jan Magnus Bjordal
2
,
Sı
´lvia Helena Dreyer
1
, Sarah Ru
´bia
Ferreira Meneses
1
, Giovana Zaguetti
1
,
Vanessa Ovanessian
3
, Thiago Yukio Fukuda
3
,
Washington Steagall Junior
4
, Rodrigo A
´lvaro
Branda
˜o Lopes Martins
5
,
Raquel Aparecida Casarotto
1
and
Ame
´lia Pasqual Marques
1
Abstract
Objectives: To estimate the effects of low level laser therapy in combination with a programme of
exercises on pain, functionality, range of motion, muscular strength and quality of life in patients with
osteoarthritis of the knee.
Design: A randomized double-blind placebo-controlled trial with sequential allocation of patients to
different treatment groups.
Setting: Special Rehabilitation Services.
Subjects: Forty participants with knee osteoarthritis, 2–4 osteoarthritis degree, aged between 50 and 75
years and both genders.
Intervention: Participants were randomized into one of two groups: the laser group (low level laser
therapy dose of 3 J and exercises) or placebo group (placebo laser and exercises).
Main measures: Pain was assessed using a visual analogue scale (VAS), functionality using the Lequesne
questionnaire, range of motion with a universal goniometer, muscular strength using a dynamometer, and
activity using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) questionnaire at
1
Department of Speech Therapy, Physical Therapy and
Occupational Therapy, School of Medicine, Sa
˜o Paulo
University, Sa
˜o Paulo, Brazil
2
School of Health and Social Science, Institute of Physical
Therapy, Bergen University College, Bergen, Norway
3
School of Medical Science, Santa Casa de Miserico
´rdia, Sa
˜o
Paulo, Brazil
4
Department of Dentistic, School of Odontology, Sa
˜o Paulo
University, Sa
˜o Paulo, Brazil
5
Department of Pharmacology, Institute of Biomedical Sciences,
University of Sa
˜o Paulo, Sa
˜o Paulo, Brazil
Corresponding author:
Patrı
´cia Pereira Alfredo, Departamento de Fisioterapia,
Fonoaudiologia e Terapia Ocupacional. Rua Cipota
ˆnea, 51,
Cidade Universita
´ria, Sa
˜o Paulo (SP) 05360-160, Brazil
Email: patriciaalfredo@usp.br
Clinical Rehabilitation
26(6) 523–533
ÓThe Author(s) 2011
Reprints and permissions:
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DOI: 10.1177/0269215511425962
cre.sagepub.com
three time points: (T1) baseline, (T2) after the end of laser therapy (three weeks) and (T3) the end of the
exercises (11 weeks).
Results: When comparing groups, significant differences in the activity were also found (P¼0.03). No
other significant differences (P>0.05) were observed in other variables. In intragroup analysis, partici-
pants in the laser group had significant improvement, relative to baseline, on pain (P¼0.001), range of
motion (P¼0.01), functionality (P¼0.001) and activity (P<0.001). No significant improvement was seen
in the placebo group.
Conclusion: Our findings suggest that low level laser therapy when associated with exercises is effective
in yielding pain relief, function and activity on patients with osteoarthritis of the knees.
Keywords
Osteoarthritis, low level laser therapy, exercises, knee
Received: 18 May 2011; accepted: 15 September 2011
Introduction
Osteoarthritis is a rheumatologic disorder char-
acterized by pain, joint inflammation, impair-
ment of muscular stability and functional
incapacity. It is a primary cause of impaired
quality of life and is associated with morbidity
and increased mortality risk.
1
The most
common form of osteoarthritis affects the
knee, and its prevalence is secondary to longer
life expectancy and population ageing.
2
In Brazil, osteoarthritis is a cause of 7.5% of
all temporary absenteeism from work, as well as
of 6.2% of all illness-related retirements.
3
Although commonly seen as a progressive and
chronic disorder, the early therapeutic approach
can minimize its symptoms.
4
The European League Against Rheumatism
(EULAR) suggests that low level laser therapy
and exercises should be considered when plan-
ning optimal treatment for osteoarthritis.
2
Indeed, low level laser therapy induces photo-
chemical physiological actions in living tissues
at the cellular level. Some of these effects include
cellular oxygenation, release of neurotransmit-
ters associated with pain modulation and release
of anti-inflammatory, endogenous mediators.
5
Nonetheless, the clinical efficacy of low level
laser therapy in the treatment of osteoarthritis
is still debatable; while some authors have
reported pain relief,
6,7
others have not.
8,9
These discrepancies may be associated with the
parameters (wave length, dose, time, area, tech-
nique) used in treatments by different studies.
Thus it is necessary to define which parameters
should be used to achieve optimum therapeutic
response in patients with osteoarthristis.
Strong evidence suggests that joint exercises
reduce pain and disability in patients with oste-
oarthritis.
10
There is evidence that exercise is
responsible for muscular strengthening and
better flexibility, improved global function as
well as better performance of activities of daily
living (ADL).
11
The efficacy of low level laser therapy in the
treatment of osteoarthritis, as well as its associ-
ation with exercise therapy has previously been
questioned.
6–9
The aim of this investigation is to
evaluate the effectiveness of this low level laser
therapy and exercise in reducing pain, improving
functionality, range of motion (ROM) and qual-
ity of life (QOL) in an osteoarthritis population.
Methods
Participants
Participants were recruited from the Special
Rehabilitation Services in Taboa
˜o da Serra-SP
Brazil.
524 Clinical Rehabilitation 26(6)
To be included in the study, participants had
to have knee osteoarthritis with osteoarthritis
levels 2–4 according to Kellgren–Lawrence
grade,
12
be aged between 50 and 75 years, both
genders, have knee pain and functional disability
for at least three months, and according to the
criteria of the American College for
Rheumatology.
13
The Kellgren and Lawrence
grading of knee osteoarthritis is as follows:
none (0), doubtful (1), minimal (2), moderate
(3) and severe (4).
The ACR criteria of knee osteoarthritis are as
follows:
.Using history and physical examination: knee
pain and three of the following – over 50
years old; less than 30 minutes of morning
stiffness; bony tenderness; bony enlargement;
no palpable warmth of synovial.
.Using history, physical examination and
radiographic findings: knee pain and one of
the following – over 50 years old; less than 30
minutes of morning stiffness; crepitus on
active motion; and osteophytes.
.Using history, physical examination and
laboratory findings: knee pain and five
of the following – over 50 years old;
less than 30 minutes of morning stiffness;
bony tenderness; bony enlargement; no
palpable warmth of synovial; crepitus on
active motion; ESR <40 mm/h; rheumatoid
factor <1: 40; synovial fluid sign of
osteoarthritis.
Participants were excluded if they had cancer,
diabetes, symptomatic hip osteoarthritis, or used
antidepressants, anti-inflammatory medications
or anxiolytics during six months prior to
enrolment.
The study was approved by the Research
Ethics Committee and all participants signed
informed consent forms.
Randomization
Forty-six participants with osteoarthritis were
randomized into one of two groups (laser or
placebo) by an investigator not involved in
assessment, diagnosis or treatment.
Randomization was performed by using sealed,
randomly filled envelopes describing the treat-
ment group. Patients and the physiotherapist
responsible for the evaluation were unaware of
randomization results.
Sample size
Sample size was calculated assuming 80% power
to detect a 20% improvement in pain (VAS),
with a standard deviation of 2 points and a sig-
nificance level of 5%. The required sample
would be 17 patients per group.
Assessment
All participants were evaluated by the same
blinded physiotherapist at three different mea-
surement intervals: baseline (T1), following the
end of laser therapy after three weeks (T2) and
the end of exercise therapy after 11 weeks (T3).
The physiotherapist was trained to evaluate the
same way all patients at all times.
.Pain was assessed using a visual analogue
scale (VAS)
14
consisting of a 10 cm rule (with-
out numbers). At the left side, ‘no pain’ is
written, while on the right side, ‘unbearable
pain’. Patients were instructed to mark on the
rule what their level of pain was.
.Functionality was measured using the
Lequesne questionnaire,
15
which consists of
11 questions about pain, discomfort and
function. Scores range from 0 to 24 (from
‘no’ to ‘extremely severe’ dysfunction).
.Range of motion for flexion of the knees were
measured with the universal goniometer
(AESCULAP), according to the methods
described by Marques.
16
.Muscular strength was estimated at maximal
isometric force for the quadriceps, using a
portable dynamometer (Lafayette, USA).
Under stabilized conditions, patients, sitting
with knees flexed at 60(measured by a goni-
ometer),
17
were asked to extend the legs as far
Alfredo et al. 525
as they could. Three trials were conducted
and the mean value was obtained.
.Activity was measured using the Western
Ontario and McMaster Universities
Osteoarthritis (WOMAC) questionnaire,
18
which is self-administered and measures
pain, frozen joints and physical activity.
Increased scores suggest decreased activity.
In this study the most affected knee joint of
each participant was included.
Intervention
All patients were treated by the same physio-
therapist who had not taken part in the
evaluations.
Participants in the laser group received low
level laser therapy while the placebo group
received placebo therapy three times a week
for three weeks following initial assessment.
Both groups exercised three times a week for
the remaining eight weeks of the programme.
In the laser group, energy was irradiated over
the joint line onto five points of the synovial
region of the medial side of the knee and in
four points at the lateral side, at 3 J per point.
Total dose per knee was 27 J per treatment and
used previously calibrated equipment (Irradia
Class 3B; Stockholm, Sweden). In the placebo
group, procedures were identical but without
emission of energy.
The laser equipment had two identical pens,
one for the active treatment and one for the pla-
cebo treatment (sealed). The pen’s semi-conduc-
tor consisted of gallium arsenide with wave
length of 904 nm, frequency of 700 Hz, average
power of 60 mW, peak power of 20 W, pulse
duration 4.3 ms, 50 seconds per point (area 0.5
cm
2
). The parameters followed the recommen-
dation of the World Association of Laser
Therapy (WALT)
19
for osteoarthritis.
Exercises
All patients followed the same training pro-
gramme (Table 1). The intervention was divided
into three phases: P-1, P-2 and P-3 during eight
weeks with three sessions a week. Each session
lasted 45 minutes:
.10 minutes warming-up (treadmill, ergometer
bike or rowing machine);
.30 minutes 2–3 sets with P-1, P-2 or P-3;
.5 minutes stretching (hamstrings, quadriceps,
adductors, and gastrocmenius).
Statistical analysis
Data normality was assessed using the Shapiro–
Wilk test; homogeneity of data was estimated
using the Levene’s test. For the intergroup anal-
ysis the values were standardized as follows: For
variables where reduction meant improvement
(pain, function, WOMAC), we used the for-
mula: (T1–T2) 7AV1 and (T1–T3) 7AV1.
For variables where increase meant improve-
ment (range of motion and muscle strength),
we used the formula: (T1–T2) 7AV1 and
(T1–T3) 7AV1. To compare the two groups,
laser and placebo, we calculate the difference of
their means. Negative values mean that laser is
better than placebo and positive values mean
that placebo is better. Analyses between groups
were performed using the independent t-test for
the conditions T1 T2 and T1 T3. For
intragroup analysis, evaluation times were com-
pared by repeated-measures ANOVA (single
effect), followed by the Tukey post-test.
Analyses were conducted using the Statistical
Package for Social Sciences (SPSS version 17;
SPSS Inc., Chicago, IL, USA). An alpha level
of 0.05 was set for all comparisons.
Results
Sixty-one subject were eligible to take part in
study and 15 were excluded. Forty-six patients
were assessed at baseline and randomly allo-
cated in two different groups (laser group ¼24
and placebo group ¼22). Forty patients com-
pleted the treatment and attended the last assess-
ment (Figure 1).
526 Clinical Rehabilitation 26(6)
Table 2 displays the demographics of partic-
ipants in each group. There were no statistically
significant differences (P>0.05) for age, weight,
height, body mass index, gender and osteoar-
thritis degree between the two groups.
Table 3 shows that there was no significant
difference in any of the variables of both groups
at the time of the baseline (P>0.05).
The intergroup analysis showed that the laser
group presented significant improvement in the
variables of WOMAC, as pain (P¼0.033), func-
tion (P¼0.002) and total score (P¼0.008) at T2
compared to T1 and pain (P¼0.001), function
(0.002) and total score (0.003) in T3 compared
to T1. No other statistically significant differ-
ences were found in the other variables
(P>0.05) (Table 4).
Table 5 shows the intragroup analysis at the
different measurement intervals. The laser group
had significant improvement in pain scores
(P<0.05) and activity (P<0.001) between T1
and T2 and between T2 and T3 (P¼0.001) as
well as range of motion (P¼0.01) and function-
ality (P¼0.001) between T2 and T3. In the pla-
cebo group, no significant improvements were
seen for any of the variables (P>0.05).
Table 1. Exercise programme conducted over the eight weeks of treatment
Phases Exercises
P1 Each exercise had 30 repetitions and 2 sets:
(week 1–week 2) Sitting in the chair with a weight on the ankle, knee and stretch the
foot to rotate alternately in and out then change legs
Objectives:
Range of Motion
Lying prone. Bend the knee slowly as much as possible. Stretch
the knee slowly
Standing with support. Bend the knees to approximately 60
degrees. Push up again
Walk on a 3 m line without stepping off the line
Motor Learning
Balance Coordination
Walk–standing. Transfer your body weight from one leg to the
other
P2 Each exercise had 20 repetitions and 3 sets:
(week 3–week 5)
Objective:
Standing. Bend your knees to approximately 60 degrees, and
up again
Walk sidewards by crossing legs. To right and left
Strengthening Standing on a balance board. Hold the balance
Lying prone. Bend one knee as much as possible
One foot-standing on a step. Bend your knee until the other foot
touches the floor, push up again
P3 Each exercise had 20 repetitions and 3 sets:
(week 6–week 8) Walk sideward by crossing steps. To right and left
Objective:
Strengthening
Standing on one leg. Bend the knee to approximately 60 degrees,
and up again
Standing on a balance board. Keep the balance. More difficult if
eyes are closed
Standing on the floor. Get up on your toes, hold 1–2 seconds, and
get down again
Sitting with weight around the ankle. Stretch the knee slowly, hold
the stretch 3–4 seconds, and slowly down again
Alfredo et al. 527
Assessed for eligibility (n=61)
Excluded (n=15)
n=9)
n=6)
Analysis
Analysed (n=40)
Assessed after active LPL (n=24) Assessed after placebo LPL (n=22)
Randomized and registered (n=46)
Placebo group
Receive allocated to intervention (n= 22)
Placebo LPL 3 days a week, in 3 weeks
Laser group
Receive allocated to intervention (n=24)
Active LPL 3 days a week, in 3 weeks
Exercises 3 days a week, in 8 weeks
Assessed after exercise (n=20)
Discontinued
intervention (n=4)
Discontinued
intervention (n=2)
Assessed after exercise (n=20)
Baseline assessment (n=46)
Figure 1. Participant flow diagram.
528 Clinical Rehabilitation 26(6)
Discussion
The effects of low level laser, in combination
with a programme of exercises in patients with
knee osteoarthritis was assessed in this study.
Positive results were found in low level laser
therapy when associated with exercises in yield-
ing pain relief, improvement function and activ-
ity compared to the placebo group.
We postulate that analgesia in the laser group
after laser therapy may have been a consequence
of the anti-inflammatory properties of the low
level laser at 3 J, applied onto specific points,
suggested by WALT,
19
on the articular capsule.
Similar results were found by Bjordal et al.,
20
including the pain relief and improvement in
global health status of knee osteoarthritis
patients. In a meta-analysis, Brosseau et al.
6
sug-
gested that the significant pain relief associated
with low level laser may have been due to
increase in neurotransmitter levels, including
serotonin, which is important in endogenous
Table 2. Clinical and demographic characteristics of the participants in both groups
Characteristics
Laser group (n¼20)
Mean (SD)/n (%)
Placebo group (n¼20)
Mean (SD)/n (%) P-value
Age (years) 61.15 (7.52) 62.25 (6.87) 0.63
Weight (kg) 76.27 (10.32) 74.9 (15.73) 0.74
Height (m) 1.59 (0.08) 1.59 (0.09) 0.94
BMI (kg/m
2
) 30.16 (4.12) 29.21 (4.95) 0.51
Gender
Female 15 (75%) 16 (80%) 0.71
Male 5 (25%) 4 (20%) 0.71
Osteoarthritis degree
2 4 (20%) 9 (45%) 0.09
3 9 (45%) 4 (20%) 0.09
4 7 (35%) 7 (35%) 1.00
SD, standard deviation; BMI, body mass index.
Table 3. T-test among the variables pain, functionality, range of motion, muscle strength and activity at the time of
the baseline
Laser group (n¼20) Placebo group (n¼20)
Variables Mean (SD) Mean (SD) P-value
Pain (cm) 5.32 (3.55) 3.54 (3.06) 0.098
Functionality 11.88 (3.98) 11.55 (3.18) 0.776
Range of motion (degrees) 91.50 (13.79) 91.80 (20.42) 0.992
Muscle strength (H/kg) 11.63 (4.87) 9.96 (3.58) 0.207
Activity-WOMAC
Pain subscale 9.10 (4.92) 7.30 (3.54) 0.192
Stiffness subscale 3.05 (1.96) 2.95 (2.14) 0.878
Function subscale 33.85 (16.93) 27.15 (11.32) 0.188
Total score 46.05 (22.99) 38.00 (14.91) 0.196
SD, standard deviation; P-value for t-test; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.
Alfredo et al. 529
pain modulation. Hegedus et al.
21
and Montes-
Molina et al.
22
carried out clinical trials accord-
ing to the recommendations of WALT, using
830 nm laser with average power of 50 and 100
mW, respectively, with a dose of 6.0 J/point.
Effective results were recorded in pain relief
and improvements in microcirculation in the
irradiated area in patients with osteoarthritis
knee.
There is strong evidence that exercise reduces
pain and improves function in patients with
osteoarthritis,
23,24
and this may explain the
maintained benefits even after laser therapy
was discontinued. Our findings suggest that
analgesia induced by low level laser resulted in
improved exercise performance and this combi-
nation resulted in prolonged analgesic effects.
We also demonstrated the functional
improvement in the laser group in relation to
placebo. Similar results were found by Stelian
et al.,
25
who observed significant functional
improvement and pain reduction in the laser
group but not in placebo group in patients
with osteoarthritis. However, Brosseau et al.
26
found no significant improvement in pain reduc-
tion and functional status for hand osteoarthri-
tis patients for laser therapy versus placebo.
These results may be because the laser was
Table 4. Comparison between the groups for the variables pain, functionality, range of motion, muscle strength and
activity. Negative value suggests laser is better than placebo group
Laser group placebo group P-value
Variables Mean change score (95% CI) (intergroup)
Pain
T1 T2 0.43 (0.04) 0.071
T1 T3 0.31 (0.08) 0.120
Functionality
T1 T2 0.08 (0.22) 0.602
T1 T3 0.27 (0.04) 0.087
Range of motion (degree)
T1 T2 0.04 (0.16) 0.404
T1 T3 0.02 (0.08) 0.632
Muscle strength (H/kg)
T1 T2 0.07 (0.25) 0.395
T1 T3 0.12 (0.09) 0.266
Activity – WOMAC
Pain subscale
T1 T2 0.29 (0.02) 0.033*
T1 T3 0.33 (0.15) 0.001*
Stiffness subscale
T1 T2 0.24 (0.11) 0.173
T1 T3 0.31 (0.17) 0.202
Function subscale
T1 T2 0.35 (0.14) 0.002*
T1 T3 0.34 (0.13) 0.002*
Total score
T1 T2 0.30 (0.08) 0.008*
T1 T3 0.31 (0.12) 0.003*
95% CI, 95% confidence interval; P-value for t-test; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.
530 Clinical Rehabilitation 26(6)
applied on painful osteoarthritis-affected finger
joints (chronic stage) as well as three superficial
nerves innervating the painful area and not in
specific regions of the joint capsule.
In our study, parameters associated with
activity also improved in the laser group, cor-
roborating the findings of Gur et al.
27
in a sim-
ilarly conducted study (low level laser and
exercises also improved pain, functionality and
activity of patients with osteoarthritis).
Tascioglu et al.
28
however, did not find signifi-
cant improvement in the activity assessed by
WOMAC of patients receiving laser with a
wavelength 830 nm, 50 mW of mean power,
with doses ranging from 1.5 to 3 J. They believe
that this fact may be related to the laser modal-
ity, dosages and wavelength selection used.
In patients with knee osteoarthritis, quadri-
ceps strength is decreased by 50–60%, mainly
because of atrophy and arthrogenic inhibition.
29
It has been suggested that sensorimotor dysfunc-
tion of the quadriceps may be relevant to oste-
oarthritis progression
30,31
as a risk factor for
disability. We did not demonstrate improve-
ments in quadriceps muscle strength, however
functionality improved in the laser group follow-
ing the exercise therapy. We believe these results
are due to the fact that the exercise programme
was focused not only on quadriceps muscle
strength gain, but on the overall strengthening
of the lower limb. Montes-Molina et al.
22
used
830 nm laser at a dose of 6.0 J per point and
concluded that low level laser associated with
quadriceps exercise was effective in reducing
pain, a conclusion supported by our study.
Similar results were found by Hurley and
Scott,
32
who suggested that the improvement
of strength and functionality in knee
Table 5. Within-group difference in change score (T1, T2 and T3) for laser and placebo groups
Groups T1 T2 T3
Variables (n¼20/group) Mean (SD) Mean (SD) Mean (SD) P-value
Pain (cm) Laser 5.32 (3.55)
a
3.36 (3.47)
b
2.58 (3.27)
b
0.001*
Placebo 3.54 (3.06) 3.15 (2.94) 2.30 (2.25) 0.230
Functionality Laser 11.88 (3.98)
a
10.78 (4.62)
a
8.37 (4.27)
b
0.001*
Placebo 11.55 (3.18) 10.68 (3.08) 10.40 (3.91) 0.400
Range of motion (degree) Laser 91.50 (13.79)
a
91.40 (12.11)
a
99.45 (12.89)
b
0.010*
Placebo 91.80 (20.42) 95.65 (17.25) 96.55 (15.28) 0.180
Muscle strength (H/kg) Laser 11.63 (4.87) 11.8 (4.86) 12.52 (4.50) 0.700
Placebo 9.96 (3.58) 11.51 (6.62) 9.68 (3.65) 0.230
Activity – WOMAC
Pain subscale Laser 9.10 (4.92)
a
6.55 (3.32)
b
4.80 (4.36)
b
0.000*
Placebo 7.30 (3.54) 6.55 (3.98) 6.35 (3.48) 0.370
Stiffness subscale Laser 3.05 (1.96) 2.35 (2.30) 2.35 (2.21) 0.720
Placebo 2.95 (2.14) 2.65 (2.23) 2.6 (2.11) 0.200
Function subscale Laser 33.85 (16.93)
a
24.15 (13.58)
b
19.50 (14.04)
b
0.000*
Placebo 27.15 (11.32) 27.40 (13.88) 23.35 (12.18) 0.190
Total score Laser 46.05 (22.99)
a
33.05 (18.62)
b
26.65 (20.17)
b
0.000*
Placebo 38.00 (14.91) 36.60 (18.34) 32.30 (16.82) 0.22
*P-value for ANOVA.
a,b
Identify which values are statistically different between after multiple comparison test.
WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.
Alfredo et al. 531
osteoarthritis was so substantial that it could
postpone or totally avoid surgical interventions.
Although no significant difference was
observed between groups for range of motion,
in intra-group analysis improvement in the laser
group after exercise was observed.
Corroborating our findings, Gur et al.
27
also
found statistical significant improvement in the
flexion of the knee in all groups treated with
laser except the placebo group. However,
Bulow et al.
9
failed to demonstrate significant
improvement in pain and range of motion
when comparing laser and placebo. However,
they used very low doses of laser (less than 3 J)
over pain points, and not necessarily over the
soft periarticular tissues.
Our findings suggest that low level laser ther-
apy when associated with exercises is effective in
yielding pain relief, function and activity in
patients with knee osteoarthritis.
The major study limitations were the small
number of patients, the absence of a control
group, which would allow us to assess the natural
course of the disease, and the absence of follow-
up. Future studies should increase the number of
patients, include a control group, add a group
which receives low level laser therapy and exercise
simultaneously from the very beginning and a
long-term follow-up assessment.
Clinical messages
.The application of low level laser three
times per week for three weeks can assist
in the execution of exercises in patients
with knee osteoarthritis.
.The combination of laser and exercise can
improve pain, function and activities in
subject with knee osteoarthritis.
Disclosure statement
No competing financial interests exist.
Clinical trials
[Low power laser and exercise in osteoarthritis of the
knee: a randomized clinical trial, CT01306435.]
Conflict of interest
There is no conflict of interest.
Funding
This study was supported financially by: Fundac¸ a
˜ode
Amparo a
`Pesquisa do Estado de Sa
˜o Paulo
(FAPESP) – Foundation of Research Support of
Sa
˜o Paulo State and Coordenac¸ a
˜ode
Aperfeic¸ oamento de Pessoal de Nı
´vel Superior
(CAPES) – Coordination for the Improvement of
Higher Level – or Education – Personnel.
Biostatistics Support Group, Department of
Dentistic, School of Odontology, University of Sa
˜o
Paulo, Sa
˜o Paulo, Brazil.
References
1. Jordan KM, Arden NK, Bannwarth B, et al. EULAR
Recommendations 2003: an evidence based approach to
the management of knee osteoarthritis: report of a task
force of the standing committee for international clinical
studies including therapeutic trials (ESCISIT). Ann
Rheum Dis 2003; 62: 1145–1155.
2. Felson DT, Lawrence RC, Hochberg MC, et al.
Osteoarthritis: new insights. Part 2: treatment
approaches. Ann Intern Med 2000; 133: 726–737.
3. Chachade WH, Giorgi RDN and Pastor EMH.
Osteoartrite. Rev Bras Med 2001; 58: 304–314.
4. Jamtvedt G, Dahm KT, Christie A, et al. Physical ther-
apy interventions for patients with osteoarthritis of the
knee: an overview of systematic reviews. Phys Ther 2008;
88: 123–136.
5. Herman J and Khosla RC. In vitro effect of Nd: YAG
laser radiation on cartilage metabolism. J Rheumatol
1988; 15: 1818–1826.
6. Brosseau L, Welch V, Wells G, et al. Low level laser
therapy for osteoarthritis and rheumatoid arthritis: a
metaanalysis. J Rheumatol 2000; 27: 1961–1969.
7. Walker J. Relief from chronic pain by low power laser
therapy in the early stages of rheumatoid arthritis onset.
Laser Ther 1999; 11: 79–87.
8. Bjordal JM, Johnson MI, Lopes-Martins RA, Bogen B,
Chow R and Ljunggren AE. Short-term efficacy of
physical interventions in osteoarthritic knee pain: A sys-
tematic review and meta-analysis of randomized pla-
cebo-controlled trials. BMC Musculoskelet Disord
2007; 8: 1–14.
9. Bu
¨low PM, Jensen H and Danneskiold-Samsøe B.
Lower power Ga-Al-As laser treatment of painful oste-
oarthritis of the knee. A double-blind placebo controlled
study. Scand J Rehabil Med 1994; 26: 155–159.
10. Pisters MF, Veenhof C, van Meeteren NL, et al. Long-
term effectiveness of exercise therapy in patients with
532 Clinical Rehabilitation 26(6)
osteoarthritis of the hip or knee: a systematic review.
Arthritis Rheum 2007; 57: 1245–1253.
11. Veenhof C, Koke AJA, Dekker J, et al. Effectiveness of
behavioral graded activity in patients with osteoarthritis
of the hip and/or knee: a randomized clinical trial.
Arthritis Care Res 2006; 55: 925–934.
12. Kellgren JH and Lawrence JS. Radiological assessment
of rheumatoid arthritis. Ann Rheum Dis 1957; 16:
485–493.
13. Altman R, Asch E, Bloch D, et al. Development of cri-
teria for the classification and reporting of osteoarthri-
tis. Classification of osteoarthritis of the knee.
Diagnostic and Therapeutic Criteria Committee of the
American Rheumatism Association. Arthritis Rheum
1986; 29: 1039–1049.
14. Revill SI, Robinson JO, Rosen M and Hogg MI. The
reliability of a linear analogue for evaluating pain.
Anaesthesia 1976; 31: 1191–1198.
15. Lequesne MG. The algofunctional indices for hip and
knee osteoarthritis. J Rheumatol 1997; 24: 779–781.
16. Marques AP. Manual de goniometria, second edition.
Editora Manole, 2003.
17. Piva SR, Goodnite EA and Childs JD. Strength around
the hip and flexibility of soft tissues in individuals with
and without patellofemoral pain syndrome. J Orthop
Sports Phys Ther 2005; 35: 793–801.
18. Bellamy N, Buchanan WW, Goldsmith CH, Campbell J
and Stitt LW. Validation study of WOMAC: a health
status instrument for measuring clinically important
patient relevant outcomes to antirheumatic drug therapy
in patients with osteoarthritis of the hip or knee. J
Rheumatol 1988; 15: 1833–1840.
19. World Association of Laser Therapy (WALT).
Consensus agreement on the design and conduct of clin-
ical studies with low-level laser therapy and light therapy
for musculoskeletal pain and disorders. Photomed Laser
Surg 2006; 24: 761–762.
20. Bjordal JM, Couppe
´C, Chow RT, Tuner J and
Ljunggren EA. A systematic review of low level laser
therapy with location-specific doses for pain from
chronic joint disorders. Aust J Physiother 2003; 49:
107–116.
21. Hegedus B, Viharos L, Gervain M and Ga
´lfi M. The
effect of low-level laser in knee osteoarthritis: a
double-blind, randomized, placebo-controlled trial.
Photomed Laser Surg 2009; 27: 577–584.
22. Montes-Molina R, Madronero-Agreda MA, Romojaro-
Rodriguez AB, et al. Efficacy of interferential low-level
laser therapy using two independent sources in the treat-
ment of knee pain. Photomed Laser Surg 2009; 27:
467–471.
23. American College of Rheumatology Subcommittee on
Osteoarthritis Guidelines. Recommendations for the
medical management of osteoarthritis of the hip and
knee. Arthritis Rheum 2000; 43: 1905–1915.
24. Carvalho NAA, Bittar St, Pinto FRS, Ferreira M and
Sitta RR. Manual for guided home exercises for osteo-
arthritis of the knee. Clinics 2010; 65: 775–780.
25. Stelian J, Gil I, Habot B, et al. Improvement of pain and
disability in elderly patients with degenerative osteoar-
thritis of the knee treated with narrow-band light ther-
apy. J Am Geriatr Soc 1992; 40: 23–26.
26. Brosseau L, Wells G, Marchand S, et al. Randomized
controlled trial on low level laser therapy (LLLT) in the
treatment of osteoarthritis (OA) of the hand. Lasers
Surg Med 2005; 36: 210–219.
27. Gur A, Cosut A, Sarac AJ, Cevik R, Nas K and Uyar A.
Efficacy of different therapy regimes of low-power laser
in painful osteoarthritis of the knee: a double-blind and
randomized-controlled trial. Lasers Surg Med 2003; 33:
330–338.
28. Tascioglu F, Armagan O, Tabak Y, Corapci I and Oner
C. Low power laser treatment in patients with knee oste-
oarthritis. Swiss Med Wkly 2004; 134: 254–258.
29. Hassan B, Mockett S and Doherty M. Static postural
sway, proprioception, and maximal voluntary quadri-
ceps contraction in patient with knee osteoarthritis and
normal control participants. Ann Rheum Dis 2001; 60:
612–618.
30. Slemenda C, Brandt KD, Heilman DK, et al.
Quadriceps weakness and osteoarthritis of the knee.
Ann Intern Med 1997; 127: 97–104.
31. Hurley M, Scott D, Rees J and Newham D.
Sensorimotor changes and functional performance in
patients with knee osteoarthritis. Ann Rheum Dis 1997;
56: 641–648.
32. Hurley MV and Scott DL. Improvements in quadriceps
sensorimotor function and disability patients with knee
osteoarthritis following a clinically practicable exercise
regime. Br J Rheumatol 1998; 37: 1181–1187.
Alfredo et al. 533
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