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Chronic Knee PainPhase 2/3NCT05816798

Photobiomodulation in Chronic Knee Pain in Patients Who Are in PreRehabilitation for Bariatric Surgery

A Phase 2/3 study testing Photobiomodulation and Standard Physiotherapy Tretament in people with Chronic Knee Pain and Obesity, Morbid, run by University of Nove de Julho at 1 site in Brazil.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
Search all trials

Trial summary

Chronic pain is a global public health problem, which intensifies even more in the obese population, reaching about 33% of these patients. Among the topography, chronic knee pain affects 80%, constituting an important cause of disability and decreased quality of life. Read more about this study

Who is it for?
Ages 18 to 70 years
Conditions the study is for
Chronic Knee Pain, Obesity, Morbid
What is being tested?
Photobiomodulation and Standard Physiotherapy Tretament
Type of treatment
Medical device
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
62 participants
Where
1 siteBrazil
Study dates
28 Jul 2023to Feb 2026
Phase
Phase 2/3
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 70 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Obese patients with indication for bariatric surgery performed in routine follow-up at the Gastric Surgery Outpatient Clinic of HC-UFG;
  • Patients with chronic pain (> 3 months) in the knees bilaterally. Patients will be asked in the initial evaluation if they feel pain located in the topography of the knees that has been compromising their functionality both in daily activities and at work, and that lasts for more than or equal to 3 months. This pain may be reported as continuous or intermittent;
  • Sign the Informed Consent Term approved by the HC-UFG Ethics Committee.

Who cannot join

  • - Loss of follow-up in the outpatient clinic of origin and in the Physiotherapy sector, even though the use of laser therapy was maintained according to the study protocol;
  • Any reported adverse effects from the use of FBM reported;
  • Patients in whom there are changes in the medications being used for chronic pain during the study protocol will be excluded from this study. Minimal changes in the dosages of medications already in use can be tolerated, as long as there are no changes in the type of medication, but only in the prescribed dose. These modifications throughout the study, if they occur, will be described.
  • Death
  • Withdrawal of the informed consent by the participant
  • If the patient, for any reason, is excluded from the indication of bariatric surgery
Show all 21Show fewer
  • Emergence during the study of any of the non-inclusion criteria, like: .
  • Patients with other rheumatologic diseases and/or systemic inflammatory diseases (rheumatoid arthritis, Reiter's arthritis, ankylosing spondylitis, generalized polyarthritis) or previous musculoskeletal diseases in the knees;
  • Clinical manifestations or complaints of knee arthralgia related to diseases other than obesity.
  • Previous use in the last 90 days of treatment with the use of Phototherapy for the same or another indication;
  • Clinical signs of neuropathy, including radiculopathies and peripheral nerve injuries;
  • Pain in the lower limb, originating from the lumbar spine (lombosciatalgia)
  • Use of corticosteroids at an immunosuppressive dose (20mg daily of prednisone or equivalent for at least 14 days);
  • Infection or tumor at the site of therapy application;
  • Current chronic infections such as tuberculosis or chronic hepatitis treated or not.
  • Blood clotting disorders (including thrombosis) at the application site.
  • Diagnosis of fibromyalgia;
  • Serious psychiatric disorders that require psychiatric care;
  • Systemic injections and/or joint injections of corticosteroids or hyaluronic acid during the last 48 hours prior to the initial assessment of the study;
  • Psychoaffective disorder that compromises adherence to treatment;
  • Any history of sensitivity to light or phototherapies.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Rebeca B Cecatto, MD PHD contact

+5511970842496

rebeca.boltes@uni9.pro.br

Brazil1 site, 1 recruiting

  • Gastric Outpatient Clinic of HC-UFG

    Goiânia, Goiás, 74605-050

    Ana Cristina Amorim, M.D., anafisiatra@gmail.com

    Recruiting

Other trials in Brazil

About this study

Official title: Photobiomodulation in Chronic Knee Pain in Patients Who Are in PreRehabilitation for Bariatric Surgery: Double Blind, Randomized, Controlled Placebo Clinical Trial

Chronic pain is a global public health problem, which intensifies even more in the obese population, reaching about 33% of these patients. Among the topography, chronic knee pain affects 80%, constituting an important cause of disability and decreased quality of life. In addition, in grade 3 obesity, also called morbid obesity, in which bariatric surgery is already indicated, knee pain makes it difficult or prevents participation in the pre-habilitation program that includes physical therapy through therapeutic exercises with the aim of reducing postoperative complications. In this sense, a double-blind, randomized, placebo-controlled clinical trial will be conducted with the objective of evaluating the effect of photobiomodulation (PBM) on pain and functionality of obese patients with chronic knee pain who are in a prehabilitation program for bariatric surgery, discussing its role as an analgesic therapy and modifier of peripheral and central sensitization mechanisms of the pain pathway. PBM is a safe treatment option, with no undesirable effects and low cost. The primary outcomes will be pain intensity, through visual analogue scale, and Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, validated version for Portuguese - Brazil. Secondary outcomes will be pressure pain threshold and rolling pinch maneuver measured by digital algometer. Other exploratory outcomes will be 6-minute walk test, knee range of motion, SF-36 quality of life questionnaire. There will be 2 groups: an intervention group (photobiomodulation associated with standard physiotherapy treatment) and another placebo group (device turned off associated with the same standard physiotherapy treatment). The application sites will be knees and lumbar paravertebral 2 times a week for 12 weeks. The dosimetric standards will be 4J/point in the knees and 3J/point in the lumbar. The results obtained will be statistically analyzed and later published in a scientific journal.

Read the detailed description

Chronic pain is a global public health problem, which intensifies even more in the obese population, reaching about 33% of these patients. Among the topography, chronic knee pain affects 80%, constituting an important cause of disability and decreased quality of life. In addition, in grade 3 obesity, also called morbid obesity, in which bariatric surgery is already indicated, knee pain makes it difficult or prevents participation in the pre-habilitation program that includes physical therapy through therapeutic exercises with the aim of reducing postoperative complications. In this sense, a double-blind, randomized, placebo-controlled clinical trial will be conducted with the objective of evaluating the effect of photobiomodulation (PBM) on pain and functionality of obese patients with chronic knee pain who are in a prehabilitation program for bariatric surgery, discussing its role as an analgesic therapy and modifier of peripheral and central sensitization mechanisms of the pain pathway. PBM is a safe treatment option, with no undesirable effects and low cost. The primary outcomes will be pain intensity, through visual analogue scale, and Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, validated version for Portuguese - Brazil. Secondary outcomes will be pressure pain threshold and rolling pinch maneuver measured by digital algometer. Other exploratory outcomes will be 6-minute walk test, knee range of motion, SF-36 quality of life questionnaire. There will be 2 groups: an intervention group (photobiomodulation using Therapy EC-DMC device associated with standard physiotherapy treatment) and another placebo group (device turned off associated with the same standard physiotherapy treatment). The application sites will be knees (4 anatomically described points) and lumbar paravertebral (levels L3 to S2 bilateral - 10 points, being 05 points each side) 2 times a week for 12 weeks. The dosimetric standards will be 4J/point (40 seconds) in the knees and 3J/point (30 seconds) in the lumbar. The results obtained will be statistically analyzed using SPSS 28.0 software, and later published in a scientific journal.

Being tested
Photobiomodulation, Standard Physiotherapy Tretament, Photobiomodulation Placebo
Keywords
Photobiomodulation, Chronic knee pain, Obesity Morbid, Central and periferic sensitivity, Nociception
Medical subject headings
Obesity, Morbid

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • PhotobiomodulationDevice

    Also called Low level laser therapy

    PBM is a therapeutic technique that uses light at different wavelengths (red or infrared), in a non-invasive way in which non-ionizing irradiation is used to produce a series of photophysical and photochemical effects when applied to biological tissues (humans and animals). Regarding the clinical results, numerous articles have already demonstrated the effect of PBM in improving pain and disability in patients with knee joint pain.

  • Standard Physiotherapy TretamentOther

    standard treatment (physiotherapy-standard exercises: Cardiopulmonary physiotherapy and Physiotherapy with global muscle strengthening exercises). This program will be maintained for all study patients, for both groups, throughout the data collection period and includes activities 2X per week.)

  • Photobiomodulation PlaceboDevice

    The same interventions described of Photobiomodulation Group bu device will be turned off

Study groups in NCT05816798
Study groupRoleWhat they receive
Photobiomodulation InterventionExperimentalPBM therapy sessions will be performed with the Therapy EC device (DMC brand) 100mW power, which is a Low Intensity Laser Therapy. During the interventions, the patient will be allowed to choose the position that is most comfortable for him and accompanied by the physical therapist throughout the procedure. Examiner and patient will be wearing protective eyewear. Applications will occur after local asepsis of the device and skin. Patients will receive the PBM therapy described below: * Paravertebral region at levels L3 to S2:1 cm lateral to the corresponding level, on each right and left side, which are root levels that innervate the knee joint (totaling 10 paravertebral points) with 3 Joules per point (30 s) in each point * Knees bilaterally (4 points each knee): anteromedial portal; anterolateral portal; apex of patella; base of patella; with 4 J per point (40 s)
Receives: Device: Photobiomodulation; Other: Standard Physiotherapy Tretament
Photobiomodulation PlaceboPlacebo comparatorControl group research participants will receive the standard treatment described as well as placebo PBM treatment to mask the treatment. The number of points, dose and PBM application site will be the same as described in the PBM Intervention Group item, however the PBM equipment will be turned off.
Receives: Other: Standard Physiotherapy Tretament; Device: Photobiomodulation Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Visual Analog Scale Change

    10 cm ruler with Visual Analog Pain Scale where 0 indicates no pain and 10 indicates maximum pain possible

    Measured: At the initial assessment (baseline in the same day of first PBM therapy) and at the end of the intervention (after 14 weeks from baseline)

  2. Knee injury and Osteoarthritis Outcome Score (KOOS) Change

    A specific scale for patients with knee pain

    Measured: At the initial assessment (baseline in the same day of first PBM therapy) and at the end of the intervention (after 14 weeks from baseline)

Secondary outcomes (2)

  1. The dermatomes pinching and rolling maneuver Change

    The pinching and rolling maneuver in the L1, L2, L3, L4, L5, S1 and S2 dermatomes will also be performed to assess signs of subcutaneous hyperalgesia and the pain threshold will be measured with an algometer.

    Measured: At the initial assessment (baseline in the same day of first PBM therapy) and at the end of the intervention (after 14 weeks from baseline)

  2. Pressure pain thresholds will be assessed in the muscles related to knee Change

    Pressure pain thresholds will be evaluated with algometer in the muscles: vastus medialis, adductor longus, rectus femoris, vastus lateralis, tibialis anterior, peroneus longus, popliteus, sartorius, gracilis, quadratus lumborum, supraspinatus ligaments (Lumbar) between L1-L2, L2- L3, L3-L4, L4-L5 and L5-S1 and sacral (S) S1-S2, as previously described in the literature

    Measured: At the initial assessment (baseline in the same day of first PBM therapy) and at the end of the intervention (after 14 weeks from baseline)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Apr 2023
  2. Study start28 Jul 2023
  3. Primary completion1 May 2025
  4. Study completionFeb 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 2/3
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
62 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05816798
Sponsor's protocol ID
PhotobioKneepain
Status last verified
Jun 2025
First submitted
22 Mar 2023
Last updated
6 Jun 2025
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Yes: The plan of Data Manage are available in https://doi.org/10.48321/D1MW8J Rebeca Cecatto. (2023). "Photobiomodulation in Chronic Knee Pain in Patients Who Are in PreRehabilitation for Bariatric Surgery: Double Blind, Randomized, Controlled Placebo Clinical Trial " \[Data Management Plan\]. DMPTool. https://doi.org/10.48321/D1MW8J

Publications

  • Chen X, Tang H, Lin J, Zeng R. Causal relationships of obesity on musculoskeletal chronic pain: A two-sample Mendelian randomization study. Front Endocrinol (Lausanne). 2022 Aug 23;13:971997. doi: 10.3389/fendo.2022.971997. eCollection 2022.

    PubMed 36082069

  • Chin SH, Huang WL, Akter S, Binks M. Obesity and pain: a systematic review. Int J Obes (Lond). 2020 May;44(5):969-979. doi: 10.1038/s41366-019-0505-y. Epub 2019 Dec 17.

    PubMed 31848456

  • Imamura M, Imamura ST, Kaziyama HH, Targino RA, Hsing WT, de Souza LP, Cutait MM, Fregni F, Camanho GL. Impact of nervous system hyperalgesia on pain, disability, and quality of life in patients with knee osteoarthritis: a controlled analysis. Arthritis Rheum. 2008 Oct 15;59(10):1424-31. doi: 10.1002/art.24120.

    PubMed 18821657

  • Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophys. 2017;4(3):337-361. doi: 10.3934/biophy.2017.3.337. Epub 2017 May 19.

    PubMed 28748217

  • Dompe C, Moncrieff L, Matys J, Grzech-Lesniak K, Kocherova I, Bryja A, Bruska M, Dominiak M, Mozdziak P, Skiba THI, Shibli JA, Angelova Volponi A, Kempisty B, Dyszkiewicz-Konwinska M. Photobiomodulation-Underlying Mechanism and Clinical Applications. J Clin Med. 2020 Jun 3;9(6):1724. doi: 10.3390/jcm9061724.

    PubMed 32503238

  • Amorim ACFG, Belchior TCF, Silva Rodarte TND, Reboucas Junior FA, Rodrigues MFSD, Marcos RL, Lino-Dos-Santos-Franco A, Cecatto RB. Photobiomodulation therapy for chronic knee pain in obese patients in pre-rehabilitation for bariatric surgery: randomised, placebo-controlled, double-blinded, clinical trial protocol. BMJ Open. 2024 Jul 1;14(6):e079864. doi: 10.1136/bmjopen-2023-079864.

    PubMed 38951012

Questions about this trial

What is this clinical trial studying?

A Phase 2/3 study testing Photobiomodulation and Standard Physiotherapy Tretament in people with Chronic Knee Pain and Obesity, Morbid, run by University of Nove de Julho at 1 site in Brazil.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 21 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 6 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Brazil. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Rebeca B Cecatto, MD PHD (+5511970842496, rebeca.boltes@uni9.pro.br), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Visual Analog Scale Change (time frame: At the initial assessment (baseline in the same day of first PBM therapy) and at the end of the intervention (after 14 weeks from baseline)). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05816798, which also lists 6 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jun 2025.

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