Pain & Photobiomodulation Research

The below research articles on photobiomodulation, phototherapy or low level laser therapy are for information purposes only and the full articles can be found at PubMed.gov

Int J Radiat Biol. 2019 Sep;95(9):1326-1336. doi: 10.1080/09553002.2019.1625464. Epub 2019 Aug 7.

The effect of red-to-near-infrared (R/NIR) irradiation on inflammatory processes

Tomasz Walski¹², Krystyna Dąbrowska¹³, Anna Drohomirecka⁴, Natalia Jędruchniewicz¹, Natalia Trochanowska-Pauk¹², Wojciech Witkiewicz¹, Małgorzata Komorowska¹²

Abstract

Introduction: Near-infrared (NIR) and red-to-near-infrared (R/NIR) radiation are increasingly applied for therapeutic use. R/NIR-employing therapies aim to stimulate healing, prevent tissue necrosis, increase mitochondrial function, and improve blood flow and tissue oxygenation. The wide range of applications of this radiation raises questions concerning the effects of R/NIR on the immune system. Methods: In this review, we discuss the potential effects of exposure to R/NIR light on immune cells in the context of physical parameters of light. Discussion: The effects that R/NIR may induce in immune cells typically involve the production of reactive oxygen species (ROS), nitrogen oxide (NO), or interleukins. Production of ROS after exposure to R/NIR can either be inhibited or to some extent increased, which suggests that detailed conditions of experiments, such as the spectrum of radiation, irradiance, exposure time, determine the outcome of the treatment. However, a wide range of immune cell studies have demonstrated that exposure to R/NIR most often has an anti-inflammatory effect. Finally, photobiomodulation molecular mechanism with particular attention to the role of interfacial water structure changes for cell physiology and regulation of the inflammatory process was described. Conclusions: Optimization of light parameters allows R/NIR to act as an anti-inflammatory agent in a wide range of medical applications.

AIMS Biophys. 2017;4(3):337-361. doi: 10.3934/biophy.2017.3.337. Epub 2017 May 19.

Mechanisms and applications of the anti-inflammatory effects of photobiomodulation

Michael R Hamblin¹²³

Abstract

Photobiomodulation (PBM) also known as low-level level laser therapy is the use of red and near-infrared light to stimulate healing, relieve pain, and reduce inflammation. The primary chromophores have been identified as cytochrome c oxidase in mitochondria, and calcium ion channels (possibly mediated by light absorption by opsins). Secondary effects of photon absorption include increases in ATP, a brief burst of reactive oxygen species, an increase in nitric oxide, and modulation of calcium levels. Tertiary effects include activation of a wide range of transcription factors leading to improved cell survival, increased proliferation and migration, and new protein synthesis. There is a pronounced biphasic dose response whereby low levels of light have stimulating effects, while high levels of light have inhibitory effects. It has been found that PBM can produce ROS in normal cells, but when used in oxidatively stressed cells or in animal models of disease, ROS levels are lowered. PBM is able to up-regulate anti-oxidant defenses and reduce oxidative stress. It was shown that PBM can activate NF-kB in normal quiescent cells, however in activated inflammatory cells, inflammatory markers were decreased. One of the most reproducible effects of PBM is an overall reduction in inflammation, which is particularly important for disorders of the joints, traumatic injuries, lung disorders, and in the brain. PBM has been shown to reduce markers of M1 phenotype in activated macrophages. Many reports have shown reductions in reactive nitrogen species and prostaglandins in various animal models. PBM can reduce inflammation in the brain, abdominal fat, wounds, lungs, spinal cord.

Lasers Med Sci. 2020 Sep;35(7):1509-1518. doi: 10.1007/s10103-019-02941-y. Epub 2020 Feb 17.

Attenuation of the inflammatory response and polarization of macrophages by photobiomodulation

Kun Li¹, Zhuowen Liang¹, Jiawei Zhang¹, Xiaoshuang Zuo¹, Jiakai Sun¹, Qiao Zheng¹, Jiwei Song¹, Tan Ding¹, Xueyu Hu², Zhe Wang³

Abstract

In spinal cord injury (SCI), inflammation is a major mediator of damage and loss of function and is regulated primarily by the bone marrow-derived macrophages (BMDMs). Photobiomodulation (PBM) or low-level light stimulation is known to have anti-inflammatory effects and has previously been used in the treatment of SCI, although its precise cellular mechanisms remain unclear. In the present study, the effect of PBM at 810 nm on classically activated BMDMs was evaluated to investigate the mechanisms underlying its anti-inflammatory effects. BMDMs were cultured and irradiated (810 nm, 2 mW/cm²) following stimulation with lipopolysaccharide and interferon-γ. CCK-8 assay, 2',7'-dichlorofluorescein diacetate assay, and ELISA and western blot analysis were performed to measure cell viability, reactive oxygen species production, and inflammatory marker production, respectively. PBM irradiation of classically activated macrophages significantly increased the cell viability and inhibited reactive oxygen species generation. PBM suppressed the expression of a marker of classically activated macrophages, inducible nitric oxide synthase; decreased the mRNA expression and secretion of pro-inflammatory cytokines, tumor necrosis factor alpha, and interleukin-1 beta; and increased the secretion of monocyte chemotactic protein 1. Exposure to PBM likewise significantly reduced the expression and phosphorylation of NF-κB p65 in classically activated BMDMs. Taken together, these results suggest that PBM can successfully modulate inflammation and polarization in classically activated BMDMs. The present study provides a theoretical basis to support wider clinical application of PBM in the treatment of SCI.

Lasers Surg Med. 2020 Nov;52(9):890-896. doi: 10.1002/lsm.23240. Epub 2020 Mar 22.

Photobiomodulation Decreases Hyperalgesia in Complex Regional Pain Syndrome: An Experimental Mouse Model Subjected to Nicotine

Mariana Rodrigues¹, Ramon B Cardoso¹, Heloyse U Kuriki¹, Alexandre M Marcolino¹, Elaine Caldeira de Oliveira Guirro², Rafael I Barbosa¹

Abstract

Background and objectives: Complex regional pain syndrome (CRPS) is defined as an extreme and chronic pain condition, and photobiomodulation has relevance as a complementary treatment for CRPS. The objective of this study was to verify the effects of photobiomodulation (PBMT) therapy protocols at two wavelengths 660 and 830 nm, associated or not to nicotine in complex regional pain syndrome type I (CRPS-I).

Study design/materials and methods: Sixty-four Swiss mice were divided into the following groups: (i) Naive, (ii) Sham, (iii) Control, (iv) 660 nm, (v) 830 nm, (vii) Nicotine, (vii) Nicotine/660 nm, and (viii) Nicotine/830 nm. CRPS-I was induced in an experimental ischemia/reperfusion model by affixing an elastic ring, proximal to the ankle joint of the right hind mouse paw, for 3 hours. Nicotine, in the respective groups was administered for 28 days prior to the induction of CRPS-I. PBMT was applied immediately after the procedure and for 20 consecutive days. The animals were evaluated for mechanical hyperalgesia, thermal hyperalgesia, paw edema at baseline and for 7, 14, and 21 days. Statistical analyses comprised a mixed-effects model, using the Tukey post hoc test (P < 0.05).

Results: The PBMT wavelengths in 660 and 830 nm groups had beneficial effects (P < 0.05) in reducing mechanical and thermal hyperalgesia, but the effects at 660 nm were significantly better than 830 nm. At reducing edema, both wavelengths had significant effects statistically, absolutely no difference between them.

Conclusions: The use of PBMT (660 and 830 nm) was effective in reducing mechanical hyperalgesia and thermal hyperalgesia; however, PBMT at 660 nm generated significant results. In reducing edema, both wavelengths had similar effects, which were significant statistically. The deleterious effects of nicotine were evident statistically and were softened when treated with PBMT (P < 0.05).

Photobiomodul Photomed Laser Surg. 2019 Jan;37(1):4-16. doi: 10.1089/photob.2018.4512.

Therapeutic Efficacy of Home-Use Photobiomodulation Devices: A Systematic Literature Review

Lilach Gavish¹, Nicolette Nadene Houreld²

Abstract

Objective: Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications. Background: Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications. Methods: A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication. Results: Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results. Conclusions: Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications.

Altern Ther Health Med. 2018 Sep;24(5):8-10.

Review of Literature on Low-level Laser Therapy Benefits for Nonpharmacological Pain Control in Chronic Pain and Osteoarthritis

Robert Dima, Vinicius Tieppo Francio, Chris Towery, Saied Davan

Abstract

Introduction: Low-level laser therapy (LLLT) is a form of light therapy that triggers biochemical changes within cells. Photons are absorbed by cellular photoreceptors, triggering chemical alterations and potential biochemical benefits to the human body. LLLT has been used in pain management for years and is also known as cold laser therapy, which uses low-frequency continuous laser of typically 600 to 1000 nm wavelength for pain reduction and healing stimulation. Many studies have demonstrated analgesic and anti-inflammatory effects provided by photobiomodulation in both experimental and clinical trials.

Objective: The purpose of this research article was to present a summary of the possible pain management benefits of LLLT.

Results: In cold laser therapy, coherent light of wavelength 600 to 1000 nm is applied to an area of concern with hope for photo-stimulating the tissues in a way that promotes and accelerates healing. This is evidenced by the similarity in absorption spectra between oxidized cytochrome c oxidase and action spectra from biological responses to light. LLLT, using the properties of coherent light, has been seen to produce pain relief and fibroblastic regeneration in clinical trials and laboratory experiments. LLLT has also been seen to significantly reduce pain in the acute setting; it is proposed that LLLT is able to reduce pain by lowering the level of biochemical markers and oxidative stress, and the formation of edema and hemorrhage. Many studies have demonstrated analgesic and anti-inflammatory effects provided by photobiomodulation in both experimental and clinical trials.

Conclusion: Based on current research, the utilization of LLLT for pain management and osteoarthritic conditions may be a complementary strategy used in clinical practice to provide symptom management for patients suffering from osteoarthritis and chronic pain.

Lasers Med Sci. 2017 Jan;32(1):101-108. doi: 10.1007/s10103-016-2091-8. Epub 2016 Oct 10.

Effects of photobiomodulation therapy, pharmacological therapy, and physical exercise as single and/or combined treatment on the inflammatory response induced by experimental osteoarthritis

Shaiane Silva Tomazoni¹, Ernesto Cesar Pinto Leal-Junior², Rodney Capp Pallotta³, Simone Teixeira³, Patricia de Almeida³, Rodrigo Álvaro Brandão Lopes-Martins⁴

Abstract

Osteoarthritis (OA) triggers increased levels of inflammatory markers, including prostaglandin (PG) E₂ and proinflammatory cytokines. The elevation of cytokine levels is closely associated with increased articular tissue degeneration. Thus, the use of combination therapies may presumably be able to enhance the effects on the modulation of inflammatory markers. The present study aimed to evaluate and compare the effects of photobiomodulation therapy (PBMT), physical exercise, and topical nonsteroidal anti-inflammatory drug (NSAID) use on the inflammatory process after they were applied either alone or in different combinations. OA was induced by intra-articular papain injection in the knee of rats. After 21 days, the animals began treatment with a topical NSAID and/or with physical exercise and/or PBMT. Treatments were performed three times a week for eight consecutive weeks, totaling 24 therapy sessions. Analysis of real-time polymerase chain reaction (RT-PCR) gene expression; interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) protein expression; and PGE₂ levels by enzyme-linked immunosorbent assay (ELISA) was conducted. Our results showed that PBMT alone and Exerc + PBMT significantly reduced IL-1β gene expression (p < 0.05) while no treatment changed both IL-6 and TNF-α gene expression. Treatment with NSAID alone, PBMT alone, Exerc + PBMT, and NSAID + PBMT reduced IL-1β protein expression (p < 0.05). All therapies significantly reduced IL-6 and TNF-α protein expression (p < 0.05) compared with the OA group. Similarly, all therapies, except Exerc, reduced the levels of PGE₂ (p < 0.05) compared with the OA group. The results from the present study indicate that treatment with PBMT is more effective in modulating the inflammatory process underlying OA when compared with the other therapies tested.

J Biomed Opt. 2016 Oct 1;21(10):108001. doi: 10.1117/1.JBO.21.10.108001.

Isolated and combined effects of photobiomodulation therapy, topical nonsteroidal anti-inflammatory drugs, and physical activity in the treatment of osteoarthritis induced by papain

Shaiane Silva Tomazoni¹, Ernesto Cesar Pinto Leal-Junior², Lúcio Frigo³, Rodney Capp Pallotta¹, Simone Teixeira¹, Patricia de Almeida¹, Jan Magnus Bjordal⁴, Rodrigo Álvaro Brandão Lopes-Martins⁵

Abstract

Osteoarthritis (OA) is a chronic inflammatory disease and is characterized as a degenerative process. This study aimed to evaluate and compare the effects of a topical nonsteroidal anti-inflammatory drug (NSAID), physical activity, and photobiomodulation therapy (PBMT) applied alone and/or in combination between them in an experimental model of knee OA. OA was induced by injection of papain in the knees of rats. After 21 days, the animals started to be treated with the above treatment. Histological analysis shows that the experimental model of OA induction causes morphological changes consistent with the disease, and among treatments, the PBMT is the most effective for reducing these changes. Moreover, the results demonstrate that PBMT and NSAID reduce the total number of cells in the inflammatory infiltrate (p<0.05) and PBMT was the most effective for reducing the activity of myeloperoxidase (p<0.05). Finally, we observed that both NSAID and PBMT were effective for reducing the gene expression of MMP-3 (p<0.05), but in relation to the gene expression of MMP-13, PBMT was the most effective treatment (p<0.05). The results of this study indicate that PBMT is the most effective therapy in stopping disease progression, and improving inflammatory conditions observed in OA.

Photomed Laser Surg. 2006 Apr;24(2):140-50. doi: 10.1089/pho.2006.24.140.

Photobiomodulation of pain and inflammation in microcrystalline arthropathies: experimental and clinical results

F Soriano¹, V Campana, M Moya, A Gavotto, J Simes, M Soriano, R Soriano, L Spitale, J Palma

Abstract

Objective: This article presents the results of laser therapy in crystal (hydroxyapatite, calcium pyrophosphate, and urates) deposition-induced arthritis in rats and the clinical applications in humans.

Background data: Microcrystalline arthropathies are prevalent among geriatric patients, who are more vulnerable to the side effects of drugs. The effectiveness of laser therapy for pain relief, free of side effects, has been reported in painful conditions.

Methods: Two milligrams of each of the above-mentioned crystals was injected in both joints of the back limbs in three groups of rats; these groups were then treated with laser irradiation. Three other groups received no treatment after the injections. We determined the plasmatic levels of inflammatory markers (fibrinogen, prostaglandin E2, and TNF(alpha)), tissues (prostaglandin E(2)) and conducted anatomopathological studies. Twenty-five patients with acute gout arthritis were randomized into two groups and treated over 5 days: group A, diclofenac 75 mg orally, twice a day; and group B, laser irradiation once a day. Forty-nine patients with knee chronic pyrophosphate arthropathy were randomized into two groups and treated over 21 days; group A, diclofenac 50 mg orally, twice a day; and group B, laser irradiation once a day. Thirty patients with shoulder chronic hydroxyapatite arthropathy were randomized into two groups and treated over 21 days; group A, diclofenac 50 mg orally, twice a day; and group B, laser irradiation once a day.

Results: Fibrinogen, prostaglandin E(2), and TNF(alpha) concentrations in the rats injected with crystals and treated with laser decreased significantly as compared with the groups injected with crystals without treatment. Both laser therapy and diclofenac achieved rapid pain relief in patients with acute gouty arthritis without significant differences in efficacy. Laser therapy was more effective than diclofenac in patients with chronic pyrophosphate arthropathy and in patients with chronic apatite deposition disease.

Conclusion: Laser therapy represents an effective treatment in the therapeutic arsenal of microcrystalline arthropathies.

Photobiomodul Photomed Laser Surg. 2019 Sep;37(9):517-526.

Feeling the Heat: Evolutionary and Microbial Basis for the Analgesic Mechanisms of Photobiomodulation Therapy

Mark Cronshaw¹, Steven Parker¹, Praveen Arany²

Abstract

Background: The clinical therapeutic benefits of Photobiomodulation (PBM) therapy have been well established in many clinical scenarios. However, we are far from having developed a complete understanding of the underlying mechanisms of photon-biological tissue interactions. Concurrent to ongoing PBM studies, there are several parallel fields with evidences from cell and tissue physiology such as evolutionary biology, photobiology, and microbiology among others. Objective: This review is focused on extrapolating evidences from an expanded range of studies that may contribute to a better understanding of PBM mechanisms especially focusing on analgesia. Further, the choice of a PBM device source and relevant dosimetry with regards to specific mechanisms are discussed to enable broader clinical use of PBM therapies. Materials and methods: This discussion article is referenced from an expanded range of peer reviewed publications, including literature associated with evolutionary biology, microbiology, oncology, and photo-optical imaging technology, amongst others. Results and discussion: Materials drawn from many disparate disciplines is described. By inference from the current evidence base, a novel theory is offered to partially explain the cellular basis of PBM-induced analgesia. It is proposed that this may involve the activity of a class of transmembrane proteins known as uncoupling proteins. Furthermore, it is proposed that this may activate the heat stress protein response and that intracellur microthermal inclines may be of significance in PBM analgesia. It is suggested that the PBM dose response as a simple binary model of PBM effects as represented by the Arndt-Schulz law is clinically less useful than a multiphasic biological response. Finally, comments are made concerning the nature of photon to tissue interaction that can have significance in regard to the effective choice and delivery of dose to clinical target. Conclusions: It is suggested that a re-evaluation of phototransduction pathways may lead to an improvement in outcome in phototheraphy. An enhanced knowledge of safe parameters and a better knowledge of the mechanics of action at target level will permit more reliable and predictable clinical gain and assist the acceptance of PBM therapy within the wider medical community.

J Biophotonics. 2019 Oct;12(10):e201900043. doi: 10.1002/jbio.201900043. Epub 2019 Jul 9.

Analgesic effect of Photobiomodulation Therapy: An in vitro and in vivo study

Luisa Zupin¹, Giulia Ottaviani¹, Katia Rupel¹, Matteo Biasotto¹, Serena Zacchigna¹², Sergio Crovella¹³, Fulvio Celsi³

Abstract

Laser therapy, also known as Photobiomodulation (PBM) is indicated to reduce pain associated with different pathologies and applied using protocols that vary in wavelength, irradiance and fluence. Its mechanisms of action are still unclear and possibly able to directly impact on pain transmission, reducing nociceptor response. In our study, we examined the effect of two specific laser wavelengths, 800 and 970 nm, extensively applied in the clinical context and known to exert important analgesic effects. Our results point to mitochondria as the primary target of laser light in isolated dorsal root ganglion (DRG) neurons, reducing adenosine triphosphate content and increasing reactive oxygen species levels. Specifically, the 800 nm laser wavelength induced mitochondrial dysregulation, that is, increased superoxide generation and mitochondrial membrane potential. When DRG neurons were firstly illuminated by the different laser protocols and then stimulated with the natural transient receptor potential cation channel subfamily V member 1 (TRPV1) ligand capsaicin, only the 970 nm wavelength reduced the calcium response, in both amplitude and frequency. Consistent results were obtained in vivo in mice, by subcutaneous injection of capsaicin. Our findings demonstrate that the effect of PBM depends on the wavelength used, with 800 nm light mainly acting on mitochondrial metabolism and 970 nm light on nociceptive signal transmission.

Lasers Med Sci. 2018 Feb;33(2):295-304. doi: 10.1007/s10103-017-2367-7. Epub 2017 Nov 4.

Laser acupuncture-induced analgesic effect and molecular alterations in an incision pain model: a comparison with electroacupuncture-induced effects

Yen-Jing Zeng¹, Yu-Hsiang Lin², You-Cheng Wang³, Ju-Hsin Chang¹⁴, Jih-Huah Wu⁵, Sheng-Feng Hsu⁶⁷⁸, Shih-Ying Tsai⁴, Ching-Huang Lin²³, Yeong-Ray Wen⁹¹⁰¹¹¹²¹³

Abstract

Low-level laser acupuncture (LLLA) produces photobiomodulation through acupuncture point and is an alternative to low-level laser therapy. Although the analgesic effect of LLLA on chronic pain has been proven, its effect on acute postincisional pain has yet to be investigated. A plantar incision (PI) model was used to mimic human postsurgical pain. Male adult rats received GaAlAs laser irradiation at the right ST36 acupoint immediately after operation and on the following 4 days. Three laser treatment groups (two red laser groups with a 30- or 15-min treatment duration and one 30-min near-infrared laser group) were compared with sham LLLA and naive groups and an electroacupuncture (EA) group (separate study). Behavioral withdrawal thresholds of both hind paws were measured before and after incision. Expression of mitogen-activated protein kinases (p-ERK and p-p38), inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF) in the spinal cord was analyzed. All three LLLA treatments attenuated post-PI tactile allodynia in the ipsilateral paw, but only the 30-min red laser treatment affected the contralateral paw and had similar efficacy to that of EA. All laser treatments barely reduced heat hyperalgesia in both hind paws. At 3 days after PI, the 30-min red laser group showed reversed increases of PI-induced p-ERK, p-p38, and iNOS but not TNF expression in the spinal cord. Repetitive LLLA treatments ameliorated PI-induced mechanical pain. The inhibition of multiple sensitization signals highlights the unique clinical role of LLLA. Thus, LLLA is an alternative to EA as an adjuvant for postoperative pain control.

Lasers Surg Med. 2020 Apr 24. doi: 10.1002/lsm.23255. Online ahead of print.

Photobiomodulation Therapy is Able to Modulate PGE ₂ Levels in Patients With Chronic Non-Specific Low Back Pain: A Randomized Placebo-Controlled Trial

Shaiane S Tomazoni¹²³, Leonardo O P Costa¹, Jon Joensen², Martin B Stausholm², Ingvill F Naterstad², Malin Ernberg⁴, Ernesto Cesar P Leal-Junior²³⁵⁶, Jan M Bjordal²

Abstract

Background and objectives: Non-specific low back pain (LBP) is responsible for triggering increased biomarkers levels. In this way, photobiomodulation therapy (PBMT) may be an interesting alternative to treat these patients. One of the possible biological mechanisms of PBMT involved to decrease pain intensity in patients with musculoskeletal disorders is modulation of the inflammatory mediators' levels. The aim of this study was to evaluate the effects of PBMT compared with placebo on inflammatory mediators' levels and pain intensity in patients with chronic non-specific LBP.

Study design/materials and methods: A prospectively registered, randomized triple-blinded (volunteers, therapists, and assessors), placebo-controlled trial was performed. Eighteen patients with chronic non-specific LBP were recruited and treated with a single session of active PBMT or placebo PBMT. The primary outcome of the study was serum prostaglandin E₂ levels and the secondary outcomes were tumor necrosis factor-α, interleukin-6 levels, and pain intensity. All outcomes were measured before and after 15 minutes of treatment session.

Results: PBMT was able to decrease prostaglandin E₂ levels at post-treatment compared with placebo, with a mean difference of -1470 pg/ml, 95% confidence interval -2906 to -33.67 in patients with LBP. There was no difference between groups in the other measured outcomes. Patients did not report any adverse events.

Conclusion: Our results suggest that PBMT was able to modulate prostaglandin E₂ levels, indicating that this may be one of the mechanisms involved in the analgesic effects of PBMT in patients with LBP. Trial registration number (ClinicalTrials.gov): NCT03859505. Lasers Surg. Med. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals, Inc.

Lasers Med Sci. 2019 Jun;34(4):793-800. doi: 10.1007/s10103-018-2665-8. Epub 2018 Oct 17.

Laser photobiomodulation is more effective than ultrasound therapy in patients with chronic nonspecific low back pain: a comparative study

Sayed A Tantawy¹², Walid K Abdelbasset³⁴, Dalia M Kamel⁵⁶, Saud M Alrawaili³, Saud F Alsubaie³

Abstract

The purpose of this study was to compare the effects of laser photobiomodulation therapy (lPBMt) and ultrasound therapy (UST) in patients with chronic non-specific low back pain (CNLBP). Forty-five patients with CNLBP aged 30-40 years were divided randomly into three groups of 15 subjects each. The lPBMt group received 8 weeks of lPBMt with an exercise program, while the UST group received 8 weeks of UST with the same exercise program; the control group received only the exercise program for 8 weeks. Pain, disability, functional performance, and lumbar range of motion were assessed at the beginning of the study and after 8 weeks. There were no significant differences in demographic and clinical characteristics among the three groups at baseline (p > 0.05). At the end of the study, there were significant improvements in pain, disability, and functional performance in the two experimental groups (p < 0.05), but changes in the control group were non-significant. However, lumbar range of motion was significantly improved only in the lPBMt group (p < 0.05). When the three groups were compared in terms of a change in clinical variables, there was a significant difference among the three groups in all measures in favor of lPBMt group. Based on our results, both lPBMt or UST combined with an 8-week exercise program seemed to be effective methods for decreasing pain, reducing disability, and increasing functional performance in patients with CNLBP, although lPBMt is more effective than UST.

Laser Ther. 2018 Sep 30;27(3):167-173. doi: 10.5978/islsm.27_18-OR-18.

A case control series for the effect of photobiomodulation in patients with low back pain and concurrent depression

Charles Philip Gabel¹, Samuel R Petrie², David Mischoulon², Michael R Hamblin³⁴, Albert Yeung², Lisa Sangermano², Paolo Cassano²⁵

Abstract

Background and aims: To present incidental findings in patients with low back pain (LBP) who received photobiomodulation (PBM) administered to the back and thighs as an adjunct to physical therapy (PT) and then experienced improvement in concurrent depression.

Materials and methods: Five outpatients with LBP and concurrent self-reported depression were treated for LBP over five weeks with PT (5-sessions) and concurrent PBM (final 3-sessions), and retrospectively matched to five control patients treated with PT alone (5-sessions). The PBM device emitted light at 850nm and 660 nm with an irradiance of 100 mW/cm² and fluence of 3 J/cm² on 12 symmetrical posterior sites (thoracic, lumbar and thighs) for 30 sec/site.

Results: Both groups had non-significant differences in all baseline scores, except for higher functional status (ARGS) in the PBM-group (33.6 ± 12.2 vs.18.6 ± 3.6, t(8) = 2.638, p = 0.030). After treatment, the mean decrease in depression scores (OMSQ-12 item #6) was significantly larger in the PBM-group (43.0 ± 22.0 vs. 8.0 ± 5.7, t(8) = 3.449, p = 0.009). Improvement in functional status (ARGS) in the PBM-group was similar to that in the controls (42.0 ± 13.5 vs. 43.4 ± 11.1, t(8) = 0.179, p = 0.862), suggesting group differences in antidepressant effect were independent of functional status improvement.

Conclusions: This preliminary investigation suggests that an antidepressant effect may result from PBM to the back and thighs in patients with LBP and concurrent depression.

Open Orthop J. 2013; 7: 396–419. Published online 2013 Sep 20. doi: 10.2174/1874325001307010396

Low Level Laser Therapy (LLLT) for Neck Pain: A Systematic Review and Meta-Regression

Anita R Gross,^*,1 Stephanie Dziengo,³ Olga Boers,³ Charlie H Goldsmith,² Nadine Graham,¹ Lothar Lilge,⁴ Stephen Burnie,³ and Roger White⁵, for the Cervical Overview Group^§

Go to:

Abstract

Purpose:

This systematic review update evaluated low level laser therapy (LLLT) for adults with neck pain.

Methods:

Computerized searches (root up to Feb 2012) included pain, function/disability, quality of life (QoL) and global perceived effect (GPE). GRADE, effect-sizes, heterogeneity and meta-regression were assessed.

Results:

Of 17 trials, 10 demonstrated high risk of bias. For chronic neck pain, there was moderate quality evidence (2 trials, 109 participants) supporting LLLT over placebo to improve pain/disability/QoL/GPE up to intermediate-term (IT). For acute radiculopathy, cervical osteoarthritis or acute neck pain, low quality evidence suggested LLLT improves ST pain/function/QoL over a placebo. For chronic myofascial neck pain (5 trials, 188 participants), evidence was conflicting; a meta-regression of heterogeneous trials suggests super-pulsed LLLT increases the chance of a successful pain outcome.

Conclusions:

We found diverse evidence using LLLT for neck pain. LLLT may be beneficial for chronic neck pain/function/QoL. Larger long-term dosage trials are needed.

Purpose:

This systematic review update evaluated low level laser therapy (LLLT) for adults with neck pain.

Methods:

Results:

Conclusions:

We found diverse evidence using LLLT for neck pain. LLLT may be beneficial for chronic neck pain/function/QoL. Larger long-term dosage trials are needed.

Lancet. 2009 Dec 5;374(9705):1897-908. doi: 10.1016/S0140-6736(09)61522-1. Epub 2009 Nov 13.

Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised placebo or active-treatment controlled trials

Roberta T Chow¹, Mark I Johnson, Rodrigo A B Lopes-Martins, Jan M Bjordal

Abstract

Background: Neck pain is a common and costly condition for which pharmacological management has limited evidence of efficacy and side-effects. Low-level laser therapy (LLLT) is a relatively uncommon, non-invasive treatment for neck pain, in which non-thermal laser irradiation is applied to sites of pain. We did a systematic review and meta-analysis of randomised controlled trials to assess the efficacy of LLLT in neck pain.

Methods: We searched computerised databases comparing efficacy of LLLT using any wavelength with placebo or with active control in acute or chronic neck pain. Effect size for the primary outcome, pain intensity, was defined as a pooled estimate of mean difference in change in mm on 100 mm visual analogue scale.

Findings: We identified 16 randomised controlled trials including a total of 820 patients. In acute neck pain, results of two trials showed a relative risk (RR) of 1.69 (95% CI 1.22-2.33) for pain improvement of LLLT versus placebo. Five trials of chronic neck pain reporting categorical data showed an RR for pain improvement of 4.05 (2.74-5.98) of LLLT. Patients in 11 trials reporting changes in visual analogue scale had pain intensity reduced by 19.86 mm (10.04-29.68). Seven trials provided follow-up data for 1-22 weeks after completion of treatment, with short-term pain relief persisting in the medium term with a reduction of 22.07 mm (17.42-26.72). Side-effects from LLLT were mild and not different from those of placebo.

Interpretation: We show that LLLT reduces pain immediately after treatment in acute neck pain and up to 22 weeks after completion of treatment in patients with chronic neck pain.

Kaohsiung J Med Sci. 2019 Nov;35(11):702-707. doi: 10.1002/kjm2.12113. Epub 2019 Aug 7.

Immediate responses of multi-focal low level laser therapy on quadriceps in knee osteoarthritis patients.

Li CF¹, Chen YJ^1,2, Lin TY³, Hsiao YH¹, Fu JC¹, Chen CH^1,4,5, Lee CL⁶.

Abstract

Low-level laser therapy (LLLT) applying on knee osteoarthritis (OA) patients has shown positive outcomes in analgesic effect and functional recovery. However, few studies applied such therapy on large area of quadriceps muscle in these patients. The aim of this study was to evaluate immediate effect of multi-focal LLLT on quadriceps of knee OA patients in pain and functional performance. Fifty-one participants with knee OA were enrolled and evaluated before (T1) and immediately after intervention (T2) by knee joint pain in numeric rating scale (NRS), walking speed, timed five-chair stands, and quadriceps strength by isokinetic dynamometer. Intervention with two multi-focal Gallium-Aluminum-Arsenide laser devices, each device with 36 laser diodes (wavelength 808 ± 10 nm, continuous, mean power 50 mW, 30 minutes), applied simultaneously over bilateral quadriceps with a total dose of 180 J for each thigh. The multi-focal LLLT significantly improved knee joint pain as measured by the NRS (54% reduction), timed five-chair stands, and walking speed (P < .05). Knee extensor strength also increased in terms of peak torque and force of concentric and eccentric contraction as measured by isokinetic dynamometer (P < .05). In conclusion, single-session multi-focal LLLT on quadriceps in knee OA patients has immediate beneficial effect on knee pain reduction, quadriceps strengthening and functional performance recovery. Long-term effect requires further investigation. Multi-focal LLLT on quadriceps might serve as an alternative non-invasive treatment option in these patients.

Laser Ther. 2014 Dec 27; 23(4): 273–277. doi: 10.5978/islsm.14-OR-21

Low Level Laser Therapy for chronic knee joint pain patients

Takashi Nakamura,¹ Satoru Ebihara,² Ikuko Ohkuni,² Hideaki Izukura,² Takashi Harada,² Nobuyuki Ushigome,² Toshio Ohshiro,³ Yoshiro Musha,⁴ Hiroshi Takahashi,¹ Kazuaki Tsuchiya,¹ and Ayako Kubota¹

Abstract

Background and Aims: Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain.

Materials and Methods: Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy. A 1000 mW semi-conductor laser device was used to deliver 20.1 J/cm² per point in continuous wave at 830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks.

Results: A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment regimen a significant improvement was observed (p<0.001). After treatment, no significant differences were observed in the knee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment.

Conclusion: The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.

Lasers Surg Med. 2018 Oct;50(8):819-828. doi: 10.1002/lsm.22939. Epub 2018 May 7.

Incorporation of photobiomodulation therapy into a therapeutic exercise program for knee osteoarthritis: A placebo-controlled, randomized, clinical trial

Cid A F de Paula Gomes¹, Ernesto C P Leal-Junior², Almir V Dibai-Filho³, Adriano R de Oliveira¹, André S Bley⁴, Daniela A Biasotto-Gonzalez¹, Paulo de Tarso Camillo de Carvalho¹

Abstract

Objective: To investigate the clinical effects of incorporation of phototherapy in a therapeutic exercise program for individuals with knee osteoarthritis (OA) when compared to a group that received exercise alone and to a group that received exercise + placebo phototherapy.

Materials and methods: This is a randomized, blinded and placebo-controlled trial. Thus, sixty male and female individuals aged 40-80 years with knee pain in the previous 6 months participated of the study, with diagnosis of unilateral knee OA based on the criteria established by the American College of Rheumatology and radiographic confirmation and Grades 2 or 3 of the Kellgren-Lawrence Classification. The individuals were equally divided in the groups exercise alone, exercise + active phototherapy (nine-diode cluster device: one 905 nm super-pulsed diode laser, four 875 nm LED and four 640 nm LED; energy per quadrant: 7.85 J; total energy: 23.55 J per session), or exercise + placebo phototherapy. Treatments were performed twice a week for 5 consecutive weeks. Patients were evaluated before and after the sessions of treatment. The outcome measures were: Western Ontario and McMaster University Osteoarthritis Index (WOMAC), Lower Extremity Functional Scale (LEFS), Numerical Rating Pain Scale (NRPS), pressure pain threshold (PPT) in two points of knee, muscle strength, and the Functional Reach Test (FRT).

Results: Exercise + active phototherapy was significantly more effective than exercise alone (mean difference [MD] = 2.75, 95% confidence interval [CI] = 3.17 to 2.32) and exercise + placebo phototherapy (MD = 2.38, 95% CI = 2.79 to 1.96) only with regard to the NRPS, considering minimal clinically important difference. No clinical significant results were found for function, the pressure pain threshold, muscle strength or balance.

Conclusions: The combination of phototherapy and an exercise program is effective at reducing pain intensity among individuals with knee osteoarthritis than exercise alone or exercise + placebo phototherapy in a short-term protocol. Lasers Surg. Med. 50:819-828, 2018.

Photomed Laser Surg. 2006 Apr;24(2):101-10.

Photobiomodulation of pain in carpal tunnel syndrome: review of seven laser therapy studies.

Naeser MA¹

Abstract

In this review, seven studies using photoradiation to treat carpal tunnel syndrome (CTS) are discussed: two controlled studies that observed real laser to have a better effect than sham laser, to treat CTS; three openprotocol studies that observed real laser to have a beneficial effect to treat CTS; and two studies that did not observe real laser to have a better effect than a control condition, to treat CTS. In the five studies that observed beneficial effect from real laser, higher laser dosages (9 Joules, 12-30 Joules, 32 J/cm(2), 225 J/cm(2)) were used at the primary treatment sites (median nerve at the wrist, or cervical neck area), than dosages in the two studies where real laser was not observed to have a better effect than a control condition (1.8 Joules or 6 J/cm(2)). The average success rate across the first five studies was 84% (SD, 8.9; total hands = 171). The average pain duration prior to successful photoradiation was 2 years. Photoradiation is a promising new, conservative treatment for mild/moderate CTS cases (motor latency < 7 msec; needle EMG, normal). It is cost-effective compared to current treatments.

Medicine (Baltimore). 2016 Aug;95(31):e4424. doi: 10.1097/MD.0000000000004424.

Effectiveness of low-level laser on carpal tunnel syndrome: A meta-analysis of previously reported randomized trials.

Li ZJ¹, Wang Y, Zhang HF, Ma XL, Tian P, Huang Y.

Abstract

BACKGROUND:

Low-level laser therapy (LLLT) has been applied in the treatment of carpal tunnel syndrome (CTS) for an extended period of time without definitive consensus on its effectiveness. This meta-analysis was conducted to evaluate the effectiveness of low-level laser in the treatment of mild to moderate CTS using a Cochrane systematic review.

METHODS:

We conducted electronic searches of PubMed (1966-2015.10), Medline (1966-2015.10), Embase (1980-2015.10), and ScienceDirect (1985-2015.10), using the terms "carpal tunnel syndrome" and "laser" according to the Cochrane Collaboration guidelines. Relevant journals or conference proceedings were searched manually to identify studies that might have been missed in the database search. Only randomized clinical trials were included, and the quality assessments were performed according to the Cochrane systematic review method. The data extraction and analyses from the included studies were conducted independently by 2 reviewers. The results were expressed as the mean difference (MD) with 95% confidence intervals (CI) for the continuous outcomes.

RESULTS:

Seven randomized clinical trials met the inclusion criteria; there were 270 wrists in the laser group and 261 wrists in the control group. High heterogeneity existed when the analysis was conducted. Hand grip (at 12 weeks) was stronger in the LLLT group than in the control group (MD = 2.04; 95% CI: 0.08-3.99; P = 0.04; I = 62%), and there was better improvement in the visual analog scale (VAS) (at 12 weeks) in the LLLT group (MD = 0.97; 95% CI: 0.84-1.11; P < 0.01; I = 0%). The sensory nerve action potential (SNAP) (at 12 weeks) was better in the LLLT group (MD = 1.08; 95% CI: 0.44-1.73; P = 0.001; I = 0%). However, 1 included study was weighted at >95% in the calculation of these 3 parameters. There were no statistically significant differences in the other parameters between the 2 groups.

CONCLUSION:

This study revealed that low-level laser improve hand grip, VAS, and SNAP after 3 months of follow-up for mild to moderate CTS. More high-quality studies using the same laser intervention protocol are needed to confirm the effects of low-level laser in the treatment of CTS.

Tissue Cell. 2017 Aug;49(4):483-488. doi: 10.1016/j.tice.2017.05.006. Epub 2017 Jun 3.

Low level laser therapy accelerates the extracellular matrix reorganization of inflamed tendon.

Da Ré Guerra F¹, Vieira CP², Marques PP³, Oliveira LP⁴, Pimentel ER⁴.

Abstract

In tendon lesions, inflammation indicates the beginning of tissue repair and influences cell proliferation and the remodeling of the extracellular matrix (ECM). Low level laser (LLL) therapy has been an important method to induce tissue repair, and several studies have sought to better understand the therapeutic possibilities of this modality. This study analyzed the effect of LLL on the ECM of rat tendons during the early phase of the inflammatory process. Wistar rats received an intratendinous application of carrageenan adjacent to the osteotendinous region in the right paw. The animals were divided into the following groups: G1-intact, G2-animals with no treatment after the inflammation induction, G3-animals treated with LLL 1 and 3h after induction of inflammation (4J/cm² continuous). After 4h of application, the animals of the two groups were euthanized with isoflurane overdose. Our results demonstrate that LLL therapy can promote decrease in non-collagenous protein and glycosaminoglycans content, as well as an increase in metalloproteinases -9, which proved, for the first time, that LLL therapy promotes alterations in the inflamed tendons even when analyzed only four hours after this process occur and could be a useful tool to improve the balance in inflamed tissues.

Lasers Med Sci. 2013 Sep;28(5):1281-8. doi: 10.1007/s10103-012-1236-7. Epub 2012 Nov 21.

LLLT improves tendon healing through increase of MMP activity and collagen synthesis.

Guerra Fda R¹, Vieira CP, Almeida MS, Oliveira LP, de Aro AA, Pimentel ER.

Abstract

The Achilles tendon has a high incidence of rupture, and the healing process leads to a disorganized extracellular matrix (ECM) with a high rate of injury recurrence. To evaluate the effects of different conditions of low-level laser (LLL) application on partially tenotomized tendons, adult male rats were divided into the following groups: G1, intact; G2, injured; G3, injured + LLL therapy (LLLT; 4 J/cm(2) continuous); G4, injured + LLLT (4 J/cm(2), 20 Hz); G5, injured; G6, injured + LLLT (4 J/cm(2) continuous); and G7, injured + LLLT (4 J/cm(2), 20 Hz until the 7th day and 2 kHz from 8 to 14 days). G2, G3, and G4 were euthanized 8 days after injury, and G5, G6, and G7 were euthanized on the 15th day. The quantification of hydroxyproline (HOPro) and non-collagenous protein (NCP), zymography for matrix metalloproteinase (MMP)-2 and MMP-9, and Western blotting (WB) for collagen types I and III were performed. HOPro levels showed a significant decrease in all groups (except G7) when compared with G1. The NCP level increased in all transected groups. WB for collagen type I showed an increase in G4 and G7. For collagen type III, G4 presented a higher value than G2. Zymography for MMP-2 indicated high values in G4 and G7. MMP-9 increased in both treatment groups euthanized at 8 days, especially in G4. Our results indicate that the pulsed LLLT improved the remodeling of the ECM during the healing process in tendons through activation of MMP-2 and stimulation of collagen synthesis.

Lasers Med Sci. 2016 May;31(4):759-66. doi: 10.1007/s10103-016-1918-7. Epub 2016 Mar 16.

Low-level laser therapy modulates pro-inflammatory cytokines after partial tenotomy.

Da Ré Guerra F¹, Vieira CP², Oliveira LP², Marques PP³, dos Santos Almeida M⁴, Pimentel ER².

Abstract

Tendon injuries give rise to substantial morbidity, and current understanding of the mechanisms involved in tendon injury and repair is limited. This lesion remains a clinical issue because the injury site becomes a region with a high incidence of recurrent rupture and has drawn the attention of researchers. We already demonstrated that low-level laser therapy (LLLT) stimulates the synthesis and organization of collagen I, MMP-9, and MMP-2 and improved the gait recovery of the treated animals. The aim of this study was to evaluate the effects of LLLT in the nitric oxide and cytokines profile during the inflammatory and remodeling phases. Adult male rats were divided into the following groups: G1--intact, G2-- injured, G3--injured + LLLT (4 J/cm(2) continuous), G4--injured + LLLT (4 J/cm(2)-20 Hz--pulsed laser). According to the analysis, the animals were euthanized on different dates (1, 4, 8, or 15 days after injury). ELISA assay of TNF-α, IL-1β, IL-10, and TGF-β was performed. Western blotting of isoform of nitric oxide synthase (i-NOS) and nitric oxide dosage experiments was conducted. Our results showed that the pulsed LLLT seems to exert an anti-inflammatory effect over injured tendons, with reduction of the release of proinflammatory cytokines, such as TNF-α and the decrease in the i-NOS activity. Thanks to the pain reduction and the facilitation of movement, there was a stimulation in the TGF-β and IL-1β release. In conclusion, we believe that pulsed LLLT worked effectively as a therapy to reestablish the tendon integrity after rupture.

Arq Neuropsiquiatr. 2018 Oct;76(10):663-667. doi: 10.1590/0004-282X20180109.

Botulinum toxin A (BT-A) versus low-level laser therapy (LLLT) in chronic migraine treatment: a comparison.

Loeb LM¹, Amorim RP¹, Mazzacoratti MDGN², Scorza FA¹, Peres MFP³.

Abstract

OBJECTIVE:

The aim of this work was to evaluate patients with chronic migraine treated with botulinum toxin A (BT-A) and compare this with low level laser therapy (LLLT), referencing: pain days, pain intensity, intake of drugs/self-medication, anxiety and sleep disorders.

METHODS:

Patients were randomized into two groups: BT-A group (n = 18) and LLLT group (n = 18). Each patient kept three pain diaries: one before (baseline) (30 days), one during treatment (30 days) and one after the post-treatment phase (30 days). Repeated ANOVA plus the Bonferroni post-test, Student's t test, and factorial analysis were applied, and p < 0.05 was accepted as significant.

RESULTS:

Our data showed that both treatments were able to reduce headache days, acute medication intake and decrease the intensity of pain. Anxiety was reduced in the BT-A group, while sleep disturbance was reduced in the LLLT group.

CONCLUSION:

Our data showed that both treatments can be used to treat chronic migraine, without notable differences between them.

J Oral Facial Pain Headache. 2020 Winter;34(1):13–30. doi: 10.11607/ofph.2310. Epub 2019 Jul 24.

Efficacy of Low-Level Laser Therapy for the Therapeutic Management of Neuropathic Orofacial Pain: A Systematic Review.

de Pedro M, López-Pintor RM, de la Hoz-Aizpurua JL, Casañas E, Hernández G.

Abstract

AIMS:

To evaluate the efficacy of low-level laser therapy (LLLT) for the therapeutic management of neuropathic orofacial pain.

METHODS:

This systematic review was conducted according to PRISMA guidelines. A comprehensive search of the literature was conducted in the PubMed/MEDLINE, Scopus, and Cochrane Library databases up to March 8, 2018, using terms such as low-level laser therapy, neuropathic pain, orofacial pain, neuralgia, neuropathy, and all the entities described in section 13 of the International Classification of Headache Disorders, third edition. The primary outcome was measurement of pain intensity.

RESULTS:

A total of 997 studies were obtained with the initial search; 13 (8 randomized controlled trials, 2 prospective studies, and 3 case series) met the inclusion criteria and were analyzed for data extraction. Three provided data for the treatment of trigeminal neuralgia, 1 for occipital neuralgia, and 10 for burning mouth syndrome. All studies showed a reduction in pain intensity (most of them significant). The different studies analyzed LLLT alone and compared to placebo, to another treatment, or to different LLLT application protocols.

CONCLUSION:

LLLT seems to be effective as a treatment option for different neuropathic orofacial pain entities such as trigeminal neuralgia, occipital neuralgia, and burning mouth syndrome as a single or combined treatment. However, more quality studies assessing all outcome measures of chronic pain are needed in the medium and long terms. Furthermore, due to the lack of standardization of the application technique, more well-designed studies are required to confirm the results of this systematic review.

Photobiomodul Photomed Laser Surg. 2019 Dec;37(12):826-836. doi: 10.1089/photob.2019.4705. Epub 2019 Nov 26.

Photobiomodulation in Temporomandibular Disorders.

Tunér J¹, Hosseinpour S², Fekrazad R^3,4.

Abstract

Objective: This systematic review aimed to comprehensively review all available documents regarding photobiomodulation therapy (PBMT) application in temporomandibular disorder (TMD) patients and to suggest an evidence-based protocol for therapeutic PBM administration for these patients. Background data: The existence of temporomandibular joint and/or pain and dysfunction in masticatory muscles is characterized in TMDs. PBMT is, due to its impact on biological processes, especially inflammation, considered as an adjuvant treatment modality in TMD cases. Materials and methods: All original articles related to PBMT for TMDs in EMBASE, MEDLINE (NCBI PubMed and PMC), Cochrane library, Scopus, Web of Science, and Google Scholar were reviewed until December 2018. Results: The energy density ranging from 0.75 to 112.5 J/cm² with 0.9-500 mW power was found to be a window protocol for light application. The best results for pain relief and mandibular movement enhancement were reported after application of GaAlAs diode laser, 800-900 nm, 100-500 mW, and <10 J/cm², twice a week for 30 days on trigger points. The session of light applications varied from 1 to 20. Conclusions: Although most articles showed that PBMT is effective in reducing pain and contributed to functional enhancement in TMD patients, the heterogenic parameters that have been reported in various studies made the standardization of PBMT complicated. However, such evidence-based consensus can be beneficial for both future research and for clinical applications.

Indian J Dent Res. 2020 Jan-Feb;31(1):42-47. doi: 10.4103/ijdr.IJDR_735_18.

Comparative efficacy of low-Level laser and TENS in the symptomatic relief of temporomandibular joint disorders: A randomized clinical trial.

Chellappa D¹, Thirupathy M¹.

Abstract

AIM:

Temporomandibular disorders (TMDs) comprise a number of signs and symptoms affecting the masticatory muscles, temporomandibular joint (TMJ), or both. Because of the multifactorial etiology of such problems, the treatment usually involves more than one modality.

OBJECTIVES:

Therefore, the aim of this study was to compare the effectiveness of transcutaneous electric nerve stimulation (TENS) and low-level laser therapy for the treatment of patients with TMD. Materials and Methods: The clinical trial was performed with 60 patients diagnosed with TMD of multiple causes. All the patients received both methods of treatment in 6 consecutive weeks. A paired t-test was applied to verify the significance of the results. Results: A significant improvement in the range of motion and pain relief for both the therapies was observed.

CONCLUSIONS:

Comparatively after analyzing the two methods, the values obtained after LLLT were significantly higher than those obtained after TENS therapy (P < 0.01).

Cranio. 2017 Nov;35(6):372-378. doi: 10.1080/08869634.2017.1292176. Epub 2017 Feb 20.

Do TMJ symptoms improve and last across time after treatment with red (660 nm) and infrared (790 nm) low level laser treatment (LLLT)? A survival analysis.

Douglas De Oliveira DW¹, Lages FS¹, Guimarães RC², Pereira TS², Botelho AM³, Glória JCR³, Tavano KTA³, Gonçalves PF³, Flecha OD³.

Author information

Abstract

OBJECTIVE:

Temporomandibular disorder (TMD) is a variety of clinical problems that originate from the area of the temporomandibular joint (TMJ), masticatory muscles, and surrounding tissues. There are different treatment options; however, there is no evidence that low level laser treatment (LLLT) will last about six months. The aim of this study was to determine the survival rate of treatment with red (660 nm) and infrared (790 nm) laser in cases of TMDs.

METHODS:

In 19 subjects, one side of the face (half face) was randomly selected to receive intervention, in a total of 116 sensitive points. Pain was measured at baseline and time intervals of 24 h, 30, 90, and 180 days after treatment. Laser irradiation with 4 j/cm² in the TMJs and 8 j/cm² in the muscles was used in three sessions. Kaplan-Meier survival analysis and logistic regression were performed.

RESULTS:

Both treatments showed statistically significant results (p < 0.001). The survival rate for red and infrared laser was 0.24 and 0.30, respectively, at 180 days. Grinding teeth and headache were associated with recurrent pain.

DISCUSSION:

Both lasers were effective in the treatment of TMD symptoms and had a low survival rate at 180 days.

Braz Oral Res. 2017 Dec 18;31:e107. doi: 10.1590/1807-3107bor-2017.vol31.0107.

The analgesic effect of photobiomodulation therapy (830 nm) on the masticatory muscles: a randomized, double-blind study

Sabrina Araújo Pinho Costa¹, Giovanna Piacenza Florezi¹, Gisele Ebling Artes¹, Jessica Ribeiro da Costa¹, Rosane Tronchin Gallo¹, Patricia Moreira de Freitas², Andrea Lusvarghi Witzel¹

Abstract

This study assesses the efficacy of photobiomodulation therapy (830 nm) for myalgia treatment of masticatory muscles. Sixty patients with muscular myalgia were selected and randomly allocated into 2 groups (n=30): Group A comprised patients given a placebo (control), and Group B consisted of those undergoing photobiomodulation therapy (PBMT). PBMT and placebo were applied bilaterally to specific points on the masseter and temporal muscles. Referred pain elicited by palpation and maximum mouth opening were measured before (EV1) and after (EV2) the treatments. The data were analyzed using statistical tests, considering a significance level of 5%. No significant differences in range were observed for active or passive mouth opening (p ≥ 0.05). Comparing the final outcomes (EV1-EV2) of both treatments, statistical significance was verified for total pain in the right masseter muscle (p = 0.001) and total pain (p = 0.005). In EV2, significant differences in pain reported with palpation were found between Groups A and B for the following: left posterior temporal muscle (p = 0.025), left superior masseter muscle (p = 0.036), inferior masseter muscle (p = 0.021), total pain (left side) (p = 0.009), total masseter muscle (left side) (p = 0.014), total temporal (left side) (p = 0.024), and total pain (p = 0.035). We concluded that PBMT (830 nm) reduces pain in algic points, but does not influence the extent of mouth opening in patients with myalgia.

Med Oral Patol Oral Cir Bucal. 2020 Mar; 25(2): e277–e282.

Published online 2020 Jan 22. doi: 10.4317/medoral.23336

Evaluation of effectiveness of photobiostimulation in alleviating side effects after dental implant surgery. A randomized clinical trial

Gianluigi Caccianiga,¹ Letizia Perillo,² Marco Portelli,³ Marco Baldoni,⁴ Cosimo Galletti,⁵ and Cosme Gay-Escoda⁶

Abstract

Go to:

Background

To assess if photobiostimulation (PBS) alleviates pain intensity/duration and swelling after implant surgery.

Material and Methods

Sixty subjects (27 male and 33 female, with a mean age of 47,13 8.05 years) were included and randomly assigned to experimental group (implant surgery and photobiostimulation), placebo group (implant surgery and simulated photobiostimulation) and control group (implant surgery only). Inclusion criteria: subjects older than 20 years, with a healthy oral mucosa and requiring implant surgery. Exclusion criteria: pregnancy, history of implant failure, light sensitivity, metabolic deseases, consumption of antibiotics or corticosteroids in the last two weeks, smokers and alcohol drinkers. Patients reported the pain experienced by using a numeric rating scale (NRS) at 2 hours, 6 hours, 12 hours, 24 hours and from day 2 to 7. Swelling score was assessed by linear measurements and type and number of analgesic drugs within each time-point were recorded on a spreadsheet. Data of pain and amount of swelling were compared among the three groups by using the Kruskal-Wallis H Test and post-hoc comparisons tests.

Results

Pain in the experimental group was less compared to controls and placebo group, at each time intervals (p < 0.001) as well as the maximum pain score (experimental group: median = 2, interquartile range 2-3; control group: median = 8, interquartile range 3,75-9; placebo group: median = 8, interquartile range 6,25-9). Swelling was almost insignificant in the experimental group (maximum value = 1, interquartile range 0-2,75, at 24 hours) compared with control (maximum value = 6, interquartile range 5-8,75, at 24 hours) and placebo (maximum value = 6, interquartile range 5-8, at 24 hours). Subjects in the experimental group assumed less analgesics compared to both controls and placebo groups.

Conclusions

Photobiostimulation is an effective method to reduce pain intensity/duration and swelling after implant surgery.

Background

To assess if photobiostimulation (PBS) alleviates pain intensity/duration and swelling after implant surgery.

Material and Methods

Results

Conclusions

Photobiostimulation is an effective method to reduce pain intensity/duration and swelling after implant surgery.

Lasers Med Sci. 2020 Jun;35(4):971-978. doi: 10.1007/s10103-019-02929-8. Epub 2019 Dec 7.

Comparison of the effect of photobiomodulation therapy and Ibuprofen on postoperative pain after endodontic treatment: randomized, controlled, clinical study

Eduardo Costa Nunes¹, Fernando José Herkrath², Eduardo Hideki Suzuki¹, Erivan Clementino Gualberto Júnior¹, André Augusto Franco Marques¹, Emílio Carlos Sponchiado Júnior³

Abstract

The aim of the study was to compare the effect of Ibuprofen and the application of photobiomodulation therapy protocol on the reduction of postoperative pain in endodontically treated teeth using a randomized clinical trial design. Seventy patients, diagnosed with symptomatic irreversible pulpitis, were selected. Treatment was performed by a single operator; a reciprocal system was used to prepare the canals; they were obturated using the Tagger's hybrid technique and coronally sealed with glass-ionomer cement. After treatment, patients were randomly divided into 2 groups. In the active control group, two Ibuprofen 600 mg tablets were administered within a 12-h interval. In the photobiomodulation therapy group, the irradiation was applied after treatment. The evaluation of postoperative pain was performed by another researcher blinded to the groups at 6, 12, 24, and 72 h intervals after treatment. To measure the outcome, two pain scales were used: numerical rate scale (NRS) and verbal rate scale (VRS). Data were analyzed using the chi-square, Mann-Whitney, and Wilcoxon paired tests. Outcome was superior with photobiomodulation therapy at 6 h (p < 0.001), 12 h (p = 0.005), and 24 h (p < 0.001) intervals compared with Ibuprofen. The results for the 72 h (p = 0.317) interval were similar, both in the VRS and NRS scales. It may be concluded that the use of photobiomodulation therapy was effective in reducing pain within the first 24 h when compared with the administration of Ibuprofen 600 mg.

Int J Oral Sci. 2018 Jul 2;10(3):22. doi: 10.1038/s41368-018-0023-0.

Effect of low-level laser therapy on tooth-related pain and somatosensory function evoked by orthodontic treatment.

Wu S^1,2, Chen Y¹, Zhang J³, Chen W⁴, Shao S², Shen H², Zhu L⁵, Ye P⁶, Svensson P^7,8,9, Wang K¹⁰.

Abstract

Low-level laser therapy (LLLT) may have an effect on the pain associated with orthodontic treatment. The aim of this study was to evaluate the effect of LLLT on pain and somatosensory sensitization induced by orthodontic treatment. Forty individuals (12-33 years old; mean ± standard deviations: 20.8 ± 5.9 years) scheduled to receive orthodontic treatment were randomly divided into a laser group (LG) or a placebo group (PG) (1:1). The LG received LLLT (810-nm gallium-aluminium-arsenic diode laser in continuous mode with the power set at 400 mW, 2 J·cm^-2) at 0 h, 2 h, 24 h, 4 d, and 7 d after treatment, and the PG received inactive treatment at the same time points. In both groups, the non-treated side served as a control. A numerical rating scale (NRS) of pain, pressure pain thresholds (PPTs), cold detection thresholds (CDTs), warmth detection thresholds (WDTs), cold pain thresholds (CPTs), and heat pain thresholds (HPTs) were tested on both sides at the gingiva and canine tooth and on the hand. The data were analysed by a repeated measures analysis of variance (ANOVA). The NRS pain scores were significantly lower in the LG group (P = 0.01). The CDTs, CPTs, WDTs, HPTs, and PPTs at the gingiva and the PPTs at the canine tooth were significantly less sensitive on the treatment side of the LG compared with that of the PG (P < 0.033). The parameters tested also showed significantly less sensitivity on the non-treatment side of the LG compared to that of the PG (P < 0.043). There were no differences between the groups for any quantitative sensory testing (QST) measures of the hand. The application of LLLT appears to reduce the pain and sensitivity of the tooth and gingiva associated with orthodontic treatment and may have contralateral effects within the trigeminal system but no generalized QST effects. Thus, the present study indicated a significant analgesia effect of LLLT application during orthodontic treatment. Further clinical applications are suggested.

Int Orthod. 2020 Mar;18(1):69-78. doi: 10.1016/j.ortho.2019.09.004. Epub 2019 Oct 31.

Photobiomodulation as oedema adjuvant in post-orthognathic surgery patients: A randomized clinical trial

Angela Domínguez Camacho¹, Sergio Andrés Velásquez², Neftalí Joaquín Benjumea Marulanda³, Mauricio Moreno³

Abstract

Objective: Photobiomodulation therapy (PBMT) has been used in multiple applications in general medicine as powerful anti-inflammatory, analgesic and reducing oedema in different parts of the body. The aim of this study is to compare the effect on post-surgical oedema after mandibular orthognathic surgery, between two different laser power densities and oral medication with non-steroidal anti-inflammatory.

Materials and methods: In a randomized clinical trial, on 60 patients who were subject to mandibular orthognathic surgery were divided into three groups. All groups received sodium naproxen 250mg every 8hours for 6days. Two groups were irradiated with two different laser application protocols and the other was a control group. In G1 group the irradiation parameters three times per week for two weeks were: 940nm, in continuous mode, 2.5W, 120s, 85.71J/cm², 0.89W/cm², over the right and left side with a distance from the skin surface of 1mm with the whitening handpiece (spot size of 2.8cm²). In G2, the irradiation parameters three times a week for two weeks were: 940nm, in continuous mode, 4.1W, 120s, 68.33J/cm², 0.58W/cm² over the right and left side with a distance from the skin surface of 15mm, with the deep tissue handpiece (spot size of 7.1cm²). In all the groups, millimetric facial measurements were taken from tragus to lateral commissure, and from lateral commissure to gonion in both sides.

Results: All differences between T1 and T6 were significant for the three groups, (paired T, P<0.05). The differences between the groups were generally not significant (P>0.05) except for commissure - right and left gonion when compared G1 vs CG (P<0.05) and G2 vs CG (P<0.05). Initial changes (T1-T2) between groups were significantly different except for the measurement from commissure to right tragus G1 vs CG (P=0.411) and from commissure to left tragus G2 vs CG (P=0.94). The faster resolution of the oedema occurred in G2 group. PTBM with an energy density of 68.33J/cm² was the most effective adjuvant to oral medication with non-steroidal anti-inflammatory, to decrease post-surgical oedema after mandibular orthognathic surgery.

J Strength Cond Res. 2018 Nov;32(11):3285-3293. doi: 10.1519/JSC.0000000000002339.

Time Response of Photobiomodulation Therapy on Muscular Fatigue in Humans

Mateus Rossato¹², Rodolfo A Dellagrana¹, Raphael L Sakugawa¹, Caetano D Lazzari¹, Bruno M Baroni³, Fernando Diefenthaeler¹

Abstract

Rossato, M, Dellagrana, RA, Sakugawa, RL, Lazzari, CD, Baroni, BM, and Diefenthaeler, F. Time response of photobiomodulation therapy on muscular fatigue in humans. J Strength Cond Res 32(11): 3285-3293, 2018-The aim of this study was to identify the effects of 2 different time responses on fatigue of knee extensor. Sixteen male volunteers (26 ± 6.0 years, 81 ± 12 kg, and 181 ± 7.4 cm) participated in the study. Participants performed the same protocol in 5 sessions {control, placebo (placebo applied both 6 hours before and immediately before the test), 6 hours before + immediately before (photobiomodulation therapy [PBMT] applied both 6 hours before and immediately before the test), 6 hours before (PBMT applied 6 hours before and placebo applied immediately before the test), and immediately before (placebo applied 6 hours before and PBMT applied immediately before the test)}. Photobiomodulation therapy was applied on knee extensor (9 sites; 30 J per site). Maximal isometric voluntary contraction (MIVC) was assessed before and after an isokinetic fatigue (45 flexion-extension concentric at 180°·s), associated with electromyography (root mean square [RMS] and median of frequency [MF]). For MIVC, there was no treatment × time interaction for all variables. Time effect was observed for peak torque (PT), RMS, and MF. Treatment effect was verified for PT, and 6 hours before + immediately before condition presented higher PT during MIVCpre than control (p = 0.004) and placebo (p = 0.044). The immediately before presented higher PT values than control (p = 0.047). Regarding MIVCpost, the PT for 6 hours before + immediately before presented higher values than control (p = 0.001) and placebo (p = 0.004). Peak torque during MIVC (pre to post) was reduced in 6 hours before + immediately before treatment (26%) compared with control (33%), placebo (29%), and immediately before (32%). The application of PBMT 6 hours + immediately before and immediately before exercise protocol is able to reduce the fatigue.

J Athl Train. 2013 Jan-Feb;48(1):57-67. doi: 10.4085/1062-6050-48.1.12.

Does phototherapy enhance skeletal muscle contractile function and postexercise recovery? A systematic review.

Borsa PA¹, Larkin KA, True JM.

Abstract

CONTEXT:

Recently, researchers have shown that phototherapy administered to skeletal muscle immediately before resistance exercise can enhance contractile function, prevent exercise-induced cell damage, and improve postexercise recovery of strength and function.

OBJECTIVE:

To critically evaluate original research addressing the ability of phototherapeutic devices, such as lasers and light-emitting diodes (LEDs), to enhance skeletal muscle contractile function, reduce exercise-induced muscle fatigue, and facilitate postexercise recovery.

DATA SOURCES:

We searched the electronic databases PubMed, SPORTDiscus, Web of Science, Scopus, and Rehabilitation & Physical Medicine without date limitations for the following key words: laser therapy, phototherapy, fatigue, exercise, circulation, microcirculation, and photobiomodulation.

STUDY SELECTION:

Eligible studies had to be original research published in English as full papers, involve human participants, and receive a minimum score of 7 out of 10 on the Physiotherapy Evidence Database (PEDro) scale.

DATA EXTRACTION:

Data of interest included elapsed time to fatigue, total number of repetitions to fatigue, total work performed, maximal voluntary isometric contraction (strength), electromyographic activity, and postexercise biomarker levels. We recorded the PEDro scores, beam characteristics, and treatment variables and calculated the therapeutic outcomes and effect sizes for the data sets.

DATA SYNTHESIS:

In total, 12 randomized controlled trials met the inclusion criteria. However, we excluded data from 2 studies, leaving 32 data sets from 10 studies. Twenty-four of the 32 data sets contained differences between active phototherapy and sham (placebo-control) treatment conditions for the various outcome measures. Exposing skeletal muscle to single-diode and multidiode laser or multidiode LED therapy was shown to positively affect physical performance by delaying the onset of fatigue, reducing the fatigue response, improving postexercise recovery, and protecting cells from exercise-induced damage.

CONCLUSIONS:

Phototherapy administered before resistance exercise consistently has been found to provide ergogenic and prophylactic benefits to skeletal muscle.

Lasers Med Sci. 2014 Nov;29(6):1967-76. doi: 10.1007/s10103-014-1611-7. Epub 2014 Jun 19.

Phototherapy in skeletal muscle performance and recovery after exercise: effect of combination of super-pulsed laser and light-emitting diodes.

Antonialli FC¹, De Marchi T, Tomazoni SS, Vanin AA, dos Santos Grandinetti V, de Paiva PR, Pinto HD, Miranda EF, de Tarso Camillo de Carvalho P, Leal-Junior EC.

Abstract

Recent studies with phototherapy have shown positive results in enhancement of performance and improvement of recovery when applied before exercise. However, several factors still remain unknown such as therapeutic windows, optimal treatment parameters, and effects of combination of different light sources (laser and LEDs). The aim of this study was to evaluate the effects of phototherapy with the combination of different light sources on skeletal muscle performance and post-exercise recovery, and to establish the optimal energy dose. A randomized, double-blinded, placebo-controlled trial with participation of 40 male healthy untrained volunteers was performed. A single phototherapy intervention was performed immediately after pre-exercise (baseline) maximum voluntary contraction (MVC) with a cluster of 12 diodes (4 of 905 nm lasers-0.3125 mW each, 4 of 875 nm LEDs-17.5 mW each, and 4 of 670 nm LEDs-15 mW each- manufactured by Multi Radiance Medical™) and dose of 10, 30, and 50 J or placebo in six sites of quadriceps. MVC, delayed onset muscle soreness (DOMS), and creatine kinase (CK) activity were analyzed. Assessments were performed before, 1 min, 1, 24, 48, 72, and 96 h after eccentric exercise protocol employed to induce fatigue. Phototherapy increased (p < 0.05) MVC was compared to placebo from immediately after to 96 h after exercise with 10 or 30 J doses (better results with 30 J dose). DOMS was significantly decreased compared to placebo (p < 0.05) with 30 J dose from 24 to 96 h after exercise, and with 50 J dose from immediately after to 96 h after exercise. CK activity was significantly decreased (p < 0.05) compared to placebo with all phototherapy doses from 1 to 96 h after exercise (except for 50 J dose at 96 h). Pre-exercise phototherapy with combination of low-level laser and LEDs, mainly with 30 J dose, significantly increases performance, decreases DOMS, and improves biochemical marker related to skeletal muscle damage.

Photomed Laser Surg. 2017 Nov;35(11):595-603. doi: 10.1089/pho.2017.4343.

Pre-Exercise Infrared Photobiomodulation Therapy (810 nm) in Skeletal Muscle Performance and Postexercise Recovery in Humans: What Is the Optimal Power Output?

de Oliveira AR^1,2, Vanin AA^1,3, Tomazoni SS⁴, Miranda EF¹, Albuquerque-Pontes GM^1,2, De Marchi T⁵, Dos Santos Grandinetti V², de Paiva PRV^1,3, Imperatori TBG¹, de Carvalho PTC^2,3, Bjordal JM⁶, Leal-Junior ECP^1,3.

Abstract

BACKGROUND:

Photobiomodulation therapy (PBMT) has recently been used to alleviate postexercise muscle fatigue and enhance recovery, demonstrating positive results. A previous study by our research group demonstrated the optimal dose for an infrared wavelength (810 nm), but the outcomes could be optimized further with the determination of the optimal output power.

OBJECTIVE:

The aim of the present study was to evaluate the effects of PBMT (through low-level laser therapy) on postexercise skeletal muscle recovery and identify the best output power.

MATERIALS AND METHODS:

A randomized, placebo-controlled double-blind clinical trial was conducted with the participation of 28 high-level soccer players. PBMT was applied before the eccentric contraction protocol with a cluster with five diodes, 810 nm, dose of 10 J, and output power of 100, 200, 400 mW per diode or placebo at six sites of knee extensors. Maximum isometric voluntary contraction (MIVC), delayed onset muscle soreness (DOMS) and biochemical markers related to muscle damage (creatine kinase and lactate dehydrogenase), inflammation (IL-1β, IL-6, and TNF-α), and oxidative stress (catalase, superoxide dismutase, carbonylated proteins, and thiobarbituric acid) were evaluated before isokinetic exercise, as well as at 1 min and at 1, 24, 48, 72, and 96 h, after the eccentric contraction protocol.

RESULTS:

PBMT increased MIVC and decreased DOMS and levels of biochemical markers (p < 0.05) with the power output of 100 and 200 mW, with better results for the power output of 100 mW.

CONCLUSIONS:

PBMT with 100 mW power output per diode (500 mW total) before exercise achieves best outcomes in enhancing muscular performance and postexercise recovery. Another time it has been demonstrated that more power output is not necessarily better.

J Athl Train. 2015 Jan;50(1):45-50. doi: 10.4085/1062-6050-49.3.82. Epub 2014 Nov 14.

Near-infrared light therapy to attenuate strength loss after strenuous resistance exercise.

Larkin-Kaiser KA¹, Christou E, Tillman M, George S, Borsa PA.

Abstract

CONTEXT:

Near-infrared (NIR) light therapy is purported to act as an ergogenic aid by enhancing the contractile function of skeletal muscle. Improving muscle function is a new avenue for research in the area of laser therapy; however, very few researchers have examined the ergogenic effects of NIR light therapy and the influence it may have on the recovery process during rehabilitation.

OBJECTIVE:

To evaluate the ergogenic effect of NIR light therapy on skeletal muscle function.

DESIGN:

Crossover study.

SETTING:

Controlled laboratory.

PATIENTS OR OTHER PARTICIPANTS:

Thirty-nine healthy men (n = 21) and women (n = 18; age = 20.0 ± 0.2 years, height = 169 ± 2 cm, mass = 68.4 ± 1.8 kg, body mass index = 23.8 ± 0.4 kg/m(2)).

INTERVENTION(S):

Each participant received active and sham treatments on the biceps brachii muscle on 2 separate days. The order of treatment was randomized. A class 4 laser with a cumulative dose of 360 J was used for the active treatment. After receiving the treatment on each day, participants completed an elbow-flexion resistance-exercise protocol.

MAIN OUTCOME MEASURE(S):

The dependent variables were elbow range of motion, muscle point tenderness, and strength (peak torque). Analysis of variance with repeated measures was used to assess changes in these measures between treatments at baseline and at follow-up, 48 hours postexercise. Additionally, immediate strength loss postexercise was compared between treatments using a paired t test.

RESULTS:

Preexercise to postexercise strength loss for the active laser treatment, although small, was less than with the sham treatment (P = .05).

CONCLUSIONS:

Applied to skeletal muscle before resistance exercise, IR light therapy effectively attenuated strength loss. Therefore, NIR light therapy may be a beneficial, noninvasive modality for improving muscle function during rehabilitation after musculoskeletal injury. However, future studies using higher treatment doses are warranted.

J Sport Rehabil. 2020 May 5:1-4. doi: 10.1123/jsr.2019-0421. [Epub ahead of print]

Does Low-Level Laser Therapy Decrease Muscle-Damaging Mediators After Performance in Soccer Athletes Versus Sham Laser Treatment? A Critically Appraised Topic.

Bettleyon J, Kaminski TW.

Abstract

Clinical Scenario: Low-level laser therapy (LLLT) is a controversial topic for its use in athletic recovery, mainly due to inconsistency in research regarding the application of LLLT. Articles on LLLT have assessed its effectiveness in untrained humans through pain scales, functional scales, and blood draws, and it has been found capable in nonathletic rehabilitative use. The controversy lies with LLLT in the recovering athlete. Not only do athletes need to perform at high levels, but each sport is unique in the metabolic demands placed on the athletes' bodies. This modality can alter chemical mediators of the inflammatory process, specifically blood lactate (BL) and creatine kinase (CK). During soccer contests, it is a common problem for athletes to have an average CK level of 800 U/L and BL of 8 mmol·L, increasing delayed-onset muscle soreness and fatigue. Micro-CK level elevation is associated with cellular membrane damage, localized hypoxia, and electrolyte imbalances, hindering the recovery process. Clinical Question: Does LLLT decrease muscle-damaging mediators effecting player fatigue and delayed-onset muscle soreness after performance in soccer athletes versus sham treatment? Summary of Key Findings: In 3 studies, preperformance, postperformance, or preperformance and postperformance LLLT was performed and evaluated BL (2 of 3) and CK (2 of 3). In each article, BL and CK showed a significant decrease (P < .05) when performed either preperformance or postperformance versus the control group. The greatest decrease in these mediators was noticed when postperformance laser therapy was performed. Clinical Bottom Line: LLLT at 10, 30, or 50 J performed at a minimum of 2 locations on the rectus femoris, vastus lateralis, and vastus medialis bilaterally for 10 seconds each is significant in decreasing blood serum levels of BL and CK when performed postexercise. Strength of Recommendations: All 3 articles obtained a Physiotherapy Evidence Database score of ≥8/10.

J Sport Rehabil. 2019 Jul 1;28(5):526-531. doi: 10.1123/jsr.2017-0359. Epub 2019 Jan 29.

The Effectiveness of Photobiomodulation Therapy Versus Cryotherapy for Skeletal Muscle Recovery: A Critically Appraised Topic.

Fisher SR, Rigby JH, Mettler JA, McCurdy KW.

Abstract

Clinical Scenario: Cryotherapy is one of the most commonly used modalities for postexercise muscle recovery despite inconsistencies in the literature validating its effectiveness. With the need to find a more effective modality, photobiomodulation therapy (PBMT) has gained popularity because of recent research demonstrating its ability to accelerate the muscle recovery process. Focused Clinical Question: Is PBMT more effective than cryotherapy at reducing recovery time and decreasing delayed onset muscle soreness after strenuous exercise? Summary of Key Findings: Three moderate- to high-quality double-blinded, randomized, placebo-controlled trials and 2 low- to moderate-quality translational studies performed on rats were included in this critically appraised topic. All 5 studies supported the use of PBMT over cryotherapy as a treatment for postexercise muscle recovery following exercise. PBMT was superior in reducing creatine kinase, inflammation markers, and blood lactate compared with cryotherapy, following strenuous/high intensity aerobic or strength muscular exercise. PBMT was also shown to improve postexercise muscle performance and function more than cryotherapy. Clinical Bottom Line: There is moderate evidence to suggest the use of PBMT over cryotherapy postexercise to enhance muscle recovery in trained and untrained athletes. Shorter recovery times and increased muscle performance can be seen 24 to 96 hours following PBMT application. Strength of Recommendation: Based on consistent findings from all 5 studies, there is grade B evidence to support the use of PBMT over cryotherapy for more effective postexercise recovery of skeletal muscle performance.

J Athl Train. 2013 Jan-Feb;48(1):57-67. doi: 10.4085/1062-6050-48.1.12.

Does phototherapy enhance skeletal muscle contractile function and postexercise recovery? A systematic review.

Borsa PA¹, Larkin KA, True JM.

Abstract

CONTEXT:

OBJECTIVE:

DATA SOURCES:

STUDY SELECTION:

DATA EXTRACTION:

DATA SYNTHESIS:

CONCLUSIONS:

Phototherapy administered before resistance exercise consistently has been found to provide ergogenic and prophylactic benefits to skeletal muscle.

Lasers Med Sci. 2014 Nov;29(6):1967-76. doi: 10.1007/s10103-014-1611-7. Epub 2014 Jun 19.

Phototherapy in skeletal muscle performance and recovery after exercise: effect of combination of super-pulsed laser and light-emitting diodes.

Antonialli FC¹, De Marchi T, Tomazoni SS, Vanin AA, dos Santos Grandinetti V, de Paiva PR, Pinto HD, Miranda EF, de Tarso Camillo de Carvalho P, Leal-Junior EC.

Abstract

J Biophotonics. 2016 Dec; 9(11-12): 1273-1299

Photobiomodulation in human muscle tissue: an advantage in sports performance?

Cleber Ferraresi, Ying-Ying Huang, and Michael R. Hamblin

Abstract

Photobiomodulation (PBM) describes the use of red or near-infrared (NIR) light to vstimulate, heal, and regenerate damaged tissue. Both pre-conditioning (light delivered to muscles before exercise) and PBM applied after exercise can increase sports performance in athletes. This review covers the effects of PBM on human muscle tissue in clinical trials in volunteers related to sports performance and in athletes. The parameters used were categorized into those with positive effects or no effects on muscle performance and recovery. Randomized controlled trials and case-control studies in both healthy trained and untrained participants, and elite athletes were retrieved from MEDLINE up to 2016. Performance metrics included fatigue, number of repetitions, torque, hypertrophy; measures of muscle damage and recovery such as creatine kinase and delayed onset muscle soreness. Searches retrieved 533 studies, of which 46 were included in the review (n=1045 participants). Studies used single laser probes, cluster of laser-diodes, LED-clusters, mixed clusters (lasers and LEDs), and flexible LED arrays. Both red, NIR, and red/NIR mixtures were used. PBM can increase muscle mass gained after training, and decrease inflammation and oxidative stress in muscle biopsies. We raise the question of whether PBM should be permitted in athletic competition by international regulatory authorities.

Disclaimer: The above research articles are for information purposes only and PainBuster®LLC and PainBuster nor its affiliates make no claims of any actual proven therapeutic benefits to the details in these research studies besides the FDA approved indications of use for the PainBuster device.