PhotoBioModulation And Pain
PhotoBioModulation And Pain
PhotoBioModulation And Pain
Low Level Light Therapy for chronic knee joint pain patients
Low Level Light Therapy for chronic
knee joint pain patients
★ Key Take-Aways
Key Take-Aways:
⮕ After end of the treatment regimen a significant improvement was observed
⮕ No significant differences were observed in the knee joint range of motion
Authors
Takashi Nakamura, Satoru Ebihara, Ikuko Ohkuni, Hideaki Izukura, Takashi Harada, Nobuyuki Ushigome, Toshio Ohshiro, Yoshiro Musha, Hiroshi Takahashi, Kazuaki Tsuchiya, Ayako Kubota
Abstract
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 semiconductor laser device was used to deliver 20.1 J/cm(2) 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.
Massachusetts General Hospital | 2020
Photobiomodulation Therapy in the Treatment of Pain And Inflammation:
A Literature Review
Photobiomodulation Therapy in the Treatment of Pain And Inflammation: A Literature Review
Photobiomodulation Therapy in the Treatment of Pain And Inflammation:
A Literature Review
★ Key Take-Aways ⮕
Key Take-Aways:
⮕ The studies confirm the positive effects that this therapy has on proinflammatory biomarkers
⮕ Quality of the studies collected on the application of PBM in the treatment of inflammation and chronic pain is generally high, so they have excellent quality in terms of methodology
⮕ The studies confirm the positive effects that this therapy has on proinflammatory biomarkers
⮕ Quality of the studies collected on the application of PBM in the treatment of inflammation and chronic pain is generally high, so they have excellent quality in terms of methodology
Authors
Ana González-Muñoz, María Cuevas-Cervera, José Javier Pérez-Montilla, Daniel Aguilar-Núñez, Dina Hamed-Hamed, María Aguilar-García, Leo Pruimboom, Santiago Navarro-Ledesma | Editor: George A Koumantakis
Abstract
Photobiomodulation therapy (PBM) commonly uses wavelengths of light with an energy density ranging from 1 to 150 J/cm2 and from 600 to 1070 nm. The effective tissue penetration is maximal in this range with hemoglobin and melanin, as the principal tissue chromophores, having high absorption bands at wavelengths shorter than 600 nm. The treatment of superficial tissue uses wavelengths in the range of 600 to 700 nm, while the treatment of deeper tissue uses wavelengths in the range of 780 to 950 nm [1,2].
Currently, whole-body PBM has shown a systemic response in addition to the local response, with improvements in quality of life, pain, sleep disorders, tiredness, muscle spasm, morning stiffness, psychological factors, elastic properties of tissue, circadian rhythms, tender points, and in fibromyalgia sufferers [3,4,5,6,7].
Furthermore, PBM therapy has also been shown to improve cerebral blood flow, neuronal bioenergetic functions, neuroinflammation, oxidative stress, neural apoptosis, neurogenesis, and neurotrophic factors, and additionally has effects on intrinsic brain networks [1].
In addition, PBM is also thought to affect the secretion of certain hormones, such as serotonin and endorphins, leading to a reduction in pain signaling [8].
Chronic pain is a problem that has a very notorious impact on society and people’s lives and is one of the most common health problems among older adults (>65 years). It is estimated that 13–50% of adults in the United Kingdom suffer from chronic pain although it is difficult to obtain accurate data since the estimates for the prevalence in the population vary greatly by place, time, and
population. It has been estimated to be 8% per year in the UK.
On the other hand, the US sets its estimated costs attributable to chronic pain, including disability, loss of work, and treatments, at about USD 600 million annually, with an incidence of 28.4% in the adult population. Treatment in these older adults is complex since it must have a multifactorial focus that includes pharmacological interventions, physical rehabilitation, and procedures to eradicate the cycle of pain [9,10,11,12]. By definition, chronic pain is pain that persists for at least 3 months. It is a factor in premature death and accelerated cognitive deterioration. In turn, this deterioration and dementia make treatment decisions difficult since the patient’s ability to perceive pain and report it is impaired [11].
PMC | PubMed Central | 2023 | PMCID: PMC10094541 | PMID: 37046865
Mechanisms, location, and
repeatability quantified by pain threshold
& neural biomarkers in mice
★ Key Take-Aways ⮕
⮕ Data suggest that PBM to the DRG could be tested in human patients with chronic peripheral pain
⮕ The wider analgesic applications of PBM should also be further explored. It would be clinically feasible for instance, to deliver PBM to the back or head of patients who are about to undergo a painful procedure
Authors
Marcelo Victor Pires de Sousa, Masayoshi Kawakubo, Cleber Ferraresi, Beatriz Kaippert, Elisabeth Mateus Yoshimura, and Michael R. Hamblin
Abstract
In the present study, the pain threshold in the right hind-paw of mice was studied, after PBM (810 nm CW laser, spot size 1 cm or 6 cm , 1.2–36 J/cm ) applied to various anatomical locations. The pain threshold, measured with von Frey filaments, was increased more than 3-fold by PBM to the lower back (dorsal root ganglion, DRG), as well as to other neural structures along the pathway such as the head, neck and ipsilateral (right) paw.
On the other hand, application of PBM to the contralateral (left) paw, abdomen and tail had no effect. The optimal effect occurred 2–3 hours post-PBM and disappeared by 24 hours. Seven daily irradiations showed no development of tolerance.
Type 1 metabotropic glutamate receptors decreased, and prostatic acid phosphatase and tubulinpositive varicosities were increased as shown by immunofluorescence of DRG samples. These findings elucidate the mechanisms of PBM for pain and provide insights for clinical practice.
1. INTRODUCTION
Throughout the world, injuries, diseases and a variety of chronic or degenerative conditions affect billions of people with acute and/or chronic pain [1]. Better therapies are required for painful conditions such as degenerative orthopedic conditions, neuropathic pain, and chronic central pain. In general, pharmaceutical therapies (painkillers) decrease the intensity and severity of the symptoms but have many undesired side-effects [2]. Moreover, long-term treatment tends to decrease effectiveness as the subject develops drug tolerance [3].
There has recently been an epidemic of opiate overdose-induced deaths, many of which were in individuals originally prescribed opiates for chronic pain [4].
Photobiomodulation therapy (PBMT) also known as low-level laser/light therapy (LLLT), is a rapidly growing approach to stimulate healing [5, 6], increase tissue regeneration [6] and reduce pain [7] and inflammation [8]. PBMT has no known side-effects, and as yet has shown no long-term adaptation to the treatment [9, 10].
Typically, PBMT uses exposure of tissues to low-intensity light (power densities in the region of 1–100 mW/cm ) for a few minutes [9]. The wavelengths employed are mostly in the red or near-infrared (NIR) spectral regions, and although lasers were originally used exclusively, in recent years light emitting diodes (LED) have become popular [11]. During this exposure, light is absorbed by molecules in the cells called chromophores, such as cytochrome-c-oxidase, located inside mitochondria. Light absorption induces changes in cell signaling pathways and activation of transcription factors.
Application of NIR light for pain has clinical advantages such as deeper penetration, which allows noninvasive, transcutaneous
delivery [12]. Reports of adverse events in PBMT are extremely rare or non-existent, and this therapy has been approved by FDA (and other national health agencies around the world) for various indications [11].
Over the past decades, much PBM research has focused on demonstrating efficacy in animal models of potentially painful conditions. We previously reported [6] that PBM (810 nm laser, 300 mW/cm , 7.2 or 36 J/cm ) delivered to the head of mice could decrease the reaction to a potentially painful stimulus in the foot, evoked either by light pressure (von Frey filaments), cold plate, or inflammation (formalin injection), or in the tail (evoked by heat). Therefore, the goals of the present study were to establish a reliable treatment regimen (optimum bodily location of irradiation, and the optimum dose or energy density) and to investigate the mechanisms of action underlying the effect of light on pain threshold. The time of onset, duration, and repeatability of the procedure were investigated. This study also aimed to investigate the effects of PBM on neurological markers (mGluR1 and PAP) involved in pain signaling in the peripheral nervous system (the dorsal root ganglia, DRG).
PMC | PubMed Central | 2023 | PMCID: PMC6037550 | NIHMSID: NIHMS946841 | PMID: 29484823