The Effectiveness of the Polarized Low-Level Laser in the Treatment of Patients With Myofascial Trigger Points in the Trapezius Muscles

Abstract

Introduction: This study assessed the effect of polarized low-level laser therapy (PLLLT) on the treatment of myofascial trigger points (MTrPs) in the trapezius muscles. Its effectiveness in pain reduction was compared to low-level laser therapy (LLLT). Methods: Sixty-four patients with MTrPs were randomly divided into 2 groups, namely PLLLT and LLLT. Each patient received treatment for a period of 2 weeks, 5 sessions a week. The intensity of laser irradiation to the skin surface was 6 J/cm 2 . The system exit power was 160 mw at a 755 nm wavelength. The visual analog scale (VAS) for the 1st, 5th and 10th sessions was analyzed through two-way repeated measures ANOVA. Results: Increasing the number of treatment sessions was effective in reducing pain intensity (P > 0.05). The effect of LLLT on pain reduction was significantly greater than that of PLLLT (P > 0.05). Referred pain (RP), the limitation of neck movement (LNM), the presence of muscular taut band (PMTB) and the sensitivity of muscular taut band (SMTB) were reduced significantly by the end of the 10th session, compared with participants' condition at the beginning of the 1st session in both groups. Conclusion: PLLLT and LLLT can effectively treat MTrPs in the trapezius muscles and they reduce RP, LNM, PMTB, and SMTB in particular. However, the effect of the LLLT was significantly greater than that of PLLLT. In accordance with the observed results, LLLT is recommended as an effective method for treating MTrPs.

Comparison of the Effects of Dry Needling and Low-Level Laser on the Latent Trigger Points of Upper Trapezius

“…They found that both techniques effectively treat MTrPs and reduce pain, limitation of neck movement, and PPT. However, the effect of the LLLT was more significant in comparison to the PLLLT (52). Waseem et al (2020) in their study found that the combination of conventional physical therapy and LLLT was more effective than conventional physical therapy alone on PPT and CROM in patients with a trigger point in their UT muscle (53).…”

“…Results of some of the previous research are in line with those of this study in terms of the efficacy of LLLT on the decrease of symptoms of MTrPs. Shahimoridi et al (2020) compared the effects of LLLT and polarized low-level laser therapy (PLLT) on the treatment of MTrPs in the trapezius muscle. They found that both techniques effectively treat MTrPs and reduce pain, limitation of neck movement, and PPT.…”

Immediate Evaluation of the Effect of Infrared LED Photobiomodulation on Childhood Sleep Bruxism: A Randomized Clinical Trial

“…The application of LED to the masticatory muscles affects the local tissues around the light application site and previous studies have shown the effectiveness of LED treatment in muscle tissues [ 26 , 27 , 28 ]. The literature also reports that it is possible to observe systemic responses through light therapy, with the action of deep light stimulation directly on the brain [ 29 ].…”

Acute Effects of Tecar Therapy on Skin Temperature, Ankle Mobility and Hyperalgesia in Myofascial Pain Syndrome in Professional Basketball Players: A Pilot Study

“…Contrary to our results, other similar treatments were effective in reducing mechanical hyperalgesia compared to control groups. The main difference was that the technique was applied on active MTPs rather than on latent MTPs [50]. Despite this clinical difference, an increase in generalized hyperalgesia pressure can be found in asymptomatic participants with latent MTPs [51], and their treatment may reduce latent MTP hyperalgesia.…”