Effectiveness of high-intensity laser therapy added to a physical therapy program for the treatment of myofascial pain syndrome - a systematic review and meta-analysis

High-intensity laser therapy (HILT) has been incorporated last years as a new resource for musculoskeletal pain management, although studies that support it in Myofascial pain syndrome (MFPS) are limited. This systematic review (SR) aimed to determine the effectiveness of HILT as a therapeutic resource for myofascial pain management. Randomized clinical trials (RCTs) were searched in PubMed, Web of Science, Scopus, Cinahl, Science Direct, and PEDro databases on April 30,2022. The selection criteria included RCTs that compared HILT added to a physical therapy program to a program without HILT, considering as the main outcome pain reduction and secondary results improvement in range of motion or disability in adults with MFPS. Three studies met the eligibility criteria and were included for analysis. The risk of bias was assessed using the Cochrane Rob2 tool, and a meta-analysis was conducted removing one low-quality study. RCTs reported a pain decrease for HILT (p < 0.01), and the meta-analysis revealed a mean difference of –1.90 cm (CI 95% = -2.58,-1.22) for the visual analog scale (0–10 cm) after four weeks, with a pooled effect in favor of HILT (p < 0.01). Although the RCTs individually document improvements in range of motion (ROM) (p < 0.05). RCTs show that HILT is effective in reducing pain but not in improving the range of motion in MFPS patients. However, even though the combined analgesic effect is significant, it would not have sufficient clinical relevance. The development of new RCTs is suggested to confirm or improve these results.