Myofascial pain is a common musculoskeletal condition characterized by myofascial trigger points, functional limitations, and reduced quality of life. Therapeutic ultrasound (TUS) is frequently used in physiotherapy management, yet its effects remain controversial. This systematic review aims to evaluate the effects of TUS compared with placebo, other physical modalities, or conventional treatment in individuals with myofascial pain syndrome, focusing on outcomes of pain, function, and range of motion. This systematic review followed PRISMA 2020 guidelines. Searches were conducted in PubMed, PEDro, CENTRAL, LILACS, and Google Scholar. Eligible studies were randomized controlled trials or quasi-experimental studies comparing TUS to placebo, exercise, other physical modalities, or conventional treatment. Outcomes included pain, function, range of motion, and sensitivity. Risk of bias was assessed using the Cochrane RoB-2 tool. Eight studies were included. Ultrasound was superior to placebo for pain, pressure pain threshold, and function. It demonstrated comparable efficacy to lidocaine injection and other physical modalities. Benefits were observed for trapezius and masticatory muscles across pain, pressure pain threshold, cervical range of motion, and disability outcomes. No serious adverse effects were reported. Methodological quality varied, with only two studies showing low risk of bias; heterogeneity in parameters and co-interventions precluded meta-analysis. TUS appears to be a safe intervention for myofascial pain syndrome, with preliminary evidence of benefits for pain, pressure pain threshold, and function in the trapezius and masticatory muscles. However, given the methodological heterogeneity, limited number of studies, and risk of publication bias, these findings should be interpreted cautiously. Further high-quality trials are needed before firm clinical recommendations can be made.

INTRODUCTION
MATERIALS AND METHODS
    1. Search Strategies
    2. Eligibility Criteria
    3. Selection of Studies
    4. Data Collected
    5. Outcome Measures
    6. Individual Assessment of Risk of Bias in Studies
RESULTS
    1. Presentation of Individual Studies
    2. Outcomes
    3. Security
    4. Manuscript Quality Review
DISCUSSION
FUNDING
ACKNOWLEDGEMENTS
CONFLICTS OF INTEREST
AUTHOR CONTRIBUTIONS
ORCID
REFERENCES

• Andressa Camilli Iurczaki(Department of Physical Therapy, Western Paraná State University (UNIOESTE), Cascavel, Paraná)
• Daniela Fátima Grosso(Department of Physical Therapy, Western Paraná State University (UNIOESTE), Cascavel, Paraná)
• Thainá Flyssak Piloneto(Department of Physical Therapy, Western Paraná State University (UNIOESTE), Cascavel, Paraná)
• Márcia Rosângela Buzanello(Department of Physical Therapy, Western Paraná State University (UNIOESTE), Cascavel, Paraná)
• Gladson Ricardo Flor Bertolini(Department of Physical Therapy, Western Paraná State University (UNIOESTE), Cascavel, Paraná) Corresponding author
• Dérrick Patrick Artioli(Center for Biological and Health Sciences, Lusíadas University Center (UNILUS), Santos, São Paulo, Brazil)