Assessment of Myofascial Trigger Points via Imaging: A Systematic Review.

ABSTRACT This study systematically reviewed the published literature on the objective characterization of myofascial pain syndrome and myofascial trigger points using imaging methods. PubMed, Embase, Ovid and the Cochrane Library databases were utilized, while citation searching was conducted in Scopus. Citations were restricted to those published in English and in peer-reviewed journals between 2000-2021. Out of 1,762 abstracts screened, 69 articles underwent full-text review and 33 were included. Imaging data assessing myofascial trigger points (MTrPs) or myofascial pain syndrome (MPS) were extracted and important qualitative and quantitative information on general study methodologies, study populations, sample sizes, and MTrP/MPS evaluation were tabulated. Methodological quality of eligible studies was assessed based on the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria. Biomechanical properties and blood flow of active and latent MTrPs assessed via imaging were found to be quantifiably distinct from those of healthy tissue. While these studies show promise, more studies are needed. Future studies should focus on assessing diagnostic test accuracy and testing the reproducibility of results to establish the best performing methods. Increasing methodological consistency would further motivate implementing imaging methods in larger clinical studies. Considering the evidence on efficacy, cost, ease of use and time constraints, US-based methods are currently the imaging modalities of choice for MPS/MTrP assessment.