Journal of Pain Research (May 2021)
Potential Role of MRI Imaging for Myofascial Pain: A Scoping Review for the Clinicians and Theoretical Considerations
Abstract
Valerie Evans,1,2 Michael Behr,2,3 Anshika Gangwar,2 Michael D Noseworthy,4 Dinesh Kumbhare1– 3 1Institute of Biomaterials and Biomedical Engineering (IBBME), University of Toronto, Toronto, Ontario, Canada; 2University Health Network – Toronto Rehabilitation Institute, Toronto, Ontario, Canada; 3Department of Medicine, Division of Physical Medicine and Rehabilitation, University of Toronto, Toronto, Ontario, Canada; 4Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, CanadaCorrespondence: Dinesh KumbhareDepartment of Medicine and IBBME, University of Toronto, 550 University Ave, Suite 7-131, Toronto, ON, M5G 2A2, CanadaTel +1 416-597-3422 x 4612Email [email protected]: The most common cause of chronic musculoskeletal pain is chronic myofascial pain syndrome (MPS). MPS often presents with increased muscle stiffness, and the myofascial trigger point (MTrP). Imaging modalities have been used to identify the MTrP, but their role in the detection and diagnosis of MPS remains unclear. The purpose of this review was to identify evidence in literature for the use of imaging in the role of classifying and explaining the physiology of MTrPs. Since few imaging techniques have been performed on MTrPs, we explored the imaging techniques that can effectively image complex skeletal muscle microstructure, and how they could be used. As part of a scoping review, we conducted a systematic search from three medical databases (CINAHL, EMBASE and MEDLINE) from year to year to analyze past MTrP imaging, as well as analyzing imaging techniques performed on the microstructure of muscle. Previously, ultrasound has been used to differentiate active, latent MTrPs, but these studies do not adequately address their underlying anatomical structure. MRI remains the standard method of imaging skeletal muscle. The existing MRI literature suggests that the DTI technique can quantify muscle injury, strain, and structure. However, theoretically, HARDI and DKI techniques seem to provide more information for complex structural areas, although these modalities have a disadvantage of longer scan times and have not been widely used on skeletal muscle. Our review suggests that DTI is the most effective imaging modality that has been used to define the microstructure of muscle and hence, could be optimal to image the MTrP. HARDI and DKI are techniques with theoretical potential for analysis of muscle, which may provide more detailed information representative of finer muscle structural features. Future research utilizing MRI techniques to image muscle are necessary to provide a more robust means of imaging skeletal muscle and the MTrP.Keywords: myofascial pain syndrome, MRI, trigger points, chronic pain, imaging
