PainSci commentary on Sikdar 2008: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
Ultrasound elastography measures tissue stiffness by vibrating tissues with sound waves and measuring the differences — stiff tissue vibrates more slowly. If a trigger point is associated contracted muscle tissue, this method should show it.
In the first of a series of related studies, Sidkar et al. used USE on two healthy men and women with palpable trapezius trigger points that were not actively causing symptoms — “latent” trigger points. USE clearly showed areas of stiff tissue in the same location as palpable trigger points, but did not show the same thing in healthy tissue.
Three more studies by the same group have shown similar results since, studying more people in more detail: see , Sikdar 2009, Ballyns 2011, Turo 2013.
~ Paul Ingraham
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Myofascial trigger points (MTrPs) are palpable hyperirritable nodules in skeletal muscle that are associated with chronic musculoskeletal pain. The goal of this study was to image MTrPs in the upper trapezius muscle using 2D gray scale ultrasound (US) and vibration sonoelastography (VSE) for differentiating the soft tissue characteristics of MTrPs compared to surrounding muscle. MTrPs appeared as hypoechoeic elliptically-shaped focal regions within the trapezius muscle on 2D US. Audio-frequency vibrations (100-250 Hz) were induced in the trapezius muscle of four volunteers with clinically identifiable MTrPs, and the induced vibration amplitudes were imaged using the color Doppler variance mode, and were further quantified using spectral Doppler analysis. Spectral Doppler analysis showed that vibration amplitudes were 27% lower on average within the MTrP compared to surrounding tissue (p0.05). Color variance imaging consistently detected a focal region of reduced vibration amplitude, which correlated with the hypoechoeic region identified as an MTrP (r =0.76 for area). Real-time 2D US identifies MTrPs, and VSE is feasible for differentiating MTrPs from surrounding tissue. Preliminary findings show that MTrPs are hypoechoeic on 2D US and the relative stiffness of MTrPs can be quantified using VSE. Ultrasound offers a convenient, accessible and low-risk approach for identifying MTrPs and for evaluating clinical observations of palpable, painful nodules.
- “Novel applications of ultrasound technology to visualize and characterize myofascial trigger points and surrounding soft tissue,” Siddhartha Sikdar, Jay P Shah, Tadesse Gebreab, Ru-Huey Yen, Elizabeth Gilliams, Jerome Danoff, and Lynn H Gerber, Archives of Physical Medicine & Rehabilitation, 2009.
- “Objective sonographic measures for characterizing myofascial trigger points associated with cervical pain,” Jeffrey J Ballyns, Jay P Shah, Jennifer Hammond, Tadesse Gebreab, Lynn H Gerber, and Siddhartha Sikdar, J Ultrasound Med, 2011.
- “Ultrasonic characterization of the upper trapezius muscle in patients with chronic neck pain,” Diego Turo, Paul Otto, Jay P Shah, Juliana Heimur, Tadesse Gebreab, Maryam Zaazhoa, Katherine Armstrong, Lynn H Gerber, and Siddhartha Sikdar, Ultrason Imaging, 2013.
- “Microscopic features and transient contraction of palpable bands in canine muscle,” D G Simons and W C Stolov, Am J Phys Med, 1976.
- “Endplate potentials are common to midfiber myofacial trigger points,” David G Simons, Chang-Zern Hong, and Lois Statham Simons, Am J Phys Med Rehabil, 2002.
- “Accelerated muscle fatigability of latent myofascial trigger points in humans,” Hong-You Ge, Lars Arendt-Nielsen, and Pascal Madeleine, Pain Med, 2012.
- “Two-dimensional ultrasound and ultrasound elastography imaging of trigger points in women with myofascial pain syndrome treated by acupuncture and electroacupuncture: a double-blinded randomized controlled pilot study,” Cristina Emöke Erika Müller, Maria Fernanda Montans Aranha, and Maria Beatriz Duarte Gavião, Ultrason Imaging, 2015.
- “Induction of muscle cramps by nociceptive stimulation of latent myofascial trigger points,” Hong-You Ge, Yang Zhang, Shellie Boudreau, Shou-Wei Yue, and Lars Arendt-Nielsen, Exp Brain Res, 2008.
- “Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: an application of muscle pain concepts to myofascial pain syndrome,” Jay P Shah and Elizabeth A Gilliams, Journal of Bodywork & Movement Therapies, 2008.
- “Ability of magnetic resonance elastography to assess taut bands,” Qingshan Chen, Jeffrey Basford, and Kai-Nan An, Clin Biomech (Bristol, Avon), 2008.
- “Identification and quantification of myofascial taut bands with magnetic resonance elastography,” Qingshan Chen, Sabine Bensamoun, Jeffrey R Basford, Jeffrey M Thompson, and Kai-Nan An, Archives of Physical Medicine & Rehabilitation, 2007.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Exercise and education versus saline injections for knee osteoarthritis: a randomised controlled equivalence trial. Bandak 2022 Ann Rheum Dis.
- Association of Lumbar MRI Findings with Current and Future Back Pain in a Population-based Cohort Study. Kasch 2022 Spine (Phila Pa 1976).
- A double-blinded randomised controlled study of the value of sequential intravenous and oral magnesium therapy in patients with chronic low back pain with a neuropathic component. Yousef 2013 Anaesthesia.
- Is Neck Posture Subgroup in Late Adolescence a Risk Factor for Persistent Neck Pain in Young Adults? A Prospective Study. Richards 2021 Phys Ther.
- Sudden amnesia resulting in pain relief: the relationship between memory and pain. Choi 2007 Pain.