Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: an application of muscle pain concepts to myofascial pain syndrome
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.
This article discusses muscle pain concepts in the context of myofascial pain syndrome (MPS) and summarizes microdialysis studies that have surveyed the biochemical basis of this musculoskeletal pain condition. Though MPS is a common type of non-articular pain, its pathophysiology is only beginning to be understood due to its enormous complexity. MPS is characterized by the presence of myofascial trigger points (MTrPs), which are defined as hyperirritable nodules located within a taut band of skeletal muscle. MTrPs may be active (spontaneously painful and symptomatic) or latent (non-spontaneously painful). Painful MTrPs activate muscle nociceptors that, upon sustained noxious stimulation, initiate motor and sensory changes in the peripheral and central nervous systems. This process is called sensitization. In order to investigate the peripheral factors that influence the sensitization process, a microdialysis technique was developed to quantitatively measure the biochemical milieu of skeletal muscle. Biochemical differences were found between active and latent MTrPs, as well as in comparison with healthy muscle tissue. In this paper we relate the findings of elevated levels of sensitizing substances within painful muscle to the current theoretical framework of muscle pain and MTrP development.
related content
- “Microscopic features and transient contraction of palpable bands in canine muscle,” Simons et al, Am J Phys Med, 1976.
- “Endplate potentials are common to midfiber myofacial trigger points,” Simons et al, Am J Phys Med Rehabil, 2002.
- “Accelerated muscle fatigability of latent myofascial trigger points in humans,” Ge et al, 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,” Müller et al, Ultrason Imaging, 2015.
- “Induction of muscle cramps by nociceptive stimulation of latent myofascial trigger points,” Ge et al, Exp Brain Res, 2008.
- “Assessment of myofascial trigger points (MTrPs): a new application of ultrasound imaging and vibration sonoelastography,” Sikdar et al, Conf Proc IEEE Eng Med Biol Soc, 2008.
- “Ability of magnetic resonance elastography to assess taut bands,” Chen et al, Clin Biomech (Bristol, Avon), 2008.
- “Identification and quantification of myofascial taut bands with magnetic resonance elastography,” Chen et al, Archives of Physical Medicine & Rehabilitation, 2007.
Specifically regarding Shah 2008:
- Toxic Muscle Knots — Research suggests myofascial trigger points may be quagmires of irritating molecules
Shah 2008 is about:
- “Biochemicals associated with pain and inflammation are elevated in sites near to and remote from active myofascial trigger points,” Shah et al, Archives of Physical Medicine & Rehabilitation, 2008.
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:
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- Gabapentinoids and Risk of Hip Fracture. Leung 2024 JAMA Netw Open.