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.
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- “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.
- “Assessment of myofascial trigger points (MTrPs): a new application of ultrasound imaging and vibration sonoelastography,” Siddhartha Sikdar, Jay P Shah, Elizabeth Gilliams, Tadesse Gebreab, and Lynn H Gerber, Conf Proc IEEE Eng Med Biol Soc, 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.
Specifically regarding Shah 2008:
- PS Toxic Muscle Knots — Research suggests myofascial trigger points may be quagmires of irritating molecules
Shah 2008 is about: