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Updated: Aug 13, 2026
07:16
Extraction of the EPP Component from the Surface EMG
Published on: December 16, 2009
Endplate potentials are common to midfiber myofacial trigger points
David G Simons1, Chang-Zern Hong, Lois Statham Simons
1Department of Physical Medicine and Rehabilitation, University of California-Irvine, USA.
Summary
Endplate noise, a potential biomarker for myofascial trigger points (MTrPs), was more common in MTrPs than other muscle zones. This finding suggests endplate noise is characteristic but not exclusive to MTrPs.
Area of Science:
- Neuromuscular physiology
- Skeletal muscle research
- Pain medicine
Background:
- Myofascial trigger points (MTrPs) are associated with distinct electrical phenomena.
- Endplate potentials, including noise and spikes, are implicated in muscle function and dysfunction.
Purpose of the Study:
- To investigate the prevalence of endplate potentials in active MTrPs compared to endplate zones and taut bands.
- To determine the specificity of endplate potentials to MTrPs.
Main Methods:
- Needle examination of 11 muscles in 10 subjects.
- Comparison of endplate potential prevalence at trigger points, endplate zones, and taut bands.
- Electrical identification of endplate zones and MTrPs.
Main Results:
- Endplate noise without spikes occurred in all trigger-point sites.
- Endplate noise was found in 4 muscles at endplate zones outside MTrPs (P=0.024).
- Endplate noise did not occur in taut bands outside endplate zones (P=0.000034).
Conclusions:
- Endplate noise is significantly more prevalent in MTrPs than in adjacent endplate zones.
- Endplate noise appears characteristic of, but not exclusive to, MTrP regions.
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