Send to

Choose Destination
Spine (Phila Pa 1976). 1993 Oct 1;18(13):1803-7.

Myofascial trigger points show spontaneous needle EMG activity.

Author information

Department of Neurosciences, University of California, San Diego.


Monopolar needle electromyogram (EMG) was recorded simultaneously from trapezius myofascial trigger points (TrPs) and adjacent nontender fibers (non-TrPs) of the same muscle in normal subjects and in two patient groups, tension headache and fibromyalgia. Sustained spontaneous EMG activity was found in the 1-2 mm nidus of all TrPs, and was absent in non-TrPs. Mean EMG amplitude in the patient groups was significantly greater than in normals. The authors hypothesize that TrPs are caused by sympathetically activated intrafusal contractions.

[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center