Trigger points can be found in muscles, connective tissue(tissue that holds us together), and periosteum (the thin sheet-like covering on bones) and manifests as pain. This point of pain is caused because the demand of blood supply is much higher than the actual blood supply to that area.
In 1973, Awad examined biopsy tissues from “muscle trigger points” using an electron microscope and found serotonin and histamine in excess in trigger point areas. This is the result of an increase in platelets and mast cells in the area in response to the body’s demand for increased blood supply. This in turn is a response to increased or heightened activity in a muscle(s) or internal organ(s), i.e. viscera or emotional turmoil that is manifested as:
muscle strain or spasm,
viscerospasm, e.g. spasm of the gall bladder or kidney, or
heightened psychogenic neuromuscular mechanism.
In the first case of muscle strain or spasm, reflex low grade tension in the muscle results. According to histologically conducted studies by Heine, 1997 and Gogoleva, 2001, “low grade tension in the skeletal muscles and fascia are responsible for the low grade inflammation around the terminal parts of the sensory and motor neurons which end in the soft tissues. This inflammation activates the local fibroblasts, which deposit collagen around the nerve endings forming so-called “collagen cuffs”. This additional irritating factor triggers an afferent sensory flow to the central nervous system which is interpreted by the brain as pain. This mechanism partially describes generation of pain in the area of muscle trigger points.”
In the case of trigger points in the skeletal muscles which are developed as a result of chronic visceral disorders. In 1955 Dr. Glezer and Dalicho proposed that “patients with cardiac disorders exhibit active trigger points in the trapezius, levator scapulae, rhomboideus muscles. In such cases the end-plate abnormalities do not have anything to do with formation of trigger points in the skeletal muscles. They are the result of the phenomenon of convergence of pain stimuli within the same segments of the spinal cord which are responsible for the innervation of both the affected inner organ and skeletal muscles.” To that end they have been successful in developing and proposing maps of reflex zone abnormalities in skin, fascia and muscles, including trigger point development.
In the case of psychogenic neuromuscular responses the explanation for their development mimics the cause of trigger points as in muscle strain or spasm.
Muscle trigger points can typically be found easily. The video below describes how this can be done.
Treating muscle trigger points is mandatory because of the vasomotor response. For example, according to Lyn Paul Taylor, A.A., B.A., M.A., R.P. “trigger point formations housed in the upper trapezius and scalenus muscles may, through this developmental process, precipitate a shoulder-hand syndrome (reflex dystrophy) as muscle splinting and vascular changes progressively involve the whole upper extremity.” Very important is also the fact that primary and secondary trigger points exist. Treatment of the primary muscle trigger point is obviously the only successful method.