Updated: May 1, 2020
What is it?
A trigger point or knot is a localized tender hardening that lie in a palpable taut band within a muscle. Trigger points may also reside in other soft tissues such as ligaments and tendons. They can refer pain, cause discomfort, stiffness, limited motions, and muscle weakness. Local twitch response creates a visible contraction.
There are two types of trigger points, active and latent. Active trigger points cause pain when compressed; the person recognizes it as familiar. Latent trigger points have the same characteristics as active but cause no pain until compressed and the person does not recognized the pain as familiar. When latent trigger points are found during palpation, the client may comment, "I didn't even realize it hurt there."
Why does it happen?
There are several hypothesis explaining how a knot or trigger point develops. The most widely accepted one is the integrated hypothesis, in which it states that the development begins when precipitating events (muscle strain, overuse, or direct trauma) cause an excessive release of acetycholine- a neurotransmitter- by presynaptic neurouns. This "triggers" an increase in muscle tension, shortened muscle fibers, and taut bands. Taut bands cause localized ischemia, which creates local oxygen and nutrient deficiencies and reduce energy production in muscle fibers.
Other factors contributing to trigger point developments are diseases and disorders such as myofascial dysfunctions, arthritis, temporomandibular joint dysfunction, structural asymmetry, among others.
How can I relive it?
Trigger Point Therapy seems to help as the compression, transverse friction, and other techniques seem to deactivate trigger points.
Other methods are local injections of anesthetics, dry needling, and acupuncture.