Trigger point injections are used to treat excruciating painful areas of a muscle, which are categorized by the presence of trigger points. A trigger point is a disturbed area in the muscle that feels either very tight or like there is a knot in the muscle. These can also be categorized by a taut band of muscle, and are tender when deep pressure is applied or there is a palpation.
Trigger points can occur on any part of the body, but the most common areas they develop are neck, back, and shoulders. Trigger pointing can trap and irritate the surrounding nerves and cause referred pain. Referred pain can be felt in another part of the body but in close proximity to the original site. The presence of trigger points can be a muscle problem or secondary to trauma, scar tissue formation, fibromyalgia, surgery and many other conditions.