A Myofascial trigger point (TP) is a hyperirritable point within a taut band of skeletal muscle, located in the muscular tissue and/or its associated fascia. The spot is painful on compression and can evoke characteristic referred pain and autonomic phenomena. A Myofascial TP is to be distinguished from a trigger in other tissues, such as skin, ligament, and periosteum.

We classify Myofascial TPs as either active or latent. An active TP causes the patient pain. A latent TP is clinically silent with respect to pain, but may cause restriction of movement or weakness of the affected muscle. A latent TP may persist for years after apparent recovery from injury; it predisposes to acute attacks of pain. Both latent and active TPs cause dysfunction; only active TPs cause pain.

Normal muscles do not contain TPs. Normal muscles have no taut bands of fibers, are not tender to firm palpitation, exhibit no local twitch responses, and do not refer pain in response to applied pressure. There are several techniques to treat TPs. These are massage, acupressure, muscle stretching techniques (Postisometric Relaxation), ultrasounds, electrical muscle stimulation, and ischemic compression.

Ischemia means a lack of blood supply, with associated tissue irritation and congestion. The purpose of ischemic compression is to deliberately increase the blockage of blood to an area so that, upon release, there will be a resurgence of blood. This washes away waste products, supplies necessary oxygen and helps the affected tissue to heal. This increase of blood flow to the area is called a hyperemia. To apply ischemic compression to a trigger point, the relaxed muscle is stretched to the verge of discomfort. Initially, a thumb (or strong finger) is pressed directly on the TP to create tolerably painful (7 to 8 on a client pain scale of 10), sustained pressure. Treatment is useless if the patient tenses the muscles and so protects the TP from pressure. As the discomfort tends to abate, pressure is gradually increased by adding a thumb or finger from the other hand, as necessary, for reinforcement. This process is continued up to 1 min. with as much as 20 or 30m lb. of pressure.