What is a trigger point?

What is a trigger point?

The most accepted theory for a trigger point mechanism is that an event of muscular overload causes a prolonged release of calcium from the storage unit for the muscle cell, resulting in a “sticky” area of the muscle. This leads to an area of shortening, or contracture, with compression of capillaries and results in an increased local energy demand and local ischemia (loss of blood circulation) to the area. As a result, you experience pain due to the subsequent release of chemicals.

Myofacial trigger points are an extremely common cause of complaints. Latent trigger points cause a decrease in range of motion (ROM) and stiffness, whereas an active trigger point does all this as well as cause you pain. The severity of the pain caused by trigger points can range from incapacitation pain to a simple decrease range and impaired function. Although some patients describe the pain caused by an active trigger point as excruciating, trigger points in themselves are not life-threatening. They can, however, limit the limit the quality of life.

An active trigger point, when digitally compressed, will reproduce the pain felt in the muscle. When compressed, a latent trigger point will reproduce the same muscle weakness and restricted ROM. Clinically defined as a localized spot of tenderness in a nodule in a taut band of muscle tissue, a patient can identify the trigger point when palpation can reproduce “their” pain. In addition to the reproduced pain, a palpated trigger point will produce a twitch response; a muscle with a trigger point will twitch when the point is compressed.

Carpal tunnel syndrome, bursitis, tendinitis, angina pectoris, and sciatic symptoms, along with many other pain problems, are often misdiagnosed and are, in fact, trigger point referral pain.

Your body’s instinctive reaction to a harmful “event” is to protect itself. It does that by altering the way you move, sit, or stand, which puts abnormal stress on your muscles, tendons, ligaments, and joints. This produces strength and flexibility imbalances in your muscles, as well as postural dysfunctions throughout your body. If that were not bad enough, your blood flow can become restricted to the area and nervous system will start to send out those “referred” pain signals, making assessment and treatment even trickier.

The length of time it takes to release a trigger point depends on several factors, one of which is how long you have had your trigger point. Other factors include the number of trigger points you have, how effective your current treatment is, and how consistently you can administer or receive treatment.

Adapted from Travell & Simons’ Myofascial Pain and Dysfunction: Upper half of body By Lois S. Simons, Janet G. Travell