Myofascial Trigger Point

A myofascial trigger point (TrP) is a self-sustaining irritable area in a taut band of muscle fiber that is felt as a nodule or bump. Unlike the restriction of muscle movement from the dysfunctional fascia, found in fibromyalgia (see the fibromyalgia section on this website), this irritated spot causes gradual shortening of the muscle, which interferes with normal muscle function. This restriction of movement and pressure on the surrounding areas causes weakness and pain. Other related symptoms from untreated trigger points can result depending on trigger point location and the trigger point's relationship to lymph vessels, blood vessels, and nerves. The chronic myofascial pain from trigger points is different from the tender points of fibromyalgia in that they refer pain to other parts of the body and can usually be felt with your fingers unless the muscle is too rigid, behind bone, too deep, or behind other muscles. For instance, you can have hand pain that is really activated by a trigger point in the forearm or higher up. Specific trigger points are mapped according to pain and the symptom referral pattern, and have no relevance regarding the size of the muscle. In some cases, small muscles can cause more problems than larger ones, in part because they often are deeper and harder to treat. (See Hide and Seek). Myofascial trigger points are described as active, latent, satellite, or secondary.

Active trigger point

Unlike "tender points," 'TRIGGER POINTS' are felt by you or the examiner, they radiate pain, restrict motion, and can cause other symptoms depending on the surrounding nerves, lymph system, and blood vessels.

An active trigger point is a trigger point that causes pain at rest. It is always tender, causes shortening of the muscle, weakens the muscle, and causes referred pain on direct compression. An active trigger point can elicit a visible local twitch response when adequately stimulated by compression or needle insertion. It can also produce referred motor and autonomic phenomena in the trigger point reference zone, and can cause the reference zone to become tender.

Satellite trigger point

A satellite trigger point is a trigger point located in the referral zone of the primary trigger point (TrP) muscle. The primary trigger point is the one in the muscle of predominate complaints, by you and the muscle. It is the symptomatic area.

Secondary trigger point

A secondary trigger point (TrP) is a trigger point that develops in a second compensating muscle. This second (or third, or fourth…) muscle is attempting to compensate for the malfunction of the muscle affected by the primary trigger point(s). In other words, the primary trigger point can cause such muscle dysfunction in one area of the body that the opposing muscle(s) becomes stressed. In people with chronic myofascial pain, this attempt to carry more than its share of the work causes the second muscle to develop a trigger point(s). Trigger points in this compensatory muscle are called secondary trigger points.

Latent trigger point

A latent trigger point is a trigger point that causes pain only when it is compressed or manipulated. Latent TrPs restrict muscle movement, cause stiffness, and cause weakness that persists for years after apparent recovery. They can go unnoticed only to be reactivated from a seemingly minor overstretching, overuse, or injury. Even chilling can cause transition from a latent trigger point (TrP) to an active trigger point. Latent trigger points (TrPs) are little sneaks, "lying in wait" to ambush you when you least expect it.

Understanding that there are different types of trigger points reinforces the need to be in tune with your body. However, knowing what kind of trigger point it is not as important as knowing what they feel like when you run across them. Some will hurt no matter what, others will hurt only when you press on them. Either way, they need to be treated. Treating all the types is necessary for optimal recovery. Don't be lured into thinking you can only treat active trigger points (the ones screaming out). If you do only this, you will continue to have dysfunction from the untreated trigger points and will think there is no hope for successful treatment. Just because the acute pain of a trigger point is dormant, does not mean it is not wreaking havoc. All trigger points are knots of shortened muscle fiber and cause shortening, pain, and dysfunction of the affected muscle. If you don't treat them all, they will eventually become active and you will develop more secondary, satellite, and latent trigger points. You must treat them all.