Trigger Points are overly sensitive, irritated points and bands of pain deep in the muscles. They may radiate or refer pain to other areas of the body. They can also cause muscle weakness and restricted range of motion.
Trigger points can result from a number of causes: direct trauma to the body (such as a blow or a car accident); exposure to cold (such as the draft of an air-conditioner or an open window); and overload, caused by overuse of a muscle and/or chronic postural imbalances.
These factors can cause a muscle to contract. As the contraction is held over time, the muscle becomes fixed in an involuntary holding pattern that can become the source of chronic nagging pain.
An active trigger point is one in which an individual can feel the pain; a latent trigger point is an area of heightened sensitivity in which one feels pain only when pressure is applied to it. Both types can cause a referral of pain to other muscles and even to the organs of the body, often remote from the original trigger point, resulting frequently in such complaints as headaches, indigestion, and upset stomachs.
There are certain common areas of the body that are more susceptible to the development of trigger points and pain because they are located at sites of greater biomechanical stress.
One common site for trigger points to develop is in the trapezius muscle of the shoulder blade and the neck. Trigger points in this area are often associated with pain in the back of the neck and around the eyes and ears, which is why you might experience a tension headache when your shoulders feel sore. Interestingly, one can observe that nearly 75 percent of trigger points are identical with the points used in acupuncture and acupressure.