Although trigger points can often be found in areas such as ligaments, tendons, skin and even scar tissue, trigger points are actually small knots in muscles, also known as contraction knots and can be very tender or tense. These tender knots are often the beginning for certain types of pain and ailments.
Two types of trigger points are classified, they are known as active trigger points and latent trigger points. Both these types of trigger points respond to pressure in particular areas when trigger point therapy is applied to the point.
Active trigger points are the cause of muscle spasms and unexplained pain in muscles. This type of pain occurs even without the need for pressure to be present. Latent trigger points are more commonly responsible for ailments such as stiff joints, and restrictions with joint motion experienced with age.