Trigger points are the clinical name for contracted muscle knots. These knots are the result of an overload stress placed on the muscle tissue. This overload can be from both acute or chronic stresses. When this happens some of the muscle fibers get locked together in a maximally contracted spasm that self perpetuates. These trigger points then cause symptoms such as pain, referred pain, stiffness, and weakness. They are one of the most common source of pain in the human body, and can even mimick symptoms of other conditions. Trigger points don’t go away on their own, they also can’t be treated with stretching, rest or rehabilitation exercises. A direct intervention targeted directly at the point itself such as trigger point massage therapy is the only way to release a trigger point.
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The supraspinatus muscle makes up part of the rotator cuff. It is responsible for assisting in shoulder abduction as well lateral rotation and stabilizing the shoulder joint. This muscle is often overloaded in labourers and tradesman who have to do a lot of overhead work. Athletes who do a lot of throwing movements will also frequently have Tigger point in this muscle. These trigger points will cause pain to be felt into the shoulder and down the arm, as well as stiffness and weakness.