Myofascial pain syndrome (MPS) is defined as a chronic, regional pain The hallmark classification…

Myofascial pain syndrome (MPS) is defined as a chronic, regional pain The hallmark classification of MPS comprises the myofascial trigger points (MTrPs) in a muscle that have a specific referred pattern of pain along with sensory, motor, symptoms. The trigger point is defined as a hyperirritable area in a tight band of muscle. The pain from these points is described as dull, aching, and deep. Possible Causes of Trigger Points Although the etiology of trigger points is not completely understood, some potential causes are ■ Chronic overload of the muscle that occurs with repetitive activities or that maintain the muscle in a shortened position. ■ Acute overload of muscle, such as slipping and catching oneself, picking up an object that has an unexpected weight, or following trauma such as in a motor vehicle accident. ■ Poorly conditioned muscles compared to muscles that are exercised on a regular basis. ■ Postural stresses such as sitting for prolonged periods of time, especially if the workstation is not ergonomically correct, and leg length differences. ■ Poor body mechanics with lifting and other activities.