A thorough physical examination and a complete medical history are the two key elements for diagnosis. Physical examination will show the location of trigger points and the local response of the taut muscular band. There are usually no neurological deficits or abnormalities in laboratory tests hematological, biochemical or urinary tract, unless there are concomitant diseases such as nutritional or metabolic disorders. Electromyography will show an increase in spontaneous electrical activity at trigger points. X-rays or MRI reveal no pathological changes in the affected muscle or connective tissue. However, these muscles may show altered patterns of increasing their fatigue, stiffness, subjective weakness, pain on movement and slight decrease in range of motion. Furthermore generate pain when undergoing stretching, forcing the patient to avoid such postures and exercises to maintain muscle contractions greater movement restriction condition. It may be possible to use ultrasound to visualize the spasmodic response by stimulating the trigger point, and thermography, to show areas of increased skin temperature in the region of the trigger points.

The algometers are used to quantify the sensitivity of muscle pressure on one point. Are applied perpendicular to the zone of maximum sensitivity. The pressure threshold is the minimum amount of pressure that induces pain. It is considered abnormal if there is a difference of less than 2 kg cm2-1, involved in a normal control point, usually measured on the opposite side.