Pressure threshold is the minimum pressure inducing pain or discomfort. A force gauge (11-kg gauge), to which a rubber disc with an exactly 1-cm2 surface is attached, has been proven to be adequate for quantification of tenderness in soft tissues. The pressure threshold measurement (PTM) is useful for documentation and identification of tender spots, as well as quantification of the degree of tenderness (pain). Normal values were established in 24 male and 26 female volunteers at nine different sites, frequently affected by trigger points, including trapezius, supraspinatus, infraspinatus, teres major, lumbar paraspinals, (two sites), and gluteus and pectoralis muscles. The deltoid was used as reference for usually normal muscle sensitivity. The clinical use of PTM is discussed, and includes quantification of tenderness for medicolegal purposes, but primarily to prove to patients and other health professionals the presence of trigger points or tender spots. The reaction to different treatment modalities, such as physiotherapy and drugs, can be assessed quantitatively. After properly administered trigger point injections, consisting of needling of entire abnormal area, PTM increases, usually by 4 kg/cm2. Failure to raise PTM indicates that the injection was incomplete, and the procedure should be repeated. PTM correlates well with changes of clinical status and can be used for monitoring tenderness, inflammation, and the activity of arthritis.