Vasomotor responses and hyperalgesia observed in the area of TrPs related referred pain can be also attributed to possible sympathetic mechanism. Interestingly, for years MPS has been defined as nociceptive pain, but today the importance of sympathetic nervous system (SNS) activity for MPS pain propagation is indicated more and more frequently. Both are not cheap or easily accessible thus, TrP confirmation is still based on palpatory diagnostic criteria defined by Travell and Simons. Two new methods, sonoelastography and magnetic resonance elastography, have been recently introduced allowing noninvasive imaging of TrPs. Nevertheless, a grown interest in MPS has been lastly observed and the main controversy around pain studies, namely, an objective confirmation of TrPs presence, is again the main research theme. Unfortunately, this MPS is drug-resistant and very often diagnostically overlooked. It has been estimated that in around 30% of patients consulting for pain in primary care the coexistence of myofascial pain syndrome (MPS) caused by trigger points (TrPs) was confirmed. Most authorities agree that a fair amount of pain is left undertreated, especially in the chronic form. The main problem of the pain research filed is the difficulty with an objective quantification of pain. TTDN is a valid and reliable method for and AURP measurement to support TrPs diagnostic criteria for the gluteus minimus muscle when digitally evoked referred pain pattern is present. The sensitivity for, , AURP, and high isothermal-area was 100% for everyone, but specificity of 100% was for and AURP only. Two components of TTDN validity and reliability, and AURP, had almost perfect agreement according to (e.g., thigh: 0.880 and 0.938 calf: 0.902 and 0.956, resp.).
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Validity and test-retest reliability were assessed concurrently.
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TTDN employs average temperature ( ), maximum temperature ( ), low/high isothermal-area, and autonomic referred pain phenomenon (AURP) that reflects vasodilatation/vasoconstriction. Thirty chronic sciatica patients ( TrP-positive and TrPs-negative) and 15 healthy volunteers were evaluated by TTDN three times during two consecutive days based on TrPs of the gluteus minimus muscle confirmed additionally by referred pain presence. TTDN is a new thermography approach used to support trigger points (TrPs) diagnostic criteria by presence of short-term vasomotor reactions occurring in the area where TrPs refer pain. The aim of this study was to assess the validity and test-retest reliability of Thermovision Technique of Dry Needling (TTDN) for the gluteus minimus muscle.