J Rehabil Med Suppl 41, 2003 DOI 10.1080/16501960310010205 Referred muscle pain, resulting from algogenic conditions in viscera or other deep somatic structures (another muscle, a joint), is most often accompanied by secondary hyperalgesia and trophic changes (hypotrophy). Referred pain/ hyperalgesia from viscera is partly due to central sensitisation of viscero-somatic convergent neurons (trig...