On the segmental and tagmatic phenomena inferred from referred pain and autonomic concomitants.

Visceral injury induces referred pain, autonomic concomitants, skeletal muscle spasm, and hyperalgesia of segmental pattern on the specific area of somatic tissue. Therefore, since visceral referred pain does not mean only a feeling which is considered as misperception of brain but accompanies accessory phenomena, referred phenomenon can be more reasonable expression. Visceral referred phenomenon has segmental pattern and is shown on the segmental constituents related to viscus and further spreads to multi-segments through central sensitization if visceral injury become severe and chronic. Segmental pattern observed in our body is not a feature developing only in human. Segmentation of animals is a general concept in body organization from Annelida to Vertebrata. The evolutionary advent of segmentation made possible development of much greater complexity in structure and function. Segmentation increased efficiency of movements, and further made fine neural control of movements possible. It is definite that segmentation of body bestows obvious advantages to an animal. If abnormality in a segment develops, to lessen energy expenditure of an organism consisting of multi-segments, the organism sacrifices the abnormal segment for the whole segments via defunctionalization. Defunctionalization of abnormal segment is just segmental phenomenon. Functional unit of grouped segments called as tagma in Arthropoda or its equivalent in Vertebrata could also show this phenomenon if abnormality develops in tagma or its equivalent. Visceral referred pain, referred pain originating from musculoskeletal structure, complex regional pain syndrome I and II are representatives of segmental or tagmatic phenomena.