The Meridians and Collaterals
经络
The meridian-collateral theory is concerned with the physiological functions and pathological changes of the meridian-collateral system, and their relationships with zang-fu organs. It is an important component of the theoretical system of TCM. Andit is considered as a theoretical basis of all clinical subjects of TCM, especially that of acupuncture and moxibustion, tuina, and qigong. Be-sides, it guides the clinical practice of other branches of TCM. The meridians and collaterals are pathways along which qi and blood circulate through the whole bodily areas to which the regular meridians cannot get. The collaterals are the branches of the meridians. They are divided into three groups, namely the diver-gent collaterals, superficial collaterals and tertiary collaterals. The divergent collaterals are the larger and main collaterals. The divergent collaterals originate from the twelve regular meridians as well as Du and Ren meridians respectively. Together with a large splenic collateral, they are generally called "the fifteen divergent collaterals".Their chief task is to strengthen the links between every pair of meridians exteriorly-interiorly related on the body surface. The superficial collaterals are ones that run through the surface layer of the human body, and often emerge on the surface. And the tertiary collaterals refer to the smallest and the thinnest ones of the whole body.
经络理论是有关经络系统的生理功能和病理变化以及和脏腑之问关系的理论。它是中医理论系统的重要组成部分，被认为是所有中医临床学科特别是针灸、推拿和气功的理论基础。另外，它还指导其他分支学科的临床实践。经络是气血循行全身的通道。经是经络系统的主干，纵行于人体，而络是经的分支，呈网状分布于全身。因此，经络沟通人体脏腑肢节，上下内外，使人体的脏腑组织成为一个有机整体。经络系统由经和络互补而成。这个系统在内联络脏腑组织，在外沟通筋骨肌肤。经可以分为三类：正经、奇经和经别。有十二正经即手足三阴三阳经。它们被总称为“十二正经”，是气血循行的主要通道，有同定的起止点，按照一定的路径循行并按一定顺序交接。它们与相对应的脏腑直接相连。奇经八脉由督、任、冲、带、阴跻、阳跻、阴维和阳维脉组成。它们与十二正经相互联系，并行使控制、联系和调节十二正经的功能。另外，它们不与脏腑直接相关。十二经别是十二正经的延续。它们起于四肢，深入脏腑，浅出于项部。它们的作用是加强十二正经表里两经的联系，并补充十二正经所不能到达的脏腑和身体区域。络是经的分支，可分为三类：别络、浮络和孙络。起源于十二正经和任督二脉的别络和脾之大络统称为”十五别络”。它们的作用是加强表里两经在体表上的联系。浮络循行于人体的表层并常出于体表。孙络是整个人体中最细小的络脉。