The meridian begins at the inner nail corner of the big toe, follows the border between the pale and darker skin of the inner foot, passes in front of the medial malleolus and rises up the inner aspect of the leg. It crosses the Liver meridian four finger-widths above the malleolus, continues along the inner thigh, enters the abdomen, reaches the spleen and stomach, crosses the diaphragm and travels up the throat to the root of the tongue. An external branch rises up the chest and ends on its lateral aspect.
The Spleen governs transformation and transport: it extracts from food the essence that will become Qi and Blood. It raises the clear towards the Lung and Heart, and holds the organs in place. It keeps Blood within the vessels, hence its role in bleeding, heavy periods and spontaneous bruising. It commands the muscles and the four limbs, opens into the mouth and manifests in the lips. Excessive thinking and rumination exhaust it.