The infantile viscera are delicate, and the meridians are not fully developed. Improper nursing, exogenous pathogenic wind and cold or excessive ingestion of raw and cold food impair the middle energizer yang. Cold causes contraction which leads to qi stagnation, giving rise to pain；the infantile ingestion of proper diet, and crapulence or excessive ingestion of heavy food cause food retention in the middle energizer, resulting in qi stagnation and further developing into abdominal pain; yang deficiency of the body, or yang deficiency of the middle energizer due to weakness after illness leads to the splenic dysfunction in transportation and transformation, resulting in internal accumulation of cold and dampness.

In this case, unsmooth qi circulation makes qi and blood deficient, which deprives the body of warmth and nourishment, bringing about abdominal pain; besides, trauma, or postoperative injury of the internal abdominal collaterals causes the internal blood stasis, or chronic disease invades collaterals and results in blood stasis of meridians due to obstructed qi flow, all giving rise to abdominal pain.