Qi stagnation syndrome refers to symptoms caused by qi stagnation in a certain region or a certain viscera in the human body. The causes of qi stagnation syndrome are various, such as emotional upsets, improper diet, attack by exogenous pathogenic factors, asthenia of yangqi, or trauma, falling, contusion and sprain which all may lead to dysfunction and disturbance of qi and bring about qi stagnation.

Clinical manifestations:
Distending oppression, pain (distension is more serious than pain) or migratory pain and attacking pain are felt over the chest, hypochondriurn, epigastrium and abdomen. The location of pain and distension is usually unfixed. The distension cannot be felt by palpation but is alleviated after sighing, borborygmus and breaking wind. It may be attenuated or worsened with the changes of emotions.

Analysis of symptoms:
Normally qi should be free and smooth in flowing, stagnation will lead to distending oppression in mild case and pain in severe case; qi sometimes gathers up and sometimes disperses, so the location of pain is not fixed, pain is now serious and then light and it cannot be felt by palpation; sighing, borborygmus and breaking wind smooth the flow of qi, that is why distension and pain are alleviated; hyponchondriac distension and pain are due to emotional upsets and stagnation of liver qi which prevent free dispersion and inhibit flow of meridian qi；distending oppression of chest is due to stagnation of pulmonary qi; epigastric and abdominal distending pain is due to stagnation of gastric and intestinal qi; oppression and pain over the chest is due to obstruction of heart qi and inhibited flow of blood in vessels.

Key points for syndrome differentiation:
Local distending oppression and pain. The symptoms are usually various due to different causes of qi stagnation and pathological changes of different viscera. So cares should be taken to differentiate the location of distending oppression and pain as well as the accompanied symptoms.