Abdominal pain is a common manifestation of many diseases in the abdominal cavity and is divided into 5 major categories according to the etiology of occurrence: 1, inflammatory diseases: including cholecystitis, cholangitis, liver abscess, gastroenteritis, appendicitis, colitis, pancreatitis and other inflammatory stimuli of various organs can cause abdominal pain, when the inflammation is confined to the dirty peritoneum the pain is more dull and imprecise localization, and it is often difficult for patients to describe it accurately. 2, obstructive diseases: including intestinal obstruction, biliary obstruction, pyloric obstruction and other obstruction of the cavity organs can lead to bile, pancreatic juice, gastrointestinal fluid or food, feces, etc. difficult to pass through the lumen, resulting in accumulation, causing pain. Such pain is often more intense, strangulated, and extremely painful for patients. 3. Perforated diseases: including gastric perforation, intestinal perforation, biliary perforation and other cavity organ rupture, resulting in leakage of digestive fluid, causing chemical irritation and pain. Such perforations are often rapid waves of acute pain throughout the abdominal cavity in a short period of time. 4, embedded necrosis: including intra-abdominal hernia or extra-abdominal hernia causing intestinal, omental, gastric and other organs embedded, ischemic necrosis occurs in severe cases, causing abdominal pain. Such pain often has a gradual aggravation process, local masses can be palpable 5, vascular diseases: including arterial abdominal aortic aneurysm, mesenteric artery embolism and venous portal vein thrombosis, mesenteric vein thrombosis, etc., resulting in blood supply or reflux disorders, causing ischemic necrosis or swelling of the organs, causing abdominal pain. Arterial abdominal pain is more severe, and the subjective description of the patient is extremely serious but the objective examination is sometimes difficult to find abnormalities, which can easily lead to misdiagnosis and delayed diagnosis. Venous disorders are slow in onset and progressive in severity, and are often associated with other diseases, such as tumors and bacterial infections. These five types of causes are the main causes of abdominal pain, and the five causes can intersect and promote each other as the initiating factors. Sometimes a disease can have several factors involved together or at different stages, such as common bile duct stones, which are initially obstructed by the common bile duct and then can be followed by biliary tract infection, and further aggravation can lead to bile duct perforation, etc. Other factors that are not true abdominal pain also need to be identified, such as injury to the abdominal wall, herpes zoster, costochondritis, pleurisy, coronary artery disease, etc.