History of upper respiratory tract infection, tracheitis, constipation patients, especially for elderly constipation with little drinking, due to the weakening of intestinal peristalsis, strenuous defecation can cause a significant increase in intra-abdominal pressure and trigger the disease. It often occurs suddenly, with severe lower abdominal pain, restlessness, and gradually spreading to the midline of the abdomen, but without radiation pain. Sometimes accompanied by nausea, occasionally vomiting, normal urine and feces. Physical examination shows muscle tension in the lower abdomen, and an unclear, fixed mass can be felt in the area of the rectus abdominis.