Generally, when patients complain of burning or severe pain in the anus after relieving dry stools, it is generally estimated that they have anal fissures. Physiological state, when the feces into the rectum and produce stool, anal sphincter began to diastole and contraction, ready for defecation. If you encounter coarse and hard feces through the anal canal, impact and tear the anal canal and cause anal fissure, it will cause severe pain. Due to the spinal nerves in the anal canal, the pain is very obvious and lasts for about 30 minutes. When the sphincter muscle spasms and contracts to the point of fatigue and weakness, the pain will be gradually reduced, and then the anal sphincter muscle will start to spasm, and the pain will be aggravated, and the pain will last for several hours, making the patient in great pain. Thus, the fear of defecation, will not be able to hold back the stool, and this will be the stool is more coarse and dry, the street further aggravate the degree of anal fissure, the formation of a vicious circle. Anal fissure is generally a longitudinal fissure of the skin of the anal canal, located between the anal verge and the toothed line. Generally external forces to anal fissure as the main factor, other such as local injury, chronic inflammation of the anal canal, congenital anal canal stenosis and other reasons. The main symptom is painful defecation with a small amount of blood in the stool. Early anal fissure (a), that is, fresh fissure only need to soften the stool, local anti-inflammatory cream, generally can be self-healing. Second and third stage anal fissure, or old anal fissure, need surgery. Patients generally have the above symptoms, should seek timely medical treatment to avoid anal fissure infection.