Anal fistula is the most variable of the anorectal diseases and the most difficult to treat, surgery is currently the only effective treatment, but many patients relapse after surgery, what is the cause? Recurrence is not only a failure of treatment, but will also have a serious impact on the sphincter function of the anus due to the damage to the integrity of the fistula and the scar left by the surgery, which will make it more difficult to operate again. Therefore, it is extremely important to analyze the causes of failure and try to achieve a successful surgery. The internal port is the source of infection of anal fistula, and it is from the internal port that the pathogenic bacteria of the intestinal cavity enter the perianal area to cause perianal abscess and anal fistula, which is generally located at the junction of the rectum and anal canal 3-4 cm inside the anus. The external orifice is the festering mouth of the infected lesion, mostly outside the anal verge, but also in a few cases inside the anus. The most important factor in the success or failure of anal fistula surgery is the accurate localization of the internal orifice and adequate incision of the internal orifice. The external orifice is mostly dominant, while the internal orifice is more than 90% occult. The most important clinical method to locate the internal orifice is by probing or palpating inside the fistula. Because many fistulas have been prolonged for a long time, the fistula is blocked by repeated infections and adhesions, so it is not possible to find them by probing or imaging. Complex fistulas with curved fistulas and multiple external openings also cannot be explored. If you don’t have some clinical experience, and you don’t know the rules of anal fistula formation, often only part of the fistula is cut open during surgery, and the real inner mouth is still there, leading to postoperative relapse. The actual fact is that the actual fistulas are not only a good idea, but they are also a good idea. However, we have found that the hanging procedure is not only painful, takes a long time to heal, and causes heavy damage to the anal sphincter, but also has a high recurrence rate. In both the early fistula wall hanging and the current cut hanging, the method is to put a glue (silk) thread through the outer opening of the fistula and pull it out through the inner opening, tighten the ends of the thread and tie them together. If the fistula is open, the thread is pulled out accurately from the inner mouth and the fistula wall is opened intact and cured, but if the fistula is adhered in the middle or the inner mouth is closed, it is likely that during the threading process the thread will penetrate out of the wall into the outer tissue of the fistula and then come out of the artificially pierced mouth, so that part of the key fistula and inner mouth is missed and not opened, thus causing the operation to fail and recur after the operation. 3. The main foci are not opened What is the main foci? The main foci, according to the importance of different parts of the fistula for treatment, we divide the fistula into main foci and branched fistulae. The main foci are the fistulae from the internal orifice and the anal canal segment connected to the internal orifice, and also the fistulae accompanying the internal and external anal sphincter. In treatment, the main foci must be incised. The external opening and the external fistula connected to it are called branches, which do not need to be opened as long as they are open to drainage. For many reasons, we failed to fully open the main focal point during surgery, either because we did not find the main focal point or because we were concerned about damaging the sphincter muscle to affect the function of anal closure. The main focal point of anal fistula surgery is important to open, but the branched drainage is equally important, if the branched tube is missed in the operation and not dealt with, it will also cause the operation to fail, this situation occurs in the complex anal fistula and a long course of recurrent anal fistula. The most important thing is that you can find the best way to get the most out of your fistula. The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things. The fistula is too deep, the incision is too small and too short and no drainage is placed, or the bronchus is not properly placed, which can cause poor drainage and non-healing of the wound. The post-operative pseudo-healing Post-operative drug exchange is an important part of the surgical treatment of anal fistula. The two ends of the fistula incision are easily touched together after surgery, and if no measures are taken for a long time, the fistula cavity is not completely filled with flesh and the skin at both ends grows together, so the form of healing is called bridge healing, and because it is not true healing, it can cause recurrence, so it is also called pseudo-healing. This is why it is important to not only fill the fistula cavity with a strip of oil and sand, but also to separate the skin of the anal canal on both sides of the break with oil and sand during the dressing change.