The rubber band is usually used in the surgery of high complex anal fistula, generally in the surgery to make an incision in the external ulcer, and then cut it all the way down to the anal sphincter, and then use the probe or curved forceps to continue to probe along the fistula, see the inner mouth, and then put the rubber band from the anus, pulled out by the curved forceps through the inner mouth, and then the curved forceps tighten the two ends of the forceps under the 10-gauge wire knot, the rubber band Tighten. Generally in about 7 days will check the elasticity of the rubber band, if the rubber band is loose, will be reapplied to the local anesthetic, and then tighten it again, so that it again play the role of cutting, generally in about 10 days the rubber band will fall off on its own, this is safer, will not suddenly cut the sphincter and lead to anal incontinence.