Healing after surgery for an anal fistula requires some time, and the longer healing duration is mainly related to two factors:

The first reason is that anal fistula is a localized infectious disease of the anus with the presence of a fistula. The principle of surgery is primarily to remove the fistula. Therefore, after the surgery, the wound surface from the removed fistula wall is relatively large and requires time to heal.

The second reason is that the local area around the anus is a contaminated wound, with feces passing through daily. Feces are a significant source of contamination, so the wound healing is influenced by the irritation from feces, resulting in a non-sterile wound environment. Consequently, the wound healing rate after the surgery is slower compared to the healing rate of sterile wounds in other body tissues. Therefore, the recovery time after anal fistula surgery is approximately 3 to 4 weeks.