The risk of sacral canal cyst surgery is about 5%-10%, because sacral canal cyst surgery is relatively traumatic, although bleeding can be avoided by a series of microscopic operations and meticulous operations, but after all, it involves neurovascular and also bony problems. The first point, the bleeding problem after sacral canal cyst surgery, because after all, this place still has a relatively rich blood supply, once the hemostasis is poor, the probability of bleeding will be formed. The second point, the situation of intracranial infection, because the cerebrospinal fluid is all connected, at this time, if there is an infection, it may develop directly from the sacral canal to intracranial infection, and sometimes the result is irreversible and very serious. The third point is that the nerve is damaged, because the sacral canal cyst is mainly compression symptoms, compression of the nerve, the surgery to be done is to separate the nerve, in the process of separation may damage the nerve, resulting in more serious symptoms. Therefore, sacral cysts must be taken seriously.