Patient, female, 37 years old. She was admitted to the hospital with “difficulty in passing stool for three months”. At the time of admission, the patient had difficulty in passing stool, and each bowel movement lasted for more than 20 minutes, accompanied by obstruction and a feeling of incompleteness after passing stool. Finger palpation: There was a narrow ring at the lower end of the rectum, which could not be passed by the index finger. CT: thickening of the mucosa of the lower rectum and several small metals were visible. He was admitted to the hospital and diagnosed with rectal stenosis. He underwent an incision under sacral anesthesia and had a normal bowel movement after the operation. Discussion: 1. The anastomotic nail used in PPH asks for titanium nail, which can generally be removed by itself or after surgery, and will not cause inflammation if it is not dislodged. In this case, the patient did not fall off the titanium nail and inflammatory hyperplasia, may be related to the quality of the titanium nail (the anastomosis of this case is domestic). In addition, postoperative diagnosis in January is conducive to the detection of residual titanium nail. 2. Why did the inflammatory hyperplasia appear after two years? This is a confusing question. During this period, the patient had no other medical or surgical history.