Acute appendicitis presents with the classic clinical symptom of metastatic right lower abdominal pain, mainly because the anatomical location of the appendix is in the right lower abdomen, and the afferent nerves that feel pain when there is appendicitis inflammation are mainly the sympathetic nerves and the small visceral nerves. When acute appendicitis first develops, it usually manifests as pain in the umbilicus, left side or upper abdomen, and as the inflammation gradually strengthens and the irritation becomes clearer, it is concentrated in the right lower abdomen. Of course, not all appendicitis presents with the typical metastatic right lower abdominal pain, some start with right lower abdominal pain, and the pain of a specifically located appendix may be in the right upper abdomen, pelvis or in the left lower abdomen.