you completely forgot about squatting. Appendicitis is a disease of westernized countries, virtually unknown in the developing world. The reason is that the cecum was designed to be squeezed empty by the right thigh, in the squatting position. On a sitting toilet, it is physically impossible to compress the cecum. The back-pressure can also overwhelm the ileocecal valve, whose purpose is to protect the small intestine from fecal contamination. Barium enema exams and intestinal surgeries routinely show the leakage of wastes into the small intestine. Crohn's Disease develops in the area soiled by this toxic backwash.
Despite all the straining, the cecum never gets evacuated. Residual wastes adhere to the colon wall, increasing the risk of cancer and inflammation (including appendicitis.)