Rebound pain in the lower abdomen is most often seen when intra-abdominal organ lesions involve the adjacent peritoneum and also in primary peritonitis. Rebound pain is a sign of inflammatory involvement of the peritoneal wall and is most often seen when intra-abdominal organ lesions involve the adjacent peritoneum and in primary peritonitis. So, what causes can cause patients to have lower abdominal rebound pain? The following is a brief introduction: 1, obstruction appendix is a long and thin tube, only one end and the cecum, once the obstruction can make the lumen secretions accumulate, the internal pressure increases, compression of the appendix wall obstruct the distal blood flow. On this basis, the bacteria in the lumen invade the damaged mucosa and cause infection easily. 2, the main factor of infection is the direct infection caused by bacteria in the appendix lumen. If the appendiceal mucosa is slightly damaged, bacteria invade the canal wall and cause different degrees of infection. 3.Other factors that are considered to be related to the pathogenesis include visceral nerve reflexes caused by diarrhea, constipation and other gastrointestinal tract dysfunction, resulting in spasm of the appendiceal muscles and blood vessels, producing narrowing of the appendiceal lumen, impaired blood supply, damaged mucosa, and acute inflammation due to bacterial invasion.