Appendix (appendix)
Last reviewed: 23.04.2024
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The appendix is anatomically and topographically connected with the cecum, which is an important organ of the immune system.
Appendix (appendix vermiformis) departs from the posterior medial surface of the caecum, its length varies widely - from 2 to 24 cm (average 9 cm); its diameter is 0.5-1.0 cm. The appendix can have a diverse direction. Usually the appendix is in the right ileal fossa, but can fall into the cavity of the small pelvis. The direction of the appendix can be downward (40-45%), lateral (17-20%) or ascending (13%). In the ascending direction, the appendix is often located behind the cecum (retro-intestinal position) or is located even aboriginally. Usually the appendix has a mesentery connecting it with the wall of the cecum and the terminal part of the ileum.
From a practical point of view, it is very important to know the projection of the base (beginning) of the appendix to the anterior wall of the abdominal cavity. The base of the appendix is projected onto the anterior abdominal wall at the boundary between the outer and middle third of the line connecting the right upper anterior iliac spine and the navel (McBurney point).
However, this position of the appendix is rare. Most often, the base of the appendix is projected on the border between the outer and middle third of the line connecting the right and left upper anterior iliac spines (Lantz point).
