Appendix

The appendix is an intraperitonal, narrow, muscular tube attached to the posteriomedial surface of the cecum. It is located about 2.5 cm below the ileocecal valve.

Its surface marking can be described as being located at McBurney’s point. This is the junction of the lateral third and medial two thirds of an imaginary line draw from the right anterior superior iliac spine to the umbilicus.

Blood Supply

The appendicular artery supplies the appendix.

Venous Drainage:

The posterior cecal vein drains the appendix.

Innervation

It receives parasympathetic innervation from the vagus nerve via the superior mesenteric plexus. It receives sympathetic innervation from T10 sympathetic nerves.

Clinical Notes:

The appendix is predisposed to infections because it is a narrow and blind-ended tube, it’s lumen can be obstructed, and it’s walls contain large amounts of lymphoid tissue.

Pain from the appendix is referred to the T10 dermatome over the region of the umbilicus. Localized pain is concentrated over the region where an inflamed appendix has infected the peritoneum of the greater sac.