Cecum, lat: caecum


The appendix is ​​a part of the human digestive system.
In the strict sense of the word as appendix (Cecum) is called the first section of the colon. It joins the small intestine and lies in front of the colon (colon). Incorrectly referred to as the appendix in the vernacular, the worm foret (Appendix vermiformis), which is only an appendage of the actual appendix (Cecum) is.

Further information on the anatomy of the abdominal cavity can be found here: Abdominal cavity

Structure of the appendix

The cecum lies in the right central abdomen and is only a few centimeters long. It forms the initial part of the large intestine and is therefore actually a sack-shaped protuberance of the ascending colon (Ascending colon), which ends blindly, which explains the naming.
Directly in front of the appendix lies the last part of the small intestine, the ileum (Ileum). The transition from the ileum to the cecum is formed by a valve, the so-called ileocecal valve or Bauhin valve. Due to the special folding of the mucous membrane, it normally only opens in the direction of the large intestine, thus preventing the bacteria, which colonize the large intestine in large numbers, from entering the small intestine, which is much less germinated.

The appendix is ​​richly populated with immune defense cells, which in their entirety are GALT (well-associated lymphatic tissue, in English roughly: intestinal-associated immune system). Especially in the appendix there are accumulations of lymphatic cells, these accumulations are called Peyer's plaques.

The appendix (also the "appendix" of the vernacular, lat .: Appendix vermiformis) is an appendage of the caecum and usually measures 5-10 centimeters. The position of the appendix is ​​quite variable, but the most common position is behind the cecum (retrocaecal). It can be projected onto the so-called McBurney point from the outside. If you draw an imaginary line between your navel and your right Anterior superior iliac spine (upper iliac spine, palpable as the "hip bone") this point is on the first third of the iliac spine. Often there is pain on pressure or pain in letting go in this area (as well as at the Lanz point) with inflammation of the appendix, but it can only be used as an indication, not as reliable evidence.

The layering of the inner lining of the caecum corresponds to that of the rest of the digestive tract. The innermost layer is the mucosa (mucous membrane), which borders on a thin layer of connective tissue, the submucosa. This is followed by a layer of smooth muscle (Tunica muscularis), which is controlled in its activity by the vegetative (autonomous) nervous system.

You may also be interested in this topic: Digestive tract

Size of the appendix

The real appendix as part of the large intestine has a length of about 6 to 8 cm in humans. The appendix, which is colloquially very often referred to as the appendix, which extends from the actual appendix, can vary much more in length and size.
In most people, the appendix is ​​5 to 10 cm in length. In some cases it can nonetheless be up to 20cm or even 2cm long. The appendix is ​​a very slender organ and has a diameter of about 6 to 7 mm.

Similar topics you might be interested in:

  • Intestinal flora
  • Rectum

Illustration of the appendix

Figure appendix with appendix
  1. Appendix - Caecum
    (Light blue border)
  2. Opening the Bauhin flap -
    Ostium ileal
  3. Mouth of the appendix -
    Ostium appendicis vermiformis
  4. Free tape strip -
    Taenia libera
  5. Appendix -
    (Light green border)
    Appendix vermiformis
  6. End part of the ileum -
    Ileum, pars terminalis
  7. Ileum-appendix valve
    (Bauhin flap) -
    Ileal papilla
  8. Transverse folds of the colon -
    Plicae semilunares coli
  9. Colon, ascending part -
    Ascending colon

You can find an overview of all Dr-Gumpert images at: medical illustrations

Which side is the appendix on?

The real appendix lies on the right side of the lower abdomen in almost everyone. In some cases, however, the appendix can be significantly longer (up to 20cm!), Which means that in some people it can even reach into the left lower abdomen.

Also read: Vascular supply of the intestine

Function of the appendix

The cecum does not have a prominent function, it is used for the passage of food. The function of the appendix is ​​the subject of many considerations, meanwhile it is no longer regarded as a completely functionless remnant of evolution, but rather as a part of the body's immune system and the lymphatic system.

Recent research has raised the suspicion that bacteria are located here that are said to have a positive effect on the human organism. However, especially in the highly developed countries with high hygiene standards, this function of the appendix has hardly any significance. This can also be seen from the fact that removal - as is the case with appendicitis (Appendicitis) is often necessary and practiced - brings no disadvantages in the industrialized nations.

Read more on this topic:

  • Task of the appendix
  • Functions of the Colon
  • Task of the small intestine

Diseases of the appendix

By far the most common disease in the area of ​​the appendix is ​​appendicitis, an inflammation of the appendix, popularly called appendicitis.
With around 100 cases per 100,000 inhabitants per year, it occurs very frequently in western Germany, with the incidence peak between the 10th and 20th Year of life.

Appendix irritation

Appendicitis irritation can be thought of as a mild form of appendicitis.
Here, too, a bacterial infection or an occlusion of the entrance to the appendix (appendix) lead to inflammation. The consequences are pain, which initially appears dull and difficult to localize in the upper abdomen or around the navel. They can later migrate to the right lower abdomen. The pain is typically accompanied by nausea, vomiting, fever and diarrhea. In contrast to fully developed appendicitis, the symptoms here are usually rather mild.
Treatment can therefore often be carried out simply by administering antibiotics and bed rest. An operation with removal of the appendix (appendectomy) can usually be dispensed with in the event of appendix irritation. Nonetheless, any irritation of the appendix that has already gone through can favor a recurrence of the symptoms up to appendicitis.


Appendicitis, called appendicitis in technical terms, is a very common clinical picture, especially in children, but also in adults.
The term actually refers to an inflammation of the appendix, the appendix, which comes off the actual appendix, the first part of the large intestine, as a small appendage. Appendicitis is typically caused by obstruction of the entrance with fecal stones or small pits of fruit. Inflammation as part of a bacterial infection of the intestine is also possible less frequently.
The typical symptoms of appendicitis are dull pains that are difficult to localize in the upper abdomen or the navel, which migrate to the right lower abdomen over the course of hours or a few days and become more acute here. In addition, there are often nausea, vomiting, fever and diarrhea, as well as defensive tension in the abdominal muscles. These complaints in combination with a specific physical examination are often enough for the treating doctor to diagnose appendicitis. In addition, however, the diagnosis can be confirmed by ultrasound and blood sampling.

Even if this is a very common clinical picture, appendicitis can be a dangerous exception. As a result, surgical removal of the appendage (appendectomy) usually has to be performed. In some cases, antibiotics and bed rest for a few days can be used.

Further information on this topic can be found at:

  • These are the symptoms you can tell if you have appendicitis
  • Surgery for appendicitis

Appendicitis as a complication of appendicitis

The treatment of appendicitis is often uncomplicated. A large number of patients will be symptom-free within a few days after the operation or even only through targeted antibiotic therapy and will be able to go back to their everyday lives.
Nonetheless, appendicitis is always a potentially life-threatening clinical picture. The cause for this lies in the rupture of the appendix, the appendix perforation, as the maximum form of inflammation. The attacked and weakened intestinal wall tears, so that the bacteria in the appendix spread into the actually sterile abdominal cavity and lead to extensive inflammation of this. A typical sign of a ruptured appendix is ​​a decrease in pain due to the decrease in pressure within the appendix, which had previously led to the painful tension in the wall of the appendix. This is known as what is known as a "lazy peace". If left untreated, it inevitably leads to sepsis and ultimately death.

For this reason, if perforated appendicitis is suspected, treatment must be given immediately. In advance, an X-ray image of the abdomen can be made, in which free air can be seen in the normally air-free abdominal cavity. In most cases, however, this is not done and an open surgical removal of the appendix is ​​carried out and, as part of this, the abdominal cavity is rinsed to remove intestinal contents and pathogens. Antibiotics will then be used over the next few days to reduce the infection.

Read more on this topic at: Ruptured appendix

What does the appendix scar look like?

For the surgical removal of an inflamed appendix, the surgeon basically has two options to choose from. '
The more traditional variant is the open surgical procedure. For this, a 3 to 4 cm long, oblique incision is made in the right lower abdomen, through which the appendix can then be removed. This surgical method is called an alternating incision and leaves a typical, correspondingly short scar. It is mainly used for emergency appendectomy or if the patient has already been operated on.

The surgical method that has become much more popular is the so-called laparoscopic removal of the appendix. For this purpose, only three small access routes are created in the abdominal cavity, via which a camera and the necessary instruments are then introduced into the abdominal cavity. Access is via the navel and one each in the area of ​​the right and left lower abdomen. The resulting scars will be about half a centimeter to one centimeter long and therefore hardly visible, for which reason this variant is mostly preferred today.

More on this: Appendectomy

Where exactly is pain localized?

Appendicitis is the most common cause of appendicitis pain.
Initially, there is dull, imprecisely localizable bowel pain (visceral pain) in the middle or upper abdomen. After the bacteria have migrated through the intestinal wall to the outside, after 8-12 hours a permanent, precisely localizable "Point pain" on. Its location depends on the location of the appendix and it is aggravated by walking or coughing.

If the appendix lies normally (it hangs down), the pain occurs at the right third point of the line between the two hip bones (Lanz point) or at the right third point of the line between the right hipbone and the navel (McBurney point) on. If it lies in a low position (it hangs in the pelvis), the pain mainly occurs during a rectal or vaginal examination. There is an urge to urinate and defecate due to irritation of the pelvic organs.
If the appendix is ​​located behind the actual appendix, the abdominal pain may be absent and is often replaced by pain in the right flank. In addition, pain occurs when the stretched right leg is lifted, as the appendix comes to rest on the corresponding muscle (M. iliopsoas).
In the elderly and diabetics, the pain is often minimal and difficult to localize. In pregnant women, the appendix is ​​shifted up through the uterus, so that the pain often occurs next to the navel or in the right upper abdomen.

Inflammation in the other sections of the intestine can spread to the appendix and cause pain there. The chronic inflammatory bowel diseases Crohn's disease and ulcerative colitis should be mentioned here in particular.

Another reason for pain in the appendix is ​​twisting (Torsion) the same about its vessel suspensions. Pushing intestinal sections into one another (Intussusception) is possible. These processes usually lead to an intestinal obstruction with the typical cramp-like pain (Colic).

In patients with a suppressed immune system (e.g. after chemotherapy, patients with AIDS or elderly people) it can lead to inflammation of the actual appendix caused by bacteria of the intestinal flora (Typhilitis). This usually results in fever and tenderness in the right lower abdomen.

Read more on the topic: Appendix pain