Vermiform Appendix
Arteries of cecum and vermiform appendix. (Appendix visible at lower right, labeled as "vermiform process").
Normal location of the appendix relative to other organs of the digestive system (frontal view).
Latin	dixermiformis
Gray's	subject #942 8711
System	Digestive
Precursor	Midgut
MeSH	Appendix
Dorlands/Elsevier	a_54/12147735

In human anatomy, the vermiform appendix (or appendix, pl. appendices) is a blind ended tube connected to the cecum, from which it develops embryologically. The term "vermiform" comes from Latin and means "wormlike in appearance". The cecum is the first pouch-like structure of the colon. The appendix is near the junction of the small intestines and large intestines. Image File history File links Gray536. ... Image File history File links Stomach_colon_rectum_diagram. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... In biology, an organ is a group of tissues which perform some function. ... Upper and Lower gastrointestinal tract The gastrointestinal tract (GI tract), also called the digestive tract, or the alimentary canal, is the system of organs within multicellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. ... This article or section is in need of attention from an expert on the subject. ... The midgut is the portion of the embryo from which most of the intestines are derived. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo. ... List of bones of the human skeleton Human anatomy is primarily the scientific study of the morphology of the adult human body. ... The cecum or caecum (from the Latin caecus meaning blind) is a pouch connected to the ascending colon of the large intestine and the ileum. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ...

Size and location

The appendix averages 100 mm in length, but can range from 20 to 200 mm. The diameter of the appendix is usually less than 7 to 8 mm. The longest appendix ever removed was that of a Pakistani man on June 11, 2003, at Pakistan Institute of Medical Sciences, Islamabad, measuring 235 mm (9.2 in) in length. ^[1] June 11 is the 162nd day of the year (163rd in leap years) in the Gregorian calendar. ... 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... Pakistan Institute of Medical Sciences is located in Islamabad, Pakistan. ... Islamabad (Urdu: اسلام آباد (Meaning Abode of Islam)), is the capital city of Pakistan, and is located in the Potohar Plateau in the northwest of the country. ...

While the base of the appendix is at a fairly constant location, the location of the tip of the appendix can vary from being retrocaecal to being in the pelvis to being extraperitoneal. In most people, the appendix is located at the lower right quadrant of the abdomen. In people with situs inversus, the appendix may be located in the lower left side. The pelvis (pl. ... In higher vertebrates, the peritoneum is the serous membrane that forms the lining of the abdominal cavity - it covers most of the intra-abdominal organs. ... Situs inversus (also called situs transversus) is a rare congenital condition in which the major visceral organs are reversed or mirrored from their normal positions. ...

Function

Medical literature shows that the appendix is not generally credited with significant function. The appendix is rich in infection-fighting lymphoid cells, suggesting that it might play a role in the immune system.^[2] Whether the appendix has a function, it is routinely removed without any ill effects or side effects. This article does not cite its references or sources. ...

There have been cases of people who have been found, usually on laparoscopy or laparotomy, to have a congenital absence of their appendix. There have been no reports of impaired immune or gastrointestinal function in these people. Laparoscopic surgery, also called keyhole surgery (when natural body openings are not used), bandaid surgery, or minimally invasive surgery (MIS), is a surgical technique. ... A laparotomy is a surgical maneuver involving an incision through the abdominal wall to gain access into the abdominal cavity. ... A congenital disorder is a medical condition or defect that is present at or before birth (for example, congenital heart disease). ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and...

Usually the Appendix can be removed with only a tiny scar.

The most common explanation is that the appendix is a vestigial structure with no absolute purpose. In The Story of Evolution, Joseph McCabe argued thus: The human vermiform appendix is a vestigial structure; it no longer retains its original function. ... Joseph Martin McCabe (12 November 1867 - 10 January 1955) was a well-known atheist. ...

The vermiform appendage—in which some recent medical writers have vainly endeavoured to find a utility—is the shrunken remainder of a large and normal intestine of a remote ancestor. This interpretation of it would stand even if it were found to have a certain use in the human body. Vestigial organs are sometimes pressed into a secondary use when their original function has been lost.

The appendix is more developed in Old World monkeys.^[3]

The appendix is thought to have descended from an organ in our distant herbivorous ancestors called the cecum (or cæcum). The cecum is maintained in modern herbivores, where it houses the bacteria that digest cellulose, a chemically tough carbohydrate that these animals could not otherwise utilize. The human appendix contains no significant number of these bacteria, and cellulose is indigestible to humans. It seems likely that the appendix lost this function before human ancestors became recognizably human. Image File history File links Primates - Old World monkey: 1. ... Image File history File links Primates - Old World monkey: 1. ... Subfamilies Cercopithecinae - 11 genera Colobinae - 10 genera The Old World monkeys or Cercopithecidae are a group of primates, falling in the superfamily Cercopithecoidea in the clade Catarrhini. ... The cecum or caecum (from the Latin caecus meaning blind) is a pouch connected to the ascending colon of the large intestine and the ileum. ... A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ... Cellulose as polymer of β-D-glucose Cellulose in 3D Cellulose (C6H10O5)n is a polysaccharide of beta-glucose. ... Lactose is a disaccharide found in milk. ...

Loren G. Martin^[4], argues that the appendix has a function in fetuses and adults. Endocrine cells have been found in the appendix of 11 week old fetuses that contribute to "biological control (homeostatic) mechanisms." In adults, Martin argues that the appendix acts as a lymphatic organ. This article or section does not cite any references or sources. ... This article does not cite its references or sources. ...

Diseases

The most common diseases of the appendix (in humans) are appendicitis and carcinoid tumors. Appendix cancer accounts for about 1 in 200 of all gastrointestinal malignancies. Appendicitis (or epityphlitis) is a condition characterized by inflammation of the appendix[1]. While mild cases may resolve without treatment, most require removal of the inflamed appendix, either by laparotomy or laparoscopy. ... Picture of a carcinoid tumour that encroaches into lumen of the small bowel. ... Appendix cancer or appendiceal cancer is a malignancy of the vermiform appendix, accounting for about 1 in 200 of all gastrointestinal malignancies. ...

Appendicitis (or epityphlitis) is a condition characterized by inflammation of the appendix. While mild cases may resolve without treatment, most require removal of the inflamed appendix, either by laparotomy or laparoscopy. Untreated, mortality is high, mainly due to peritonitis and shock. Appendicitis presents as pain in the right lower quadrant with rebound tenderness. In particular, it presents at McBurney's Point, 1/3 of the way along a line drawn from the Anterior Superior Iliac Spine to the Umbilicus. Rebound tenderness is when it does not hurt to press on the point but it hurts greatly when the pressure is released, or when the skin rebounds. Typically, point (skin) pain is not present until the parietal peritoneum is inflamed as well. Fever and immune system response are also characteristic of appendicitis.

The surgical removal of the vermiform appendix is called an appendicectomy (or appendectomy). This procedure is normally performed as an emergency procedure, when the patient is suffering from acute appendicitis. In the absence of surgical facilities, intravenous antibiotics are used to delay or avoid the onset of sepsis; it is now recognized that many cases will resolve when treated non-operatively. In some cases the appendicitis resolves completely; more often, an inflammatory mass forms around the appendix. This is a relative contraindication to surgery. An appendicectomy in progress An appendicectomy (or appendectomy) is the surgical removal of the vermiform appendix. ...

Additional images

Location of McBurney's point (#1) Image File history File linksMetadata McBurney's_point. ...	The superior mesenteric artery and its branches. Image File history File links Download high-resolution version (500x609, 136 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Cecum Vermiform appendix Wikipedia:Grays Anatomy images with missing articles 11 List of images in Grays...	The lymphatics of cecum and vermiform process from behind. Image File history File links Gray616. ...	Lymphatics of colon. Image File history File links Gray617. ...
Superior ileocecal fossa. Image File history File links Gray1043. ...	Inferior ileocecal fossa. Image File history File links Gray1044. ...	Interior of the cecum and lower end of ascending colon, showing colic valve. Image File history File links Gray1075. ...	Mucinous adenocarcinoma of the appendix tip Image File history File links Download high-resolution version (2272x1704, 2977 KB) Personal photo I own from a surgery I performed. ...

See also

• McBurney's point

McBurneys point is the name given to the point over the right side of the human abdomen that is one-third the distance from the ASIS (anterior superior iliac spine) to the umbilicus. ...

References

External links

• "The vestigiality of the human vermiform appendix: A Modern Reappraisal" -- evolutionary biology argument that the appendix is vestigial
• SUNY Labs 37:12-0102 - "Abdominal Cavity: The Cecum and the Vermiform Appendix"