The duodenum is a mostly retroperitoneal organ, part of the digestive tract, and the most proximal portion of the small intestine. This organ is approximately 10 inches in length (24.5 cm). It starts at the pylorus of the stomach, has a "C" shape, curving around the head and the neck of the pancreas, to end at the duodenojejunal junction.
The duodenum is described as having four segments of differing length, usually named numerically:
- First segment: about two inches in length, it is dilated and called the "duodenal ampulla", or "superior duodenum"
|Image property of:CAA.Inc.Artist:Dr. E. Miranda|
|The name of the organ is interesting. Most textbooks claim that is originates from the Latin [duodeni], meaning "twelve". The fact is that the duodenum was originally named in Greek [δώδεκα δάχτυλαν] meaning "twelve fingers". If you place both your hands together and add 1/4 of an inch to each side (as if you had an extra finger on each hand) that measures approximately 10 inches. The term was shortened by an incorrect translation to "twelve" by Gerard of Cremona (1114 - 1187) who called it "duodenum", a bad translation, as twelve fingers in Latin is [duodecim digitorum].