Suspensory muscle of duodenum

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Suspensory muscle of duodenum
Duodenumanatomy.jpg
The duodenum. The suspensory muscle of the duodenum attaches to the duodenojejunal flexure, shown.
Gray1056.png
The duodenum and jejunum depicted in situ . The suspensory muscle of the duodenum connects posteriorly to the duodenojejunal flexure, behind the pancreas, shown.
Details
System Gastrointestinal
Origin Connective tissue surrounding coeliac artery and superior mesenteric artery
Insertion Third and fourth-parts of duodenum, duodenojejunal flexure
Nerve Coeliac plexus, Superior mesenteric plexus
Actions Facilitates movement of food; embryological role in fixating jejunum during gut rotation
Identifiers
Latin musculus suspensorius duodeni, ligamentum suspensorium duodeni
TA98 A05.6.02.011
TA2 3781
FMA 20509
Anatomical terms of muscle

The suspensory muscle of duodenum (also known as suspensory ligament of duodenum, Treitz's muscle or ligament of Treitz [1] ) is a thin muscle connecting the junction between the duodenum and jejunum (the small intestine's first and second parts, respectively), as well as the duodenojejunal flexure to connective tissue surrounding the superior mesenteric and coeliac arteries. The suspensory muscle most often connects to both the third and fourth parts of the duodenum, as well as the duodenojejunal flexure, although the attachment is quite variable.

Contents

The suspensory muscle marks the formal division between the duodenum and the jejunum. This division is used to mark the difference between the upper and lower gastrointestinal tracts, which is relevant in clinical medicine as it may determine the source of gastrointestinal bleeding.

The suspensory muscle is derived from mesoderm and plays a role in the embryological rotation of the gut, by offering a point of fixation for the rotating gut. It is also thought to help digestion by widening the angle of the duodenojejunal flexure. Superior mesenteric artery syndrome is a rare abnormality caused by a congenitally short suspensory muscle.

Structure

The duodenum and the jejunum are the first and second parts of the small intestine, respectively. The suspensory muscle of the duodenum marks their formal division. [2] The suspensory muscle arises from the right crus of the diaphragm as it passes around the esophagus, continues as connective tissue around the stems of the celiac trunk (celiac artery) and superior mesenteric artery, passes behind the pancreas, and enters the upper part of the mesentery, inserting into the junction between the duodenum and jejunum, the duodenojejunal flexure. [3] Here, the muscles are continuous with the muscular layers of the duodenum. [1]

Variation

Considerable anatomic variation exists, in terms of length and point of attachment. [4] Despite the classical description, the muscle only solely attaches to the duodenojejunal flexure in about 8% of people; it is far more common, 40 to 60% of the time to attach additionally to the third and fourth parts of the duodenum; and 20 to 30% of the time it only attaches to the third and fourth parts. Moreover, separate multiple attachments are not that uncommon. [1]

According to some authors, who use the original description by Treitz, the muscle may be divided into two sections: a ligamentous portion attaching the right crus of diaphragm to the connective tissue surrounding the coeliac artery and superior mesenteric artery; and a lower muscular portion from the connective tissue attaching to the duodenum. The superior portion is also described as the Hilfsmuskel. [3] [4] These two parts are now considered anatomically distinct, with the suspensory muscle referring solely to the lower structure attaching at the duodenum. [1] [4]

Function

The ligament contains a slender band of skeletal muscle from the diaphragm and a fibromuscular band of smooth muscle from the horizontal and ascending parts of the duodenum. When it contracts, by virtue of connections to the third and fourth parts of the duodenum, the suspensory muscle of the duodenum widens the angle of the duodenojejunal flexure, allowing movement of the intestinal contents. [1] [5]

Embryology

Embryologically, the suspensory muscle of the duodenum is derived from mesoderm. It plays an important role in the embryological rotation of the small intestine as the superior retention band. [1] [3] : 48 

Clinical significance

This ligament is an important anatomical landmark of the duodenojejunal flexure, separating the upper and lower gastrointestinal tracts. For example, bloody vomit or melena, black tarry stools, usually indicate a gastrointestinal bleed from a location in the upper gastrointestinal tract. In contrast, hematochezia, bright red blood or clots in the stool, usually indicates gastrointestinal bleeding from the lower part of the gastrointestinal tract. [6] It is an especially important landmark to note when looking at the bowel for the presence of malrotation of the gut, a syndrome often suspected in young children when they have episodes of recurrent vomiting. Visualising a normal location of the ligament of Treitz in radiological images is critical in ruling out malrotation of the gut in a child; it is abnormally located when malrotation is present. [4]

During a Whipple's procedure, commonly used to treat pancreatic cancer by removing the pancreas, duodenum, and part of the jejunum, the ligament of Treitz is separated from the duodenum and preserved. When the remaining jejunum is anastamosed with the pylorus of the stomach, it may be passed through the ligament. [7]

Superior mesenteric artery syndrome (SMA) is an extremely rare life-threatening condition that can either be congenital and chronic, or induced and acute. SMA Syndrome is characterised by compression of the duodenum between the abdominal aorta and the superior mesenteric artery, and may—when congenital—result from a short suspensory muscle. One surgical treatment is Strong's operation, which involves cutting the suspensory muscle, though this is not often carried out. [8]

History

The suspensory muscle of the duodenum was first named in 1853 by Václav Treitz, as the musculus suspensorius duodeni (in Latin), and described as consisting of a lower muscular portion with a broad base, and an upper tendinous portion blending with connective tissue around the origins of the superior mesenteric and coeliac arteries. It is commonly termed the ligament of Treitz by clinicians and as the suspensory muscle of the duodenum by anatomists. It has also been likened to "a polar ice cap  ... a structure that many refer to but few have seen." [1]

Additional images

Related Research Articles

<span class="mw-page-title-main">Pancreas</span> Organ of the digestive system and endocrine system of vertebrates

The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine gland, i.e., it has both an endocrine and a digestive exocrine function. 99% of the pancreas is exocrine and 1% is endocrine. As an endocrine gland, it functions mostly to regulate blood sugar levels, secreting the hormones insulin, glucagon, somatostatin and pancreatic polypeptide. As a part of the digestive system, it functions as an exocrine gland secreting pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates, proteins and fats in food entering the duodenum from the stomach.

<span class="mw-page-title-main">Gastrointestinal tract</span> Organ system within humans and other animals

The gastrointestinal tract is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines. Food taken in through the mouth is digested to extract nutrients and absorb energy, and the waste expelled at the anus as faeces. Gastrointestinal is an adjective meaning of or pertaining to the stomach and intestines.

<span class="mw-page-title-main">Duodenum</span> First section of the small intestine

The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In mammals it may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest part of the small intestine.

<span class="mw-page-title-main">Ileum</span> Final section of the small intestine

The ileum is the final section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms posterior intestine or distal intestine may be used instead of ileum. Its main function is to absorb vitamin B12, bile salts, and whatever products of digestion that were not absorbed by the jejunum.

<span class="mw-page-title-main">Jejunum</span> Part of the small intestine

The jejunum is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. Its lining is specialized for the absorption by enterocytes of small nutrient molecules which have been previously digested by enzymes in the duodenum.

<span class="mw-page-title-main">Small intestine</span> Organ in the gastrointestinal tract

The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about 5.5 metres long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter.

Articles related to anatomy include:

<span class="mw-page-title-main">Mesentery</span> Contiguous fold of tissues that supports the intestines

The mesentery is an organ that attaches the intestines to the posterior abdominal wall and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intestines, among other functions.

<span class="mw-page-title-main">Abdominal aorta</span> Largest artery in the abdomen

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<span class="mw-page-title-main">Celiac artery</span> First major branch of the abdominal aorta

The celiacartery, also known as the celiac trunk or truncus coeliacus, is the first major branch of the abdominal aorta. It is about 1.25 cm in length. Branching from the aorta at thoracic vertebra 12 (T12) in humans, it is one of three anterior/ midline branches of the abdominal aorta.

<span class="mw-page-title-main">Superior mesenteric artery</span> Artery which supplies blood to the intestines and pancreas

In human anatomy, the superior mesenteric artery (SMA) is an artery which arises from the anterior surface of the abdominal aorta, just inferior to the origin of the celiac trunk, and supplies blood to the intestine from the lower part of the duodenum through two-thirds of the transverse colon, as well as the pancreas.

<span class="mw-page-title-main">Gastroduodenal artery</span>

In anatomy, the gastroduodenal artery is a small blood vessel in the abdomen. It supplies blood directly to the pylorus and proximal part of the duodenum. It also indirectly supplies the pancreatic head.

<span class="mw-page-title-main">Midgut</span> Embryonic structure from which most of the human intestines develop

The midgut is the portion of the human embryo from which most of the intestines develop. After it bends around the superior mesenteric artery, it is called the "midgut loop". It comprises the portion of the alimentary canal from the end of the foregut at the opening of the bile duct to the hindgut, about two-thirds of the way through the transverse colon.

<span class="mw-page-title-main">Duodenojejunal flexure</span> Border between the duodenum and the jejunum

The duodenojejunal flexure or duodenojejunal junction, also known as the angle of Treitz, is the border between the duodenum and the jejunum.

<span class="mw-page-title-main">Ladd's bands</span>

Ladd's bands, sometimes called bands of Ladd, are fibrous stalks of peritoneal tissue that attach the cecum to the retroperitoneum in the right lower quadrant (RLQ). Obstructing Ladd's Bands are associated with malrotation of the intestine, a developmental disorder in which the cecum is found in the right upper quadrant (RUQ), instead of its normal anatomical position in the RLQ. Ladd's bands then pass over the second part of the duodenum, causing extrinsic compression and obstruction. This clinically manifests as poor feeding and bilious vomiting in neonates. Screening can be performed with an upper GI series. The most severe complication of malrotation is midgut volvulus, in which the mesenteric base twists around the superior mesenteric artery, compromising intestinal perfusion, leading to bowel necrosis.

<span class="mw-page-title-main">Outline of human anatomy</span> Overview of and topical guide to human anatomy

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<span class="mw-page-title-main">Superior mesenteric artery syndrome</span> Medical condition

Superior mesenteric artery (SMA) syndrome is a gastro-vascular disorder in which the third and final portion of the duodenum is compressed between the abdominal aorta (AA) and the overlying superior mesenteric artery. This rare, potentially life-threatening syndrome is typically caused by an angle of 6–25° between the AA and the SMA, in comparison to the normal range of 38–56°, due to a lack of retroperitoneal and visceral fat. In addition, the aortomesenteric distance is 2–8 millimeters, as opposed to the typical 10–20. However, a narrow SMA angle alone is not enough to make a diagnosis, because patients with a low BMI, most notably children, have been known to have a narrow SMA angle with no symptoms of SMA syndrome.

<span class="mw-page-title-main">Gastrointestinal wall</span> Digestive system structure

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  1. Mucosa
  2. Submucosa
  3. Muscular layer
  4. Serosa or adventitia
<span class="mw-page-title-main">Human digestive system</span> Digestive system in humans

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References

  1. 1 2 3 4 5 6 7 Meyers, M. A. (September 1995). "Treitz redux: the ligament of Treitz revisited". Abdominal Imaging. 20 (5): 421–424. doi:10.1007/BF01213262. PMID   7580775. S2CID   4381790.
  2. ↑ David A. Warrell (2005). Oxford textbook of medicine: Sections 18-33. Oxford University Press. ISBN   978-0-19-856978-7 . Retrieved 1 July 2010.: 511 
  3. 1 2 3 Mitra, S (2006). Anatomy, Combined Edition. Academic Publishers. p. 48. ISBN   81-87504-95-1.
  4. 1 2 3 4 Kim, Seuk Ky; Cho, C. D.; Wojtowycz, Andrij R. (25 July 2007). "The ligament of Treitz (the suspensory ligament of the Duodenum): anatomic and radiographic correlation". Abdominal Imaging. 33 (4): 395–397. doi:10.1007/s00261-007-9284-3. PMID   17653583. S2CID   11858260.
  5. ↑ Moore KL, Dalley AF, Agur AMR (2010). Clinically Oriented Anatomy (6th ed.). Lippincott Williams & Wilkins. p. 241. ISBN   978-0-7817-7525-0.
  6. ↑ Vernava, Anthony M.; Moore, Beth A.; Longo, Walter E.; Johnson, Frank E. (July 1997). "Lower gastrointestinal bleeding". Diseases of the Colon & Rectum. 40 (7): 846–858. doi:10.1007/BF02055445. PMID   9221865. S2CID   6971032.
  7. ↑ Gagner, Michel; Palermo, Mariano (28 July 2009). "Laparoscopic Whipple procedure: review of the literature". Journal of Hepato-Biliary-Pancreatic Surgery. 16 (6): 726–730. doi:10.1007/s00534-009-0142-2. PMID   19636494.
  8. ↑ Lee, Tae Hee; Lee, Joon Seong; Jo, Yunju; Park, Kyung Sik; Cheon, Jae Hee; Kim, Yong Sung; Jang, Jae Young; Kang, Young Woo (18 October 2012). "Superior Mesenteric Artery Syndrome: Where Do We Stand Today?". Journal of Gastrointestinal Surgery. 16 (12): 2203–2211. doi:10.1007/s11605-012-2049-5. PMID   23076975. S2CID   40701151.

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