Volvulus

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: ; Hadeel Maksoud M.D.[2]

The pathophysiology and treatment of volvulus were established in the 20th century, by William Ladd. However, evidence for cases of volvulus go as far back as 1550 BC in Egypt.

The most important events considering volvulus historical perspective include:^[1][2][3]

• Cases of volvulus have been described as far back as 1550 B.C. in ancient Egypt.
• In the early 1800s, the decription of the pathophysiology of volvulus began with a “suspensary muscle” anchoring the duodenal-jejunal junction in the left upper quadrant by anatomist Václav Treitz.
• In 1836, Von Rokitansky described sigmoid volvulus.
• In 1883, Atherton described surgical laparotomy and lysis of adhesions for treatment of volvulus.
• In 1947, Brusgaard challenged Atherton by suggesting that decompression of the affected bowel can be achieved through sigmoidoscopy and placement of a rectal tube.
• In the 20th century, William Ladd a paediatric surgeon established the treatment of volvulus.

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

Volvulus can happen at various parts of the gastrointestinal tract. Volvulus can also occur congenitally or acquired in a newborn, an infant or an adult. These include sigmoid volvulus, cecal volvulus, gastric volvulus and ileal volvulus.

Please scroll down to view a full classification of Volvulus.^[1][2][3][4]

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

Regardless of cause, volvulus causes symptoms by two mechanisms: One is bowel obstruction, manifested as abdominal distension and vomiting. The other is ischemia (loss of blood flow) to the affected portion of intestine. This causes severe pain and progressive injury to the intestinal wall, with accumulation of gas and fluid in the portion of the bowel obstructed. Ultimately, this can result in necrosis of the affected intestinal wall, acidosis, and death. Acute volvulus therefore requires immediate surgical intervention to untwist the affected segment of bowel and possibly resect any unsalvageable portion.

• In western society, chronic constipation can lead to an overloaded sigmoid colon.
• In developing nations, a high fiber diet leads to sigmoidal overload.
• When the bowel loop is overloaded with material, it becomes susceptible to torsion along the axis of an elongated mesentery.
• A large pelvic mass or a large gravid uterus can alter the position of the intra-abdominal organs, predisposing to the formation of volvulus.
• With recurrent attacks of torsion, the base of the mesentery can become chronically inflammed and eventually shortens.
• This leads to recurrent volvulus.
• The twisting of a mobile loop of bowel can happen spontaneously and may be congenital or acquired.
• Acquired causes of volvulus include:^[1][2][3]
  • Adhesions
  • Iatrogenic e.g. lower GI endoscopy
  • Bowel atony
  • Hirschsprung’s disease
  • Pregnancy
• Congenital causes are discussed below.

• Malrotation occurs when there is arrest of the normal rotation of the embryonic gut.^[4][5]
• During weeks 4-8 of development, the embryonic coelom, or cavity, normally cannot accommodate the rapidly expanding gastrointestinal (GI) tract.
• Consequently, the primary intestinal loop pushes back into the yolk stalk, and will become the future umbilicus.
• The direction in which the loop grows takes the axis of the future superior mesenteric artery.
• As the primary intestinal loop grows out of the abdomen, it begins to rotate by twisting 90 degrees counterclockwise.
• There are two factors that force this rotation:
  • The proximal bowel (gastroduodenal) grows faster than the distal bowel (cecocolic).
  • The liver has rapidly develops.
• During weeks 8 – 10, the primary intestinal loop continues to grow and returns back into the abdomen cavity and a further 180 degree counterclockwise rotation occurs.
• Overall, the primary loop twists a total of 270 degrees in a counterclockwise direction.
• Once the primary loop is in its final position, fixation to the posterior abdominal wall begins.
• The proximal bowel portion including the stomach and duodenum are fixated early in gestation through the ligament of Treitz.
• The colon takes a longer time to become fixated and usually, fixation is completed near term.

• Normal gut development means that:^[6]
  • A wide-based mesentery will extend from the ligament of Treitz in the left upper quadrant to the ileocecal valve in the right lower quadrant.
  • The primary loop will continue its rotation upon return to the abdominal cavity.
  • Both proximal (duodenojejunal) and distal (cecocolic) limbs rotate at the same rate and to the same degree.
• Congenital volvulus happens when the following anomalies have occurred:
  • Narrow mesenteric base:
    • The midgut becomes suspended by a narrow pedicle.
  • Non-rotation:
    • In non-rotation, the primary loop undergoes no further rotation during its return to the abdominal cavity.
    • The small bowel becomes located on the right whilst the colon is on the left of the abdomen.
    • Non-rotation is less dangerous than malrotation because in non-rotation, the mesentery is wider and the risk of volvulus is lower.
  • Malrotation:
    • In malrotation, the proximal (duodenojejunal) limb remains in a position of non-rotation, and the distal (cecocolic) limb partially rotates (usually only 90 degrees instead of 180 degrees).
    • Consequently,the cecum is relocated to the mid-upper abdomen, instead of the right lower quadrant.
    • The abnormally-positioned cecum is attached by bands of peritoneum (Ladd bands) to the right lateral abdominal wall.
    • Ladd bands can cause compression and obstruction of the duodenum extrinsically.

• Other anomalies of rotation can rarely occur, these include:
  • Rotation of the proximal (duodenojejunal) limb is reversed resulting in a duodenum that is located anterior to the superior mesenteric artery.
  • Rotation of the distal (cecocolic) limb is reversed resulting in a transverse colon that is located posterior to the superior mesenteric artery.
  • Finally, a combination of reversed rotation of the proximal (duodenojejunal) limb with normal rotation of the distal (cecocolic) limb can lead to a paraduodenal hernia.
    • In this anomaly, anterior to the superior mesenteric artery lies the duodenum. Anterior to the duodenum, the distal (cecocolic) limb rotates normally.
    • The mesentery of the right colon creates a pouch, the small bowel then herniates into it.

• The mesentery anchors the ileum and sigmoid colon to the posterior abdominal wall.^[7][8]
• An air filled loop of the sigmoid colon or the terminal ileum, sometimes, twists itself about the axis of the mesentery.
• The incidence of volvulus occurring increases with a redundant or longer than normal mesentery.
• If the degree of twisting is beyond 180 – 360 degress, then the bowel loop will become obstructed and ischemia will develop.
• Ileosigmoid knotting is a variant of sigmoid volvulus where the ileum wraps around the sigmoid in a clockwise direction.

• Normally, there are ligaments such as the gastrocolic, gastrohepatic, gastrosplenic and gastrophrenic ligaments that keeps the stomach in place by attaching it to other abdominal organs and the diaphragm.^[9][10]
• However, the stomach can twist around its horizontal or vertical axis.
• Gastric outlet obstruction may occur as a result of abnormal rotation more than 180 degrees.
• Chronic rotation can cause bleeding by decreasing venous return and increasing capillary pressure.

• The cecum is especially liable to being mobile congenitally.^[11][12][13]
  • The cecum becomes mobile when failure of the ascending colon mesentery to fuse with the posterior parietal peritoneum occurs.
  • Autopsy studies have shown that about 10-25% of the population have a mobile cecum and ascending colon sufficient to develop a volvulus.
  • A congenital mobile cecum can also cause mobile cecum syndrome.
• There are three types of cecal volvulus, type I and II are the most common, type III accounts for the remaining 20% of cases:
  • Type I – organoaxial:
    • The cecum twists in a clockwise manner along its axis.
    • The cecum fills with air and remains in right lower quadrant.
  • Type II – organoaxial:
    • The cecum and a proximal part of the ileum twist in a counterclockwise direction.
    • The cecum becomes inverted and is relocated to the left lower quadrant.
  • Type III – mesentericoaxial:
    • The cecum folds upwards and back on itself rather than rotating along its axis.

Several genetic and chromosomal mutations have been implicated in causing intestinal malrotation and other gastrointestinal abnormalities that may later be complicated by volvulus.

• The forkhead box transcription factor Foxf1 plays a role in normal division and attachments of organs in the gastrointestinal tract.
  • Then Foxf1 is knocked out in mice, it was found that somatic and splanchnic layers remain fused or incompletely separated.
  • Ultimately, this leads to an inability of the dorsal mesentery to tilt to the left.
• Pitx2 and Isl1 mutations lead to asymmetry of the gastrointestinal organs, attachments and rotations.
• Mutations in beta2 and beta4 subunits of the neuronal nicotinic acetylcholine receptor have been associated with a MMIH syndrome (megacystis, microcolon and intestinal hypoperistalsis)

• Deletions at chromosome 16q24.1 are associated with a number of GI tract abnormalities including malrotation and other abnormalities that result in:
  • Reduced life expectancy
  • Restricted growth
  • Dysmorphic facial features
  • Learning disability, if the child survives.
• Deletions of the long arm of chromosome 13 are associated with Hirschsprung disease and other GI tract malformations: malrotation, jejunal and ileal atresia, agenesis of mesentery and hypoplastic gallbladder.
• Heterozygous mutations in EDNRB (endothelin receptor type B) gene, which is found within the deleted interval, results in Hirschsprung disease, but other GI tract malformations have not been reported in conjunction with EDNRB mutations.

On gross pathology, a distended, air-filled bowel twisted around its mesentery with or without ischemia, necrosis and/or gangrene are characteristic findings of volvulus.

On microscopic histopathological analysis, thrombi, inflammatory cells, and necrotic changes are characteristic findings of volvulus.

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

Midgut volvulus occurs in patients (usually in infants) that are predisposed because of congenital intestinal malrotation. Segmental volvulus occurs in patients of any age, usually with a predisposition because of abnormal intestinal contents (e.g. meconium ileus) or adhesions. Volvulus of the cecum, transverse colon, or sigmoid colon occurs, usually in adults, with only minor predisposing factors such as redundant (excess, inadequately supported) intestinal tissue and constipation.

Causes of volvulus can either be congenital or acquired:

• Acquired causes of volvulus include:^[1][2][3]
  • Adhesions
  • Iatrogenic e.g. lower GI endoscopy
  • Bowel atony
  • Pregnancy
  • Crohn’s disease
  • Chagas disease
  • Age more than 50 years old
  • Chronic constipation
  • Dilated colon
  • Colonic dysmotility
  • Laxative dependence
  • Crohn’s disease
  • Chagas disease
  • Phrenic nerve paralysis
• Congenital causes of volvulus include:^[4]
  • Hirschsprung’s disease
  • Paraesophageal hernia
  • Hiatal hernia
  • Diaphragm eventration
  • Kyphoscoliosis
  • Narrow mesenteric base
    • The midgut becomes suspended by a narrow pedicle.
  • Non-rotation
    • In non-rotation, the primary loop undergoes no further rotation during its return to the abdominal cavity.
    • The small bowel becomes located on the right whilst the colon is on the left of the abdomen.
    • Non-rotation is less dangerous than malrotation because in non-rotation, the mesentery is wider and the risk of volvulus is lower.
  • Malrotation
    • In malrotation, the proximal (duodenojejunal) limb remains in a position of non-rotation, and the distal (cecocolic) limb partially rotates (usually only 90 degrees instead of 180 degrees).

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: ; Hadeel Maksoud M.D.[2]

Volvulus must be distinguished from other diseases, as it may be a solitary finding or a feature of another disease. Differential diagnoses include: Crohn’s disease, necrotizing enterocolitis, duodenal atresia, pyloric stenosis, toxic megacolon and pseudocolonic obstruction (Ogilvie syndrome).

The following are differential diagnoses for volvulus:^[1]

• Crohn’s disease
• Necrotizing enterocolitis
• Duodenal atresia
• Pyloric stenosis
• Gastroenteritis
• Superior mesenteric artery syndrome
• Gastroesophageal reflux
• Ulcerative colitis
• Toxic megacolon
• Pseudocolonic obstruction (Ogilvie syndrome)

A table with the differential diagnoses for volvulus is discussed below:

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: ; Hadeel Maksoud M.D.[2]

Acute mechanical small bowel obstruction is a common surgical emergency where volvulus is the cause in 10% of cases. It is estimated that over 300,000 laparotomies are performed per year in the United States for adhesion-related obstructions such as volvulus. Volvulus originating in the colon is the third most common cause of large bowel obstruction.

• The incidence of volvulus is approximately 2 per 100,000 individuals worldwide.^{[1][2][3][4][5]}
• Sigmoid volvulus has the highest incidence, followed by cecal volvulus.
• The incidence of cecal volvulus increases per year, whereas the incidence of sigmoid volvulus remains stable.
• The incidence of volvulus is higher in those that live in nursing homes or are institutionalized. These patients usually take psychotropic drugs that interfere with colonic motility and can increase the incidence of volvulus.
• The incidence of gastric volvulus is rare.

• In 2002 – 2010, the prevalence of colonic volvulus is estimated to be 63,749 cases in the United States annually.^[4]

• The mortality rate of volvulus is 7 per 100 cases.^[3]

• The incidence of volvulus increases with age; the median age at diagnosis is 70 years.^[4][6][5]
• Sigmoid volvulus has been reported in children and adolescents and is usually associated with abnormal colonic peristalsis.
• Gastric volvulus is rare and the incidence peaks after the fifth decade.
• The incidence of neonatal and infantile volvulus is unknown since non-rotation or malrotation of the gut may remain asymptomatic throughout life.^[7]
  • In the United States, non-rotation is an incidental finding in 2 out of 1000 upper gastrointestinal contrast studies.
  • In the United States, symptomatic malrotation in neonates occurs in 1 in 6000 live births.

• Volvulus usually affects individuals of the Black race.^[8][9]
  • Black individuals are at increased risk for volvulus because they tend to have a longer mesentery and sigmoid colon.

• Most studies have found that volvulus affects men and women equally.^[10][11][12]
• Although some studies have found a predominance in men, cecal volvulus has been found to be more prevalent in younger females.

• The majority of volvulus cases are reported in Russia, India, Iran, Norway and Africa.^[3]
• In the United States, volvulus only accounts for 0.1 of cases with intestinal obstruction.

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

Common risk factors in the development of volvulus include pregnancy, chronic constipation, age over 50, and long sigmoid colon and mesentery.

Common risk factors in the development of volvulus include:^[1][2][3][4]

• Age more than 50 years old
• Intestinal malrotation
• Pregnancy
• Abdominal adhesions
• Chronic constipation

Less common risk factors in the development of volvulus include:

• Treatments for neuropsychiatric disorders lead to colonic dysmotility, such as:
  • Parkinson disease
  • Multiple sclerosis
  • Spinal cord injury
• Dilated colon
• Colonic dysmotility
• Long mesentery and sigmoid colon
• Laxative dependence
• Hirschsprung’s disease
• Crohn’s disease
• Chagas disease
• Paraesophageal hernia
• Hiatal hernia
• Diaphragm eventration
• Phrenic nerve paralysis
• Kyphoscoliosis

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

There is insufficient evidence to recommend routine screening for volvulus. However, there are screening programs in place that utilize an ultrasound to seek out intestinal malrotation, which may be a cause of fatal midgut volvulus.

There is insufficient evidence to recommend routine screening for volvulus. However, there are screening programs in place for intestinal malrotation which may be a cause of fatal migdut volvulus.^[1]

• Ultrasound is an effective screening tool in ruling out those children who may be at risk of intestinal malrotation – associated volvulus.

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Hadeel Maksoud M.D.[2]

If left untreated, the majority of patients with volvulus may progress to develop gangrene of the bowel, which can be fatal. Common complications of volvulus include bowel ischemia, gangrene, and necrosis. Prognosis is generally excellent, so long as the affected part of the bowel is resected or untwisted before ischemia occurs, usually within 48-72 hours. If necrosis of the affected bowel has already occurred then the prognosis is poor and may be fatal.

• The symptoms of volvulus include abdominal pain, constipation and inability to defecate or pass gas.^[1][2]
• The symptoms of volvulus typically develop in approximately 3 hours up to several days with an average of 40 days.
• If left untreated, the majority of patients with volvulus may progress to develop ischemia and gangrene of the bowel, which can be fatal. The minority of patients may have spontaneous reduction of the effected portion of the bowel.

• Common complications of volvulus include:
  • Bowel ischemia
  • Gangrene
  • Perforation
  • Secondary peritonitis
  • Short bowel syndrome

• Prognosis is generally excellent so long as the affected portion of the bowel is decompressed within 48-72 hours.
• If ischemia has led to necrosis of the bowel segment, then the prognosis is poor and may be life threatening.

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