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Colonic Volvulus

Laurence F. Yee, MD, FACS, FASCRS
Vice Chairman, Department of Surgery
California Pacific Medical Center
Assistant Clinical Professor of Surgery
University of California, San Francisco


Colonic volvulus is a twisting of a segment of colon resulting in an obstruction and sometimes ischemia.  The sigmoid colon and the cecum are the areas most commonly involved, but volvulus of the transverse colon and splenic flexure can occur.  The axial rotation of the volvulus can range from 180 to 540 degrees.  Regardless of the location, volvulus is manifested by progressive bowel distention proximal to the twisted colon.  Over time, peristalsis can force stool and gas into the closed loop.  As this closed loop distends, luminal pressure can increase beyond diastolic venous pressure.  This venous congestion, coupled with diminished arterial flow from mesenteric torsion, can lead to ischemia, gangrene, and perforation of the colon.  


Volvulus can occur in people who have a congenital or acquired mobile colonic segment that can twist on its mesentery.  Sigmoid volvulus typically occurs in people with a redundant sigmoid colon with a narrow mesentery.  Cecal volvulus occurs in people with a mobile cecum and right colon that is not fixed to the parietal peritoneum and retroperitoneum.  Although sigmoid and cecal volvulus share some features, their presentation and treatments are quite different so they will be discussed individually.  

Sigmoid Volvulus  


Despite its seeming rarity, sigmoid volvulus is the third leading cause of colonic obstruction after cancer and diverticulitis in the United States , representing 2%-5% of all large bowel obstructions (1,2).  It is much more common in other parts of the world, representing up to 50% of all colon obstructions in some countries (3).  

Risk factors           

Advancing age 

Although sigmoid volvulus has been described in virtually all ages, advancing age appears to be one of the strongest risk factors.  In the United States , the average age for the presentation of sigmoid volvulus is between 62 to 72 years (6).  It is postulated that as one ages, chronic constipation and colonic distention contribute to the elongation of the sigmoid colon and subsequent higher risk of volvulus over time (5).  When the very rare case of sigmoid volvulus occurs in children, factors leading to an early elongation of the sigmoid colon, such as Hirschsprung’s disease, megacolon, cystic fibrosis, chronic constipation, and congenital malformations, must be considered (7).   

Neurologic and psychiatric disease

In the United States (US) and the United Kingdom (UK), 40% to 45% of all patients with sigmoid volvulus are from psychiatric institutions or nursing homes (8,9).  It is thought that institutionalized patients with neurologic or psychiatric diseases such as Parkinson’s disease, spinal cord disease, and schizophrenia have decreased peristalsis and increased colonic distention due, in part, to immobility.  Neurologic and psychotropic medications can also contribute to altered colonic motility.  This can result in the elongation of the sigmoid colon, making these patients particularly vulnerable to the development of sigmoid volvulus (1,8).  


Outside of the US and UK , sigmoid volvulus is quite common.  The “volvulus belt” includes Africa, India , Iran , Russia , and Brazil where 30% to 80% of large bowel obstructions are due to sigmoid volvulus (9).  The majority of those affected are males between ages 40 to 51 (9).  In the US , African Americans have a 2:1 higher risk of developing sigmoid volvulus than Caucasian Americans (6).  It is largely unknown why these geographic and ethnic differences exist in the risk of developing sigmoid volvulus.  In Africa, India , and Iran , a high vegetable and fiber diet has been implicated in the development of a redundant colon, leading to sigmoid volvulus.  An interesting example exists in Brazil , where Chagas’ disease or trypanosomiasis is endemic causing degeneration of neurons in the myenteric plexus of the colon in affected individuals.  As the disease progresses, megacolon can result, ultimately leading to a 27% risk of developing sigmoid volvulus.  In the Bolivian Andes, high altitude is thought to increase intra-colonic pressures leading to a higher incidence of sigmoid volvulus.  Thus, higher dietary fiber, higher altitude, toxins, and motility disorders may all play roles in the worldwide geographic distribution of sigmoid volvulus (10).   


Worldwide, twice as many men than women develop sigmoid volvulus (6).  This gender difference has been attributed to the wider, more relaxed female pelvis allowing for spontaneous reduction of a sigmoid volvulus.  Furthermore, other studies have found that males have taller and thinner sigmoid mesenteries than females, resulting in a male predisposition for axial rotation of the sigmoid colon.  


After adhesions, sigmoid volvulus is the second most common cause of intestinal obstruction in pregnancy, comprising 25% to 44% of all cases (6).  It is postulated that during pregnancy, the enlarging uterus can displace a redundant sigmoid colon out of the pelvis, sometimes resulting in a twisting of the colon (6).  As a result, the majority (75%) of these occur during the third trimester.  The abdominal distention and constipation related to pregnancy combined with a general reluctance to perform x-rays in pregnant women often lead to a delay in diagnosis of sigmoid volvulus.    


Clinical Manifestations 

The majority of patients with sigmoid volvulus present with acute or chronic symptoms of abdominal pain, distention, and obstipation.  Typically, patients will have 3 to 4 days of symptoms before presenting to the hospital (20).  Approximately 50% of patients will report having a previous, similar attack (6).  Nausea and vomiting can occur late with progressive distention.  Physical exam findings include a distended, tympanitic abdomen and an empty rectum on digital examination.  In institutionalized and elderly patients with sigmoid volvulus, presentation to the hospital is often delayed and accurate history-taking can be challenging.  The differential diagnosis for these non-specific findings includes obstructing colon cancer, diverticulitis, mesenteric ischemia, pseudo-obstruction, and small bowel obstruction.  A more dramatic presentation of sigmoid volvulus is severe abdominal pain and shock from gangrene or perforation of the colon, necessitating immediate surgical laparotomy.  Fortunately, presentation with gangrene occurs in only 10% to 20% of patients.

Radiographic studies

A plain upright abdominal film can suggest the diagnosis of sigmoid volvulus in approximately 60% to 70% of cases.  A dilated, gas-filled, ahaustral, sigmoid colon extending from the pelvis to the right upper quadrant creates the classic appearance of a “bent inner tube”.  This inverted U-shape of the dilated sigmoid colon has the limbs directed towards the pelvis.  The “coffee bean” sign represents edematous contiguous colonic walls forming a dense white line surrounded by the curved and gas-filled lumen.  The presence of free air is an ominous sign.  In 30% to 40% of patients, plain films will not be diagnostic of volvulus, and may suggest a large bowel obstruction or a giant sigmoid diverticulum.

A single-contrast barium or hypaque enema can be performed if the diagnosis is in doubt.  It can demonstrate the typical “bird’s beak” or “ace of spades” appearance of the completely obstructed sigmoid volvulus.  This test is contraindicated when gangrenous bowel is suspected or pneumoperitoneum is seen on plain abdominal films.  Furthermore, although this test can be diagnostic, it is unlikely to reduce the volvulus and perforations by excessive pressure have been reported.

CT scan of the abdomen and pelvis is usually confirmatory of a suspected sigmoid volvulus.  The presence of the “whirl sign” of the twisted mesentery with a dilated sigmoid colon is diagnostic of sigmoid volvulus.  CT scan can also demonstrate signs of ischemia such as mural thickening and mesenteric edema.  Grave prognostic signs of CT scan include intramural or portal venous gas and free air and fluid in the peritoneal cavity.  With the liberal usage of CT scan by emergency physicians and recent technical improvements in speed and imaging, most patients today will have a CT scan confirming the presence of sigmoid volvulus. An additional advantage of CT scan is its ability to determine the cause of abdominal pain if the source is not sigmoid volvulus.


Volume resuscitation

The ideal treatment of sigmoid volvulus includes the relief of the colonic obstruction and the prevention of subsequent attacks.  The initial goal of treatment for sigmoid volvulus is volume resuscitation as these patients are usually substantially dehydrated.   Placement of a nasogastric tube may be useful to prevent aspiration.  This is done in preparation for possible sigmoidoscopy and/or surgical treatment.

Sigmoidoscopic decompression 

If the patient with sigmoid volvulus does not have peritonitis or suspected gangrene, reduction by sigmoidoscopy should be attempted.  Sigmoidoscopy can detorse the twisted sigmoid colon, assess the colon for viability, and reduce the colonic distention.  Endoscopically, the area of twisting is identified as a spiraling, narrow area of colon at 15 to 25 cm from the anal verge.  The endoscope is slowly and gently advanced through this tight narrowing, usually resulting in a straightening of the twisted colon.  An area of dilated, gas-filled colon is typically encountered, demonstrating the mucosa of the “closed loop”.   Viability of the mucosa can be assessed and proximal decompression can be performed.  Placement of a rectal tube beyond the point of obstruction for 48 to 72 hours can allow for further decompression, facilitate colonic cleansing, and temporarily prevent recurrent volvulus.  If the volvulus cannot be reduced endoscopically or there are signs of mucosal ischemia, immediate surgery is indicated.  Overall, sigmoidoscopic reduction and decompression of sigmoid volvulus is successful in 70% to 90% of cases (4,10).  Definitive surgical treatment of sigmoid volvulus is recommended soon after successful decompression because of the high spontaneous recurrence rate of 70% combined with the unpredictable time to recurrence (average 3 months) (4,11,20).  Exceptions to this recommendation include pregnant women in their early trimesters when detorsion alone may allow them to progress to a later trimester or full term, when the miscarriage rate is lower and surgery is safer for the mother.

Sigmoid colectomy for gangrenous volvulus

Patients with an acute abdomen or suspected gangrene from sigmoid volvulus should undergo immediate laparotomy.  In this emergency situation, a long midline incision may be necessary to accommodate the distended sigmoid colon through the wound to prevent rupture of the gas-filled, gangrenous colonic segment.  Sigmoid colectomy is performed and resection margins are based on viability of the colon.  Gangrene can occur at the neck of the volvulus, the twisted sigmoid loop, or the distal sigmoid or upper rectum from retrograde mesenteric thrombosis (1).  Whether or not an intraoperative colonic lavage and/or diverting stoma are performed after sigmoid colectomy is case and surgeon dependent.  If the patient is institutionalized, immobilized, or incontinent, creation of a stoma may be prudent.  Despite immediate colectomy, the mortality rate with gangrenous sigmoid volvulus is still 31% to 52% (4). 

Sigmoid colectomy after colonoscopic decompression

After successful colonoscopic detorsion and decompression of a non-ischemic sigmoid volvulus, a thorough resuscitation and full bowel preparation can be accomplished.  In the majority of these cases, a semi-elective sigmoid colectomy can be performed safely without the need for a stoma.  The operation is usually not technically difficult or time-consuming since the sigmoid colon is mobile and a wide mesenteric resection is not required.  Minimal proximal, lateral, or medial mobilization is needed to resect the sigmoid colon for volvulus.  Because of this favorable surgical anatomy, some advocate a mini-laparotomy or a laparoscopic approach to sigmoid colectomy for volvulus, conferring the added advantages of smaller incisions, less pain, and faster recovery (12-14).  Whether it is performed open or laparoscopically, sigmoid colectomy after colonoscopic reduction remains the “gold standard” of treatment for non-ischemic sigmoid volvulus.  The mortality from resection of viable sigmoid colon in this setting is 6% to 12% with a recurrence rate of 1% to 4% (4).  An exception to this recommendation is sigmoid volvulus in the setting of megacolon, where the recurrence rate after sigmoid colectomy is high as 36% to 66% (15).  Because of this high risk of recurrence, a subtotal colectomy in the setting of megacolon should be considered (15). 

Non-resectional techniques for sigmoid volvulus

Because of the morbidity and mortality associated with sigmoid resection for volvulus, several non-resectional approaches have been proposed.  All of these techniques are designed to prevent recurrent twisting of the colon without resection or colotomy. The majority of these non-resectional techniques have been applied to high risk or elderly patients who are poor surgical candidates.  Sigmoidopexy using sutures, Gore-Tex strips, or extraperitonealization to anchor the redundant sigmoid colon have been described with mortality rates of 11% and recurrence rates of 22%.  The application of laparoscopic techniques to perform sigmoidopexy has been advocated in patients with chronic sigmoid volvulus (16).  A novel technique utilizes T-fasteners to fix the colon to the anterior abdominal wall using colonoscopic guidance, similar to the technique of percutaneous endoscopic gastrostomy tube placement.  Other techniques employ staples to perform laparoscopic or endoscopic sigmoidopexy.  Finally, mesosigmoidoplasty, a surgical technique of preventing twisting by broadening the sigmoid mesentery has been advocated.  These intriguing, minimally invasive, non-resectional techniques can substantially reduce pain, risk of infection, and morbidity, however, their recurrence rates and durability are still unproven. 

Cecal Volvulus


In the US , cecal volvulus represents approximately 40% of all colonic volvulus, second only to sigmoid volvulus (50%).   Two types of cecal volvulus can occur.  In axial cecal volvulus (90%), the right colon and small bowel typically rotate counterclockwise around the mesentery and ileocolic artery, resulting in an obstruction.  In cecal bascule (10%), the mobile cecum folds horizontally upwards, resulting in a colonic obstruction.  Both of these types require a mobile cecum and right colon to occur.  It is postulated that this mobility is congenital: a result of a failure of developmental fusion of the mesentery of the right colon with the posterior parietal peritoneum (6).  Some autopsy studies have suggested that 10% to 25% of the population have a cecum mobile enough to develop volvulus or a bascule (17).  Given this anatomic prevalence, it is unknown why cecal volvulus does not occur more frequently than is clinically observed.

Risk Factors

Because of its congenital predisposition, advanced age is not a significant risk factor in developing cecal volvulus.  In the US , the mean age for cecal volvulus is 53 years, much younger than that seen for sigmoid volvulus (6).  In other parts of the world, the age is even younger; a study from India found a mean age of 33 years for cecal volvulus.  However, unlike sigmoid volvulus, there are no definite geographic or ethnic risk factors known, and females may be slightly more likely than men to develop cecal volvulus (18).  Potential risk factors for the development of cecal volvulus include adhesions from previous surgery, colonic atony, pregnancy, post colonoscopy, and distal colonic obstruction.


Clinical Presentation

Patients with cecal volvulus can present with a variable duration of symptoms, from 2 hours to 10 days, with an average of 2 days (18).  Most present with a gradual onset of abdominal pain, cramping, distention, obstipation, and vomiting, similar to the symptoms for a distal small bowel obstruction.  Physical examination may reveal an asymmetrically distended abdomen with tympany in the mid-abdomen or left upper quadrant.  Others, however, can present a sudden onset of severe abdominal pain and distention, signifying acute vascular compromise.  As cecal volvulus usually affects a younger population, appendicitis, ruptured ovarian cyst, urinary tract infection, cecal diverticulitis, inflammatory bowel disease, and small bowel obstruction are included in the differential diagnosis.  These presentations generally lead to a radiographic evaluation.

Radiographic studies

In cecal volvulus, a plain, upright abdominal film can demonstrate the classic appearance of the “comma” or “coffee bean” shaped dilated cecum with an air-fluid level seen.  The dilated cecum is usually displaced medially and superiorly.  Unfortunately, this appearance is present in only 25% of cases.  A decompressed distal colon and dilated small bowel may be present.  Plain films of cecal volvulus can be confused with gastric distention, small bowel obstruction, and sigmoid volvulus.  Cecal bascule can demonstrate similar findings with a more central position of the dilated cecum.  Usually further radiographic studies are needed to confirm the diagnosis.

A single-contrast barium or hypaque enema can demonstrate a tapered or “bird’s beak” narrowing in the right colon, confirming a cecal volvulus.  In cecal bascule, the termination of contrast is rounded as a result of the transversely folded cecum.  These retrograde studies are contraindicated when gangrenous bowel is suspected or pneumoperitoneum is seen on plain abdominal films.  In addition, because the obstruction is in the right colon, this examination can be particularly uncomfortable and gentle instillation of contrast is recommended to avoid perforation.

Many patients with cecal volvulus will undergo a CT scan in the workup of their abdominal pain.  CT scan is typically diagnostic, demonstrating a massively dilated cecum with associated small bowel dilation.  The twisted or “whirl” mesenteric configuration around the ileocolic artery is pathognomonic of axial cecal volvulus.  In cecal bascule, CT scan can show the cecum folding upward resulting in obstruction, without the twist in the mesentery.  Similar to sigmoid volvulus, CT scan can also demonstrate signs of colonic or small bowel ischemia such as mural thickening and mesenteric edema.  Overall, radiographic studies confirm the diagnosis of cecal volvulus 90% of the time.  The remainder are diagnosed at surgery.

Treatment of Cecal Volvulus

Colonoscopic decompression of cecal volvulus is not recommended

Unlike sigmoid volvulus, colonoscopic detorsion of cecal volvulus is technically difficult and is associated with high failure and perforation rates.  In addition, gangrenous cecal volvulus is present 20% to 25% of the time.  Thus, surgical intervention is advised as soon as the diagnosis is made, and attempts to detorse a cecal volvulus is not recommended.

Right hemicolectomy for gangrenous cecal volvulus

At surgery, the initial step is to determine the viability of the colon and terminal ileum.  If the bowel is gangrenous, right hemicolectomy is performed without untwisting the mesentery.  Avoidance of untwisting the gangrenous cecum is important in order to prevent reperfusion bacteremia and subsequent sepsis.  Resection of all gangrenous bowel may involve a substantial portion of the terminal ileum.  Depending on the patient’s condition, a primary anastomosis or ileostomy can be performed.  Rapid diagnosis, resuscitation, and surgery are imperative as the mortality in gangrenous cecal volvulus is 17% to 40%.

Right hemicolectomy for non-gangrenous cecal volvulus

If the colon is viable at laparotomy, operative detorsion can be performed, usually in a clockwise fashion.  Detorsion without resection is not advised as it is associated with a high recurrence rate (75%).  Right hemicolectomy is the gold standard as it removes the mobile cecum and prevents future recurrences.  This can be performed by either an open or laparoscopic approach.  In most instances, a primary ileo-transverse colonic anastomosis can be performed safely.  If the patient is greatly distended from proximal small bowel dilation, the laparoscopic approach is not recommended due to the lack of operative working space.  Recurrence rate of cecal volvulus after right hemicolectomy is essentially zero, however, the mortality rate after resection remains 9% to 18%.

Non-resectional techniques for cecal volvulus

For non-gangrenous cecal volvulus several non-resectional techniques have been proposed.  Cecostomy is performed by placing a tube in the cecum and bringing it out through the abdominal wall.  This secures the cecum in place, preventing recurrent twisting, and allows decompression of the dilated right colon.  Cecostomy has the advantage of avoiding the risks of resection and anastomosis.  The cecostomy tube is ultimately removed and surgical adhesions are thought to secure the cecum to the right lower quadrant.  Some have advocated the addition of cecopexy for more definitive fixation.  However, the technical aspects of placing a tube and sutures in a thin walled, dilated cecum can be difficult and unsatisfying.  Furthermore, ongoing contamination from the cecostomy tube can occur and is associated with a high incidence of wound infection, fecal fistula, and intraperitoneal contamination.  Although the recurrence rate for cecostomy is low (2% to 14%), it is associated with a substantial mortality rate (0% to 33%).

Another non-resectional alternative for cecal volvulus is cecopexy.  Cecopexy is performed by fixing the right colon to the right parietal peritoneum and retroperitoneum, most commonly by sutures.  A long peritoneal flap originating from the right paracolic gutter can be used to anchor the right colon and cecum to the right lower quadrant, preventing recurrent twisting.  However, like cecostomy, placing sutures in a dilated, thin-walled cecum can be technically challenging.  Nonetheless, cecopexy is an attractive option by avoiding resection or colotomy, decreasing infection rates and morbidity.  The laparoscopic approach to cecopexy has the added advantage of small incisions and may be beneficial in selected patients (19).  Overall, cecopexy has a lower mortality rate than either right hemicolectomy or cecostomy (0% to 14%), but has a higher recurrence rate of 13% to 28%.  Perhaps as surgical technique and instrumentation evolve and improve, the recurrence rate after cecopexy can be reduced to where it would be the procedure of choice for non-gangrenous cecal volvulus.

Transverse Colon and Splenic Flexure Volvulus, and Ileosigmoid Knotting

Volvulus of the transverse colon (4%) and splenic flexure (2%) comprise a small minority of colonic volvulus.  These patients have a mobile transverse colon or splenic flexure as a result of a congenital or acquired loss of colonic attachments, including the gastrocolic omentum, lienocolic, splenocolic, and phrenocolic ligaments.  Risk factors for the development of volvulus in these patients include distal colonic obstruction, chronic constipation, adhesions, and surgical mobilization of the omentum or colon.  Although treatment by colonoscopic reduction and transverse colopexy have been described, these rare entities are most commonly treated by extended right hemicolectomy for transverse colon volvulus and left colectomy for splenic flexure volvulus.  Lastly, ileosigmoid knotting is a very rare entity where the ileum wraps itself around the base of the sigmoid colon resulting in a colonic obstruction with a closed loop.  This condition is extremely rare in the US , and is reported primarily in Asia, Africa, and the Middle East .  Despite immediate surgery, gangrene is found in 75% of patients and is associated with an extremely high mortality rate (31%).


In the US , colonic volvulus is a relatively rare condition, but its incidence is likely to increase over the next 10 years as life expectancy increases and the ethnic mixture of our population changes.  Rapid diagnosis, resuscitation, and open surgical resection for colonic volvulus have been the mainstays of treatment for decades, yet the morbidity and mortality from surgery remain substantial.  Hopefully, further innovations in laparoscopy, endoscopy, surgical instrumentation, and pharmacology will yield new tools to enable surgeons to reduce the infection, pain, disability, recurrence rates, and mortality associated with colonic volvulus in the near future.


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