What Is a Twisted Colon? Causes, Symptoms, & Treatment

A twisted colon, known medically as colonic volvulus, happens when a section of the large intestine rotates around the tissue that anchors it in place, cutting off blood flow and trapping stool and gas. The sigmoid colon and the cecum are the two segments most often affected. It is the third most common cause of large bowel obstruction worldwide and accounts for roughly 15 percent of large bowel obstructions in the United States. The condition ranges from a slow, grumbling problem that comes and goes to a surgical emergency that can kill bowel tissue within hours.

Where the Colon Twists and Why It Matters

The colon is loosely shaped like an inverted U. At each end of that U sit the two segments most vulnerable to twisting: the sigmoid colon, a short S-shaped loop in the lower left abdomen just before the rectum, and the cecum, the pouch-like beginning of the large intestine on the lower right side. Together these account for the vast majority of colonic volvulus cases.¹ In rarer instances the transverse colon or splenic flexure can twist, but those events are uncommon enough that most of the research and clinical guidance focuses on the sigmoid and the cecum.

The sigmoid type is by far the more frequent of the two. It tends to occur in older adults, particularly men, and is closely linked to chronic constipation, a long and redundant sigmoid loop, and conditions that slow gut motility. Cecal volvulus tends to affect a somewhat younger group and arises when the cecum and ascending colon are incompletely attached to the back wall of the abdominal cavity, a congenital anatomical variation that allows too much mobility.² These two types differ enough in who they affect, how they present, and how they are treated that surgeons essentially approach them as related but distinct problems.

Causes and Risk Factors

The twist itself is a mechanical event, but several underlying factors make it more likely. For sigmoid volvulus, the most important risk factor is a long, floppy sigmoid loop with a narrow base where its supporting tissue attaches. That narrow base acts like the pivot point of a propeller: the longer and heavier the loop, the easier it is for it to swing around. Chronic constipation enlarges and elongates the sigmoid over time, which is why populations with high-fiber diets and large stool volumes in parts of Africa, the Middle East, and Russia see far more sigmoid volvulus than Western countries do. In sub-Saharan Africa, volvulus accounts for anywhere from 9 to 56 percent of all mechanical intestinal obstructions.³

In Western countries the profile looks different. Sigmoid volvulus typically shows up in elderly, institutionalized, or neuropsychiatric patients who are sedentary, chronically constipated, and often on medications that slow the gut. Neurological conditions are a notable contributor. Parkinson’s disease, for example, frequently causes treatment-resistant constipation, and sigmoid volvulus develops more often in people with Parkinson’s than in the general population.⁴

Cecal volvulus has a different setup. Instead of a redundant loop created over decades of constipation, the problem starts with incomplete fixation of the cecum to the posterior abdominal wall. In some people the cecum never fully attaches during fetal development, leaving it free to flip or fold. When the cecum is mobile, a sudden change in intra-abdominal pressure from straining, heavy lifting, or even a colonoscopy prep can trigger the twist. Previous abdominal surgery that creates adhesions or alters the anatomy is another well-recognized trigger.²

Recognizing the Symptoms

Symptoms depend on how tightly the colon has twisted and how quickly blood supply is compromised. In a classic sigmoid volvulus, the onset is often surprisingly gradual. Many patients have had previous episodes of bloating and cramping that resolved on their own before the one that finally brings them to the hospital. The hallmark triad is abdominal distension, crampy pain concentrated in the lower abdomen, and an inability to pass stool or gas. Nausea and vomiting follow as the obstruction builds. In some people the abdomen becomes visibly asymmetric, with one side noticeably more swollen than the other.

Cecal volvulus tends to present more acutely. The pain is usually on the right side, and vomiting comes earlier because the obstruction is closer to the small intestine. Distension can still be dramatic, but the clinical picture more closely resembles a small-bowel obstruction than a classic large-bowel block. When blood flow to the twisted segment is completely cut off, the bowel starts to die. At that point the pain becomes constant and severe, the abdomen may feel rigid, and signs of systemic infection like fever, rapid heart rate, and falling blood pressure can appear. That transition from crampy intermittent pain to constant unrelenting pain is the red flag that tissue is dying and emergency surgery is needed.

How Doctors Confirm the Diagnosis

A plain abdominal X-ray is often the first imaging study, and in sigmoid volvulus it can be remarkably revealing. The massively dilated sigmoid loop creates a distinctive shape described as the “coffee bean sign,” an oval shadow with a central crease running through it. When present, this sign is considered essentially diagnostic of sigmoid volvulus.⁵ The coffee bean can be huge, sometimes filling the entire abdomen on the X-ray.

CT scanning adds another layer. It shows exactly where the twist is, whether the bowel wall is still receiving blood, and whether the tissue has started to die. One CT finding that has proven especially useful is the “dark torsion knot sign,” where the twisted point of the mesentery appears dark on contrast-enhanced scans. In one study, this sign and the presence of sepsis were the only two independent predictors of a complicated volvulus requiring emergency surgery.⁶ CT is also better at distinguishing volvulus from acute colonic pseudo-obstruction, a condition that mimics the same symptoms but involves no physical twist at all.⁷

Non-Surgical Treatment for Sigmoid Volvulus

When imaging suggests the bowel is still alive, the first-line treatment for sigmoid volvulus is endoscopic decompression. A flexible tube or colonoscope is carefully passed through the rectum and into the twisted loop. As the scope navigates past the twist, the colon unravels, trapped gas rushes out, and the distension collapses. A rectal tube is usually left in place afterward to keep the segment from re-twisting immediately.

A large review of 748 patients who underwent endoscopic decompression found the procedure succeeded in about 83 percent of cases where the bowel was viable. Mortality from the procedure itself was very low at 0.5 percent, and the complication rate was under 2 percent. Patients stayed in the hospital for an average of about 35 hours.⁸ By those numbers, endoscopic decompression is a quick, low-risk way to relieve the immediate crisis.

The catch is that decompression does not fix the underlying anatomy. The redundant sigmoid loop is still there, and the conditions that caused it to twist in the first place persist. This is where the story gets complicated, because what happens next varies enormously depending on the patient’s fitness for surgery.

The Recurrence Problem

Recurrence after successful endoscopic decompression is the central dilemma in managing sigmoid volvulus. The numbers paint a clear picture: without surgery to remove the redundant sigmoid, the twist comes back in the majority of patients. One study tracking patients who were treated with decompression alone found that 80 percent experienced recurrence, with a median gap of about 86 days between episodes.⁹ Another study found that while about 63 percent of conservatively treated patients were recurrence-free at three months, that dropped to just 24 percent by two years.¹⁰

Each recurrence carries its own risk of bowel death and emergency surgery under worse conditions than a planned elective operation. A small but striking study found that five of seven patients managed with colonoscopic decompression alone were readmitted with another volvulus, leading the researchers to argue that all patients should be considered for definitive surgery after the first successful decompression, regardless of how frail they seem.¹¹ In practice, many elderly or high-risk patients are never referred for surgery and end up cycling through repeated emergency decompressions, a pattern that carries its own cumulative toll.

Surgical Options for Sigmoid Volvulus

Definitive surgery for sigmoid volvulus means removing the redundant sigmoid segment entirely. The question is how to reconnect the bowel afterward. There are two main approaches: resection with primary anastomosis, where the two cut ends are joined back together in the same operation, and Hartmann’s procedure, where the rectal stump is closed off and the upstream end is brought out through the abdominal wall as a colostomy.

When the bowel is gangrenous, the decision is urgent and there is no room for decompression first. The dead segment must come out. In this scenario, surgeons have historically favored Hartmann’s procedure on the logic that connecting bowel ends in a contaminated, inflamed abdomen risks a dangerous leak. But a meta-analysis pooling data from multiple studies found that mortality after primary anastomosis was about 15 percent compared with about 19 percent after Hartmann’s procedure, and the difference was not statistically significant. Complication rates were also similar.¹² This has led many surgeons to offer primary anastomosis even for gangrenous cases in selected patients, sparing them the burden of living with a stoma.

A separate retrospective study of 102 patients confirmed that major complications like anastomosis leakage, prolonged inability of the bowel to restart, and wound infection did not differ significantly between the two approaches, though hospital stay was slightly shorter in the Hartmann’s group during the initial admission.¹³ The trade-off is that Hartmann’s procedure often requires a second operation months later to reverse the stoma, adding its own risks and recovery period.

Treating Cecal Volvulus

Cecal volvulus is a different beast surgically. Unlike sigmoid volvulus, endoscopic decompression is much less reliable here because the scope has to navigate the full length of the colon to reach the cecum, and even when it gets there, the anatomy makes it harder to untwist. Surgery is the primary treatment in most cases.¹⁴

The standard operation is a right hemicolectomy, which removes the cecum and part of the ascending colon and connects the small bowel to the remaining colon. When the bowel is gangrenous or severely distended and thin-walled, resection is mandatory. For viable bowel, surgeons sometimes consider less aggressive options like cecopexy, where the cecum is simply tacked down to the abdominal wall so it cannot twist again, or cecostomy, where a tube is placed through the abdominal wall into the cecum to decompress it. However, evidence suggests cecopexy and cecostomy are less effective and carry higher complication rates than resection with anastomosis.¹⁵ For that reason, most surgeons default to right hemicolectomy unless the patient is extremely poor surgical candidate.

There is growing interest in performing this operation laparoscopically. A single-incision laparoscopic approach has been reported successfully for acute cecal volvulus, though this remains technically demanding and is not yet standard practice.¹⁴

Volvulus During Pregnancy

Colonic volvulus during pregnancy is rare but exceptionally dangerous. The growing uterus displaces bowel loops, and the hormonal slowdown of gut motility during pregnancy creates conditions ripe for a twist, especially in women who already have chronic constipation. Sigmoid volvulus is the most common type in pregnant patients, and the consequences of delayed diagnosis can be devastating. In one reported case at 33 weeks of gestation, a sigmoid volvulus led to complete necrosis of the left colon.¹⁶

Diagnosis is tricky because abdominal pain and bloating are common complaints during normal pregnancy, and doctors are reluctant to expose a fetus to radiation from CT scans. This often leads to delays. A particularly grim case report described a pregnant woman with severe constipation whose sigmoid colon twisted around the uterus itself, perforating and resulting in the deaths of both the fetus and the mother within hours of symptom onset.¹⁷ These cases underscore that severe abdominal pain in a pregnant woman with a history of constipation warrants urgent evaluation beyond assuming the usual discomforts of pregnancy.

Children and Intestinal Malrotation

In children, a twisted bowel most often involves the small intestine rather than the colon, and it typically stems from a congenital condition called intestinal malrotation, where the gut did not rotate into its normal position during fetal development. The loose attachments that result make midgut volvulus a risk, particularly in infants. Vomiting, especially bilious (green) vomiting in a newborn, is the classic alarm sign. In older children between 6 and 15 years, abdominal pain becomes the dominant symptom instead.¹⁸

Colonic volvulus in children is unusual. When it does happen it follows the same principles as in adults, but the causes are more likely to be congenital abnormalities or Hirschsprung disease (where nerve cells are missing from part of the colon, leading to massive distension) rather than the acquired redundancy seen in elderly patients.

What Recovery Looks Like

Recovery varies enormously depending on whether you had a simple endoscopic decompression or major abdominal surgery. After decompression, most patients go home within a day or two, but they leave with the knowledge that the problem is likely to return. Dietary changes that keep stools soft and regular, along with addressing any underlying constipation, can help extend the interval between episodes but are unlikely to prevent recurrence entirely.

After surgical resection, recovery follows the usual trajectory for major bowel surgery: a hospital stay of several days to a week or more, a gradual return to normal eating as the reconnected bowel begins to function, and several weeks before full activity resumes. Patients who receive a stoma face the additional adjustment of managing a colostomy bag and the prospect of reversal surgery down the line.

Research into patient experiences after sigmoid volvulus has identified quality of life, anxiety for both patients and their caregivers, and the impact of repeated hospital admissions as major concerns that are often overlooked in clinical discussions focused purely on surgical outcomes.¹⁹ Many patients describe a cycle of dread between episodes, particularly those who have been decompressed multiple times but not offered surgery.

The Geographic Puzzle

One of the more interesting aspects of colonic volvulus is its strikingly uneven distribution around the world. Researchers describe a “volvulus belt” stretching across sub-Saharan Africa, the Middle East, parts of South Asia, and Russia, where sigmoid volvulus is far more common than in Western Europe or North America.³ The prevailing explanation involves diet: populations that consume large volumes of high-fiber food produce bulkier stools, which over years can stretch the sigmoid colon into the long, redundant loop that is vulnerable to twisting. In contrast, in Western settings the condition clusters among the elderly and institutionalized, where immobility and medication-induced constipation are the main drivers.

Altitude may also play a role. Some researchers have noted higher rates of volvulus in populations living at high elevations in Ethiopia, Bolivia, and other mountainous regions, though the mechanism behind this geographic pattern remains debated. What is clear is that volvulus is not a rare curiosity in global terms. In many parts of the world it is one of the leading causes of bowel obstruction, and delays in surgical access make outcomes considerably worse in low-resource settings where the condition is most common.

Distinguishing Volvulus from Pseudo-Obstruction

A condition that can look almost identical to volvulus on initial presentation is acute colonic pseudo-obstruction, sometimes called Ogilvie syndrome. Both cause massive abdominal distension, pain, and an X-ray showing a hugely dilated colon. The critical difference is that pseudo-obstruction involves no mechanical twist: the colon simply stops contracting, usually in the setting of hospitalization, recent surgery, or serious illness. Treatment is different too, often involving medications that stimulate the colon to move rather than surgery.⁷ CT scanning reliably tells the two apart, which is one more reason imaging is so important when a patient shows up with a grossly distended abdomen.