Volvulus is defined as the twisting of a loop of bowel on its mesentery and is one of the most common causes of intestinal obstruction. Volvulus in a neonate or infant almost always presents as a midgut volvulus secondary to intestinal malrotation. Patients typically show features of bowel obstruction (abdominal pain, distension, bilious vomiting) or of bowel ischemia and gangrene (tachycardia, hypotension, hematochezia, peritonitis) in severe cases. Upper GI series is the investigation of choice in infants with suspected midgut volvulus, which is seen as a cork-screw duodenum. The Ladd procedure (laparotomy and detorsion of the volvulus) is indicated in all patients with intestinal malrotation since it is impossible to predict if volvulus of the midgut will occur in an asymptomatic patient or not.
- Incidence: symptomatic malrotation (midgut volvulus) in 1:6000 live births in the United States
- Age: neonates and infants 
Epidemiological data refers to the US, unless otherwise specified.
- Intestinal malrotation: arrest in the normal rotation of the gut in utero, resulting in an abnormal orientation of the bowel and mesentery within the abdominal cavity
- Normal intestinal rotation: the midgut starts to elongate in utero (4th week) → herniation of the midgut out of the umbilicus (6th week) → 90° counter-clockwise rotation of the midgut → re-entry of the midgut into the abdominal cavity(10th week) → 180° rotation inside the abdominal cavity (a total of 270°) → fixation of the duodenojejunal flexure and cecum to the posterior abdominal wall
|Common types of intestinal malrotation |
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Midgut volvulus: torsion of a malrotated midgut causing mechanical bowel obstruction, mostly in neonates and infants
Torsion of bowel on its axis 
- Closed-loop mechanical bowel obstruction → accumulation of gas and feces within the loop → increased intraluminal pressure → impaired capillary perfusion of bowel → bowel strangulation, ischemia, and gangrene
- Torsion of the mesenteric vascular pedicle → occlusion/thrombosis of mesenteric vessels → bowel strangulation, ischemia, and gangrene
- Torsion of bowel on its axis 
- Malrotation: mostly asymptomatic
- Midgut volvulus
- Features of duodenal obstruction: bilious vomiting without abdominal distension
- Variable presentation in older children/adults: recurrent episodes of abdominal pain and vomiting; failure to gain weight; malabsorption 
- Abdominal examination is unreliable in neonates/infants because abdominal tenderness/rebound tenderness is difficult to assess in this population.
- Features of associated congenital anomalies
- Commonly associated anomalies: ∼ 100%) ; (up to 90%); (up to 45%) (
- Less commonly associated anomalies: ; ; ;
- Work-up follows the same protocol as that for bowel obstruction. Only the specific findings seen in intestinal malrotation and midgut volvulus are mentioned here.
- See “Sigmoid volvulus and cecal volvulus” for more details of volvulus occurring in adults.
- Laboratory studies: complete blood count; electrolyte levels; arterial blood gas analysis 
|Imaging in intestinal malrotation and midgut volvulus|
Upper GI series (gold standard in hemodynamically stable patients) 
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|Barium enema (lower GI series)|| |
|Abdominal ultrasound || || |
CECT scan (oral and IV contrast)
- In neonates/infants with recurrent vomiting: ; ,
- In neonates with features of bowel ischemia/gangrene: NEC) (
- In older children with abdominal pain and vomiting:
- In older children/adults with nonspecific symptoms: GERD; chronic mesenteric ischemia; food allergy
- See “ .”
The differential diagnoses listed here are not exhaustive.
Midgut volvulus with/without peritonitis
- Initial resuscitation: NPO; nasogastric tube insertion; IV fluids; correction of electrolyte imbalance; broad-spectrum IV antibiotics
Emergency surgery (Ladd procedure) 
- The volvulus is reduced/untwisted and the Ladd bands removed.
- Gangrenous/necrotic bowel, if present, is resected and either anastomosed or created into a stoma.
- Appendix is removed (to prevent future diagnostic/operative difficulties)
- Development of postoperative adhesions decreases the chance of recurrent volvulus.
- Incidentally detected/asymptomatic intestinal malrotation: elective surgery (Ladd procedure)