Volvulus neonatorum is usually due to a defect of normal rotation of the bowel where the caecum remains high, often with a congenital banding passing across the duodenum, which may thus also be obstructed.
A narrow attachment of mesentery suspends the caecum and midgut, which thus are at risk of developing a volvulus.
The volvulus normally develops just below the ampulla of Vater in the duodenum; vomitus is thus bile stained.
If a volvulus develops and is left untreated the whole of the midgut becomes ischaemic and subsequently gangrenous. Prevention of these complications requires treatment in six hours or less from onset.