Table 1: Midgut rotation abnormalities.

Type

Defect

Clinical effect

IA

No rotation

Midgut volvulus

IIA

Lack of duodenal rotation, regular colon rotation

Duodenal band obstruction

IIB

Reverse rotation of duodenum and colon

Transverse colon obstruction by the duodenal mesentery

IIC

Reverse rotation of the duodenum; normal rotated colon

Right mesenteric pouch (obstruction)

IIIA

Regular rotation of the duodenum; the colon does not rotate.

Midgut volvulus

IIIB

Incomplete fixation of the hepatic angle of the colon

Ladd’s band obstruction

IIIC

Incomplete fixation of the cecum and its mesentery

Cecal volvulus invagination (Waugh’s syndrome)

IIID

Internal hernias

Paraduodenal hernia

Taken from: Ballesteros GE et al.3