Fetal midgut rotates in IUL
During development, midgut undergoes rapid phase of growth in which loops of midgut herniate outside the abdominal cavity of fetus & protrude into umbilical cord This is PHYSIOLOGICAL UMBILICAL HERNIA (occurs at 6 weeks of IUL) At week 10, it comes back to abdominal cavity. When midgut is Herniating into umbilicus, it follows superior mesenteric aery Thus, superior mesenteric aery becomes axis of rotation. While entering umbilical cord there is: 1. High point: duodenojejunal junction (small intestine). 2. Low point: ileocecal junction (large intestine) * Which rotates 1st 90 degree anti- clock wise resulting in small intestine to right side & large intestine to left side. While coming back to abdominal cavity, there would be another 180 degree anti - clock wise rotation. : Total of 270 degree anti-clock wise rotation occurs during development of midgut in IUL Duodenum become C - shaped and have 4 pas and colon will also have 4 pas (Ascending, transverse & descending & sigmoid colon).
270 degree clockwise
270 degree anticlockwise
360 degree clock wise
360 degree anticlockwise
Mesentry, neurovascular bundle