Minimally conjoined omphalopagi: emphasis on embryogenesis and possibility of emergency separation

Minimally conjoined omphalopagus twins (MCOTs) has been recognized in the last decade as a special subgroup in which omphalopagus twins have union of peritoneal cavities through anterior lower abdominal wall defect with union of distal small intestine and patent urachal structures and associating anorectal malformation. A careful review of the current literature revealed that MCOTs have usually been separated in emergency situations within the first hours of life due to ruptured omphalocele, gastroschisis, stillbirth of one of the twins, intestinal obstruction, or requirement of enterostomy for cloacal anomaly. Pediatric surgeons should be familiar with MCOTs and ready for emergency separation with thorough knowledge of the anatomical relationships of the connecting structures and the embryologic basis for this anomaly. We present a new set of MCOTs separated in emergency conditions with a review of the relevant English literature. We give special emphasis to the common surgical characteristics and a brief discussion on the embryogenesis of this rare condition.