Neonatal obstructed Treitz's hernia with abdominal cocoon simulating volvulus neonatorum

A case of congenital obstructed Treitz's hernia presenting with bilious vomiting in a newborn baby girl has been presented. Internal herniation of contents within a peritoneal sac of the right paramesocolic hernia formed abdominal cocoon which simulated volvulus neonatorum. Plain radiographs and contrast studies were helpful in defining the nature and extent of the lesion. The patient underwent exploratory laparotomy, reduction of small bowel contents from the hernial sac forming an abdominal cocoon, Ladd's procedure to correct associated midgut malrotation with incidental appendicectomy uneventfully and recovered well.