Diaphragmatic hernia is a defect or hole in the diaphragm that allows the abdominal contents to move into the chest cavity. Treatment is usually surgical. Diaphragmatic hernia is a defect or hole in the diaphragm that allows the abdominal contents to move into the chest cavity. Treatment is usually surgical. A scaphoid abdomen (sucked inwards) may be the presenting symptom in a newborn.