Ectopic lungs in a human fetus with Klippel-Feil syndrome

The hyperplastic lungs protruding out of the thoracic cavity are described in a full term still-born male cotwin having Klippel-Feil syndrome, single umbilical artery, dextrocardia and a right sided aorta. Both lungs herniated into the abdomen through bilateral defects in the diaphragm. The righ lung, in addition, herniated superiorly toward the base of the skull. The pulmonary herniation appears to be due to spinal retroflexion which reduces the capacity of the thoracic cage. The various anomalies observed can be attributed to the disturbances caused by single umbilical artery.