exstrophy

exstrophy /ek″strōfē/ [Gk, ekstrephein, to turn inside out] , a congenital malformation in which a hollow organ has its wall turned inside out, establishing a communication with the exterior. An example is exstrophy of the bladder with eversion of the posterior bladder wall, which causes urine to drain to the exterior.

Boy with extrophy (Nelson, 2013)