Split notochord syndrome with dorsal enteric fistula and sacral agenesis.

Split notochord syndrome of the lumbosacral spine in association with dorsal enteric fistula is a rare phenomenon. To date, only nine human cases have been reported in the English literature. We present another case of this type, with sacral agenesis as an additional and unique finding. Several etiological theories are discussed including the persistence of the neurenteric canal, the occurrence of an ectopic or accessory neurenteric canal, a division or local redundancy of the notochord, an entodermal-ectodermal adhesion, neural tube rupture caused by oversecretion of fluid, and failure or aberrancy of dorsal aortic distribution to the region of the neural folds resulting in prevention of timely neural tube closure.