Focal ring constrictions of the third, fourth, and fifth fingers are seen here on the hand of a full-term newborn infant; secondary edema and discoloration are also seen. The cause of such bands is debated. One hypothesis implicated localized germ cell failure, possibly due to hypoxia. A subsequent theory suggested the deformity was caused by early rupture of the amnion, with resulting bands that could restrict and impair growth of an extremity.


