Congenital diaphragmatic hernia associated with homolateral upper limb malformation: a study of possible pathogenesis in four cases.

Four cases of congenital diaphragmatic hernia associated with homolateral upper limb reduction deformities are presented and are analyzed in terms of their pathogenesis. Diaphragm and upper limb are supplied by adjacent segments of cervical neural crest, and the sensitive period for upper limb formation occurs during early neural crest development. The evidence supports the possibility of cervical neural crest injury as the underlying pathogenesis.