Neurotomes and birth defects: a neuroanatomic method of interpretation of multiple congenital malformations

It has been suggested that complexes of multiple congenital malformations, involving limbs and viscera, may be caused by embryonic neural crest injury. Structures supplied by the sensory and autonomic nerves derived from the injured zone of crest would suffer defective development through presumed impairment of neurotrophic influence. Our study aimed to examine this concept by a retrospective analysis of autopsy findings in 27 babies who died of multiple congenital malformations associated with longitudinal limb defects. Sclerotome maps of the segmental sensory innervation of the skeleton were used to analyse the limb defects in terms of their nerve supply. From a review of the literature, the approximate segmental contribution of neural crest to the autonomic innervation of internal organs was ascertained, and thus "viscerotome" diagrams were constructed. Application of sclerotomes and viscerotomes to the data derived from the autopsy reports showed a neuroanatomic correlation in 89% of cases. Interpretation of multiple malformation syndromes is proposed on the basis of neurotomes, or embryonic developmental fields with common regional innervation.