Longitudinal limb deficiencies and the sclerotomes - An analysis of 378 dysmelic malformations induced by thalidomide

The pathogenesis of longitudinal reduction deformities of the limbs, or dys melia, is still a matter of debate, Their morphological pattern was defined from a large collection of radiographs of children with dysmelia following the thalidomide disaster. We compared radiographs of 378 of these limbs with the sclerotomes which ar e areas of segmental sensory innervation of the limb skeleton defined by th e radiation of referred pain, The pattern of dysmelia matched the sclerotom es closely in 279 limbs (73.5%), The principles of skeletal reduction in dysmelia are explained by the arran gement of the sclerotomes. The congruence between two separate and independ ent data sets shows that both patterns are expressions of the underlying se gmental sensory innervation of the skeleton, and that the sensory nervous s ystem is involved in the process of limb morphogenesis and teratogenesis.