[Disorders of finger flexion crease formation in various congenital anomalies of human development].

Deviations in finger flexion crease formation and ridge counts were analysed in normal and deformed (Down syndrome, arthrogriposis, diastrophic dysplasia) hands. Certain interrelation was found between decrease in the ridge count and the number of the finger flexion creases in Down syndrome. The changes observed agree with the hypothesis that intersegmental borders, and later, the joints and finger flexion creases are laid out on the basis of the positional information which is directed by morphogenetic gradients. This model enables us to interpret more or less unequivocally the changes in flexion creases in patients with arthrogriposis and diastrophic dysplasia (dwarfism).