Distinctive appearance of the distal phalanges in children with primary hypothyroidism.

An osseous projection from the midportion of the metaphysis of the distal phalanges of the digits was seen in 79% of untreated children with primary hypothyroidism. There is a significant difference (p less than .0005) in the incidence of this projection between children with primary hypothyroidism and those with idiopathic hypopituitarism or psychosocial dwarfism. The presence of this projection together with delayed skeletal should suggest primary hypothyroidism.