Fingers, toes, palmar and plantar arches

In vertebrates from Amphibia to Man there are striking similarities between thoracic and pelvic limbs, between hands and feet, between fingers and toes. Most standard textbooks of Human Anatomy describe the foot by pointing to similar features in the hand: the extensor apparatus of the toes, for instance, is usually dispatched in a few words as being the same as in the fingers, the axis of attachment of the interossei presenting the only difference. One concept, however, has evolved in reverse, starting in the foot, namely the arch.