[Scanning and transmission electron microscopic studies of the development of the joint surfaces (author's transl)].

The late embryonic and post partum development of the rat knee-joint has been studied by the transmission and scanning electron microscope. Undergoing a transformation in the sense of functional adaption to extrauterine life there is a final breakdown of the mesenchym cell layer (interzone) which separates in the embryo the anlagen of the bones. Its is followed by an accelerated growth of the collagen-containing intercellular substance which finally forms the surface.