On obstetric fractures. Kefer (Orth. and Traum., 1928, vol. 5-6)

The femur, shoulder and clavicle were fractured during childbirth, mostly in the diaphyseal part. Usually the periosteum in these fractures is intact due to its strength and considerable thickness and fits around the bone fragments like a socket. Newborn bones, poor in salts, are less fragile than in adults and do not form sharp ends; because of this, fractures occur as "fractures en bois vert" ("green twig fracture"), without length and lateral displacement, but simply bent at an angle. In addition, muscle retraction in newborns is weakly expressed.