FIGURE 21-4. Roentgenographic development of the distal femur. (A) Serial sections from a 3-year-old child (accident victim). Note the differences in the physeal/metaphyseal contours. There is a torus fracture in the distal metaphysis (arrows). (B) Irregular medial ossification (arrow) is evident in this specimen from a 7-year-old. (C) Femur from a 15-year-old showing early stages of physiologic epiphysiodesis.