Metaphyseal dysplasia, epiphyseal dysplasia, diaphyseal dysplasia, and related conditions. I. Familial metaphyseal dysplasia and craniometaphyseal dysplasia; their relation to leontiasis ossea and osteopetrosis; disorders of bone remodeling.

THE DEVELOPMENT of a bone is a complicated process. A long bone arises from a solid mass of mesenchyme which turns into a strong but delicate and light tubular structure, constantly adapting its architecture to the needs of bodily growth and stresses and strains. METAPHYSEAL DYNAMICS The metaphysis of a bone is that part of its shaft which adjoins the epiphysis; we do not attempt to define its exact extension in the other direction. It is that part of the bone where the effect of recent events is often shown—the transverse lines produced by any serious illness, the dense bands of elemental phosphorus poisoning, the chondromas arising from nests of trapped epiphyseal cartilage cells, and so forth. It is particularly here that deficient molding and remodeling of a growing bone may be seen. Thus, the normal graceful and rapid tapering from the wider epiphysis to the narrower tubular shaft