My attention was recently drawn by Dr. Henry L. Jaffe, director of the laboratories at the Hospital for Joint Diseases, to a number of cases (4 from this and 4 more from other hospitals from which pathologic material was studied) presenting multiple osseous lesions and having sufficient features in common to differentiate them as a distinct clinical entity. The condition is designated as polyostotic fibrous dysplasia, for reasons to be indicated presently.
DEFINITION AND NOMENCLATURE
The name "polyostotic fibrous dysplasia" is being used in the Hospital for Joint Diseases to designate a skeletal developmental anomaly affecting several or many bones with predominantly unilateral involvement. The involved bones show filling of their medullary cavities by gritty, grayish white fibrous tissue containing trabeculae of newly formed primitive bone. The condition apparently results from perverted activity of the specific bone-forming mesenchyme. It manifests itself in childhood or early adult life and evolves slowly,