title: Normal and heterotopic periosteum.
abstract: Normal periosteum is an osteoprogenitor cell-containing bone envelope, which can be activated to proliferate by trauma, retroviruses, tumors, and lymphocyte mitogens. Activated periosteum produces cartilage and bone, and is colonized by bone-resorbing cells. The osteogenic activity of periosteum is maintained in heterotopic sites and in vitro. Ectopic bone, however, is colonized by bone marrow precursor cells but does not develop a true periosteum. The absence of true periosteal envelope in the heterotopically induced bone may be the major, if not the only, difference between heterotopic and orthotopic bone deposits.
authors.affiliation: Department of Histology and Embryology, Institute of Biostructure, Medical Academy, Warsaw, Poland.
authors.forename: K H
authors.initials: KH
authors.lastname: Włodarski
mesh_terms: D000818:Animals; D006801:Humans; D066298:In Vitro Techniques; D010012:Osteogenesis; D010521:Periosteum / Q000033:anatomy & histology / Q000502:physiology*; D013234:Stem Cells / Q000502:physiology