Robert Scranton 2008 ©

 Give definition of intramembranous bone formation  Occurs in condensed CT w/o cartilage precursor  Happens in:  Mesenchyme & Peri-/end-ostium  Think flat bones, skull, clavicvle, scapula  Give the steps:  Condensation  Vascularization  Differentiation  Secretion  Calcification  Repeat

 Give definition of endochondral bone formation  Mesenchyme condensation to make cartilaginous model, cart. degenerates and replaced by bone  Happens in:  Long bone development  Give the steps:  Condensation  Differentiation  Bone Collar/ Degeneration  Vascularization  osteogenesis  1° ossification center/ cartilage proliferation  2° ossification centers

 When a bone gets wider, that is ______ growth occuring in the _______ region. It happens by ________ bone formation.

Acute Destroy old Bone Hemorrhage/ Clot Macrophage cleanup of clot, matrix & cells Soft Callus Cellular proliferation for filling w/ CT Hyaline cartilage islands Bony Callus Cartilage replaced by Bone Intramembranous at outer and inner edges Remodeling

Acromegaly (adult prod.) Gigantism (childhood) osteoporosis Too Much Too Little Pituitary Dwarfism

 Achondroplastic dwarfism  Genetic, cartilage doesn’t proliferate, mutation of FGFR3  Endochondrial formation problem, not intramembranous.