Lecture 2 Flashcards
(15 cards)
What are cortical bones
Compact bones
- forms 80% of the human skeletal
- slow turnover rate
What are cancellous bone?
Trabecular/spongy bone
- 20% of skeletal mass
- High turnover rate
- less dense
What is WOLFF’S Law
Mechanical stress/gravity stimulate bone remodeling
What is the function of red bone marrow (active)
Blood cell formation
Where is yellow bone marrow (inactive)
Medullary cavity of LONG BONES
What are the cellular components of bone
Osteoblast
Osteocytes
Osteoclasts
Osteoprogenitor cells
What is the function osteoBLAST
Secrete bone matrix that form new bone
(BBB = BLAST BUILD BONE)
What is the function of osteoCYTES
Formed by osteoblast
Mineralization of HOMEOSTASIS + BONE REMODELING
(Cytes = CELL)
What is the function of osteoCLAST
(CLAST = BREAKDOWN)
Responsible for bone resorption
Creates resorptive pits and becomes filled with new bone
- secretes acid + lytic enzymes = breakdown and dissolve
What is primary bone healing?
Bone stabilization is very rigid
- NO CALLUS FORMATION
What is secondary bone healing?
Bone stabilization is less rigid
- CALLUS FORMATION
What are the 3 phases of secondary bone healing
- Inflammatory phase
- Reparative phase
- Remodeling phase
What happens in the inflammatory phase in secondary bone healing
Increased blood flow to the acute injury
- fracture line becomes more visible
What happens in the reparative phase in secondary healing
Forms soft fibrous callus
- fracture line begins to disappear
What happens in the remodeling phase of secondary bone healing
Immature bone is replaced by mature bone
- fracture line has disappear
