Flashcards in Bone Pathology Deck (22):
What is Uncalcified bone called?
What receptors are found on Osteoblasts?
What are osteoclasts derived from?
Hematopoetic Progenitor Cells
What pervents parts of bone from being resorbed?
Lined w/ osteoid
What is the difference between Woven and Lamellar bone?
Woven: Random weave
Lamellar: Organized. Stronger
Where is Woven bone seen?
Fetal skeleton and growth plates, Callus, Fibrous Dysplasia, Surrounding tumor or infection
What are the traits of Achondroplasia?
Dwarfism. Def in signal transduction. FGFR Persistently activated. Dec prolif of chondrocytes @ growth plates. AD. HH Lethal
What are the zones of The Growth Plate?
1) Reserve Z
2) Proliferation Z
What are the Clinical findings of achondroplasia?
Shortened proximal extremities
Sway Backed posture
Enlarged head w/ fontanel
What is the defect in Osteogenesis Imperfecta?
Type 1 collagen synthesis
AD. Brittle Bones
What are the 4 major types of OI?
1) inc risk of fracture but not deforming
2) Lethal: In utero demise
3/4) Survive fracures in infancy/childhood but have progressive Deformity
What are the features of OI type 1?
Blue Sclerae, Dental and hearing problems, Inc risk lof fracture
What are the traits of Osteopetrosis?
Marble bone disease
Dec in Osteoclastic bone resorption => skeletal sclerosis. Inc mineralization
Thick brittle bones
What are the hematologic signs of Osteopetrosis?
Anemia, thrombocytopenia, Inc risk of infection
What are the traits of Osteoporosis?
Reduced bone mass
Cortex and Trabeculae are thinned
How do Osteoblast and clasts interact?
RANK ligand on surface of OClast precursor stim by OBlast => diff to mature OClast
What is the Effect of Dec Estrogen on Osteoclasts?
Inc IL-1, IL-6, TNF => Inc RANK => Inc Osteoclasts => Bone resporption => Dec Osteoprotegrin
What are the 2 types of Vertebral Fractures?
Wedge Fracture => Kyphosis
Burst Fracture => SC disruption
What are the effects of Glucocorticoids on the Bones?
Dec Osteoblastogenesis =>
Osteonecrosis and Fracture
What are the traits of Rickets and osteomalacia?
VD Deficiency => Defective Matrix Mineralization
Softening of Bone => Frac/ deformity
What are the Clinical signs of Osteomalacia?