⭐ LECTURE 4: OSTEOPOROSIS Flashcards
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Mother cells
OSTEOPROGENITOR CELLS
immature bone cells and are found on the outer surface of the bone and in the bone cavities
OSTEOBLASTS
Mature bone cells
OSTEOCYTES
Large, phagocytic, multinucleated derivatives of monocytes or monocyte-like cells formed in the bone marrow
OSTEOCLASTS
What are the 2 types of growth in BONE REMODELING?
Linear Growth
Appositional Growth
initiates remote signal by activating the macrophages
ACTIVATION PHASE
will begin once osteoclasts are activated by RANKL and M CSF to release calcium and phosphorus
RESORPTION PHASE
osteoclasts will disappear and will undergo apoptosis
REVERSAL PHASE
bone calcification will begin once collagen molecules are secreted
FORMATION PHASE
Imbalance that occurs in bone resorption and bone formation due to:
-Decrease in bone resorption
-Increase in bone resorption
-Combination of both
OSTEOPOROSIS
What are the signs and symptoms of OSTEOPOROSIS
For menopausal women: lose 25-30% of spongy bone and 10-15% of cortical bone
What are the PRIMARY HORMONES?
PTH, Vitamin D, Fibroblast Growth Factor 23 (FGF23)
What are the SECONDARY HORMONES?
Calcitonin, Glucocorticoids, Estrogen, Prolactin, GH, Insulin, Thyroid Hormone
Albumin is at low level = decrease level in calcium
HYPOALBUMINEMIA
exhibition of Low level of ionization
and in favor of ionization
Acidosis
Disfavors ionization
Disfavors ionization
This primary hormone Promotes bone formation and resorption by stimulating osteoblasts and osteoclasts
PTH
This primary hormone Stimulates intestinal absorption of Ca and phosphate and Promotes bone formation and resorption by stimulating the osteoblasts and osteoclasts
Vitamin D
This primary hormone Stimulates P excretion in the kidney = hypophosphatemia and low levels of 1,25(OH)2D3
Fibroblast growth factor
This secondary hormone Lowers Ca and P and Inhibits osteoclastic bone resorption
Calcitonin
excess PTH promotes?
an increase in bone resorption
low PTH promotes?
an increase in bone formation
What are the common sites for osteoporosis related fracture?
Vertebrae
Hip
Distal radius