Bones Are Alive And Adaptable Flashcards
What 3 things do bones do?
Growth
Repair (macro damage; micro damage)
Remodel
Wolff’s law
Bone grows or remodels in response to the demands placed on it
What are the 3 “loading: activity level”?
Unloading
Compressional loading
Tensile loading
What are 2 other things taken into consideration for bone remodeling?
Age
Hormones
The bone remodeling process depends on _________ of bone, not ____________.
Quantity; composition
Resorption
Removing bone
What are the 3 steps so bone is remodeled through resorption?
Bone is unloaded
Needs to be repaired
Osetoclasts
Deposition
Adding bone
What are the 2 steps in bone remodeling through deposition?
Bone is loaded
Osteoblasts
Unloading
Decrease bone mass
Compressional loading
Increase mass; increase cross-sectional area
Tensile loading
Increase mass at bony attachment site (ex. For femur: tubercles, tuberosities, and lines)
Combined compression and tension
Bending moments created compression and tension
Age: early life, fetal-25 years
Resorption < deposition
Age: Mid-life, 25-50 years
Resorption = deposition
Age: late life, 50+ years
Resorption > deposition
What is does the parathormone/parathyroid hormone do?
Detects and reacts to drop in blood calcium level; On parathyroid gland
Steps of the parathormone:
1. ________ level in blood drops
2. ___________ parathormone released from __________ gland
3. __________ begin resorption of bone
4. ______ constituents released into blood
5. Blood __________ level rises
Calcium
Increased; parathyroid
Osteoclasts
Bony
Calcium
What are the 2 main functions of estrogen and androgen?
Inhibit osteoclasts
Promote new bone deposition
This is when estrogen secretions decrease in women.
Menopause
Osteoporosis: bone mass _______ as bone resorption _________ bone deposition.
Declines; outpaces
Calcium, Vitamin D, weight-bearing exercises, and hormone replacement therapy are all treatments to what?
Osteoporosis
