Osteoporosis Flashcards
Osteo?
bone
Porosis?
Cavity formation (bone is becoming porous, developing holes)
Osteoporosis?
Loss of bone mass (atrophy of bone)
Briefly summarize what osteoporosis is.
Loss of bone mass -> increase fragility of bones -> fractures
ethology of osteoporosis?
- genetic predisposition (PEAK BONE MASS)
- ageing
- ## loss of estrogen at menopause (estrogen supports bones)
how does peak bone mass relate to genetic predisposition?
PBM can be high or low based on genetics (some people may begin with a low bone mass so any loss will result in more rapid development of osteoporosis)
What are the 2 major risk factors of osteoporosis?
- low peak bone mass
2. post menopausal women (loss of estrogen)
Around what age does bone loss begin?
30 years old
Why are post menopausal women at risk for osteoporosis?
Estrogen production is decreased, estrogen has a protective effect on the bone. It is involved in maintaining the balance between osteoblast and osteoclast activity -> produces mediators to inhibit osteoclast activity and regulate breakdown. Loss of estrogen = decreased osteoclast inhibition
Patho of osteoporosis?
Bone remodelling occurs in the skeleton constantly by replacing old matrix with new matrix. Peak bone mass occurs at around 30 years of age. After this time you are only losing bone and you stop building up bone matrix (however, the amount lost depends on your lifestyle). peak bone mass is lost at ~0.7% per year. Imbalance between formation and resorption of bone -> losing bone on an ongoing basis. Micro damage -> bone is internally damaged.
What percentage of peak bone mass is lost annually after around 30 yrs of age?
~0.7%
If you have 100% peak bone mass at 40 years old, what will you have at 41?
99.3%
How much peak bone mass is lost for post-menopausal women?
> 2% / year
In osteoporosis, in what part of the bone do most changes occur in?
In the diaphysis and metaphysic which is where most bone growth occurs
Manifestations of osteoporosis?
- Usually silent until fracture
- acute, severe pain
loss of bone: - spinal distortion
- mandible and dentition
- vertebrae -> change in stature
Explain what occurs when there is a loss of bone and spinal distortion occurs.
breathing problem occurs because with osteoporosis, you will see the pt with a hunch because they cannot sit upright. With a hunch, you are applying pressure on the lung and the lungs are not able to expand fully.
Why is the mandible and dentition affected in osteoporosis?
Cant chew hard foods -> impacts diet and dietary deficiencies occur
diagnostics for osteoporosis?
- bone density scans
- dual- energy X-ray absroptiometry
- Xray
What is the principle of bone density scans?
it passes photons of light through the bone (if the bone is less dense, more light will pass through).
Which structures are the photons passed through in bone density scans?
- lumbar spine
- radius
- neck of femur
Bone is rated on a T-score between 1-2.5. list what the following T scores indicate:
- 0
- -1
- (-1) - (-2)
- bone is normal
- low risk of osteoporosis
- osteopenia -> essentially a precursor to osteoporosis, you will develop it
Osteopenia?
decrease in mineral density of bone
Goal of Osteoporosis?
- prevention of boneless and early detection
Treatment of Osteoporosis?
- adequate calcium and vitamin D consumption
- weight-bearing activity (stimulates osteoblast activity)
- pharmacology: anti-resorptive agents and anabolic agents
Purpose of anti-resorptive agents?
inhibits osteoclast activity
Purpose of anabolic agents?
enhance osteoblast activity
Complication of osteoporosis?
fractures
