Metabolic bone conditions Flashcards
discuss the pathoogenesis and management for the folowing: -osteoporosis -osteosclerosis -osteomalacia -Paget's
Which 5 factors measured in a blood test differentiate between metabolic bone conditions?
- Ca
- PO4
- Alkaline phosphtase
- PTH
- active form vit D3 =1,25(OH)2 vit D
what is osteoporosis?
loss of bone mass - bone reabsorption > formation
what age does bone mass loss occur?
> 40 yrs loss 0.7% bone mass per year
In females what event speeds up bone loss and why?
MENOPAUSE (increases bone loss 2-9% per year) - loss of oestrogen - omj increase bone reabsorption + decreases Ca absorption from gut
Why is osteoporosis less common in men?
Men have
- more MUSCLE- more stress on skeleton - increases bone mass
- more TESTOSTERONE - anabolic steroid - increases muscle + bone mass
THEREFORE MEN HAVE MORE BONE TO BEGIN WITH THAN WOMEN
What age does bone mineral density peak?
25-27yrs
What is the peak bone mass in both males and females?
males = 1500g
females =1000g
What does bone mass measure?
the total mass of claicum in the skeleton in grams
How is bone mineral density measured?
T or Z score
What is a T score?
no. of SD from young (30yr) + same sex + ethnicity
What is a Z score?
no of SD from old+ same sex + ethnicity
Which is more commonly used + why?
T score - more data been measured for this
What equipment is used to measure T/Z score?
DEX scan
Interpretation of T score for normal/osteopenia/osteoporosis
- normal = +/- 1 SD
- osteopenia = -1 2.5 SD
What type of bone is most suspectible to osteoporosis and why?
trabecular bone -
- greater S.A of sketelon
- finer collagen framework
- in areas suspectible to stress