Bone physiology Flashcards
True or False
One vertebral fracture will lead to another
True
What do osteoclasts do?
Resorb bone
What do osteoblasts do?
Put down osteoid to form new bone
Who should be assessed using the risk factor assessment? (2)
Anyone over 50 with risk factors
Anyone under 50 with an early menopause or on steroids
When should a DEXA scan be requested?
10 year risk assessment of at least 10%
In a DEXA scan, which value is the most important?
T value
What does the T value have to be to be classified as osteoporosis?
More than -2.5
What is a Z score?
Age matched so compares with age and size
When are Z scores used?
If younger than 20
What class of drug is given if osteoporosis is diagnosed?
Bisphosphonate
What are examples of bisphosphonates?
Alendronic or risedronic acid
When is zolendronic acid given?
If DEXA intolerable
What is given in severe spinal osteoporosis?
Teriparatide
If osteopenia is diagnosed what is done?
Lifestyle advice e.g. smoking, alcohol, weight bearing exercise, falls advice
DEXA reassessment
True or False
Post-menopausal women should increase their dairy intake
True
How do bisphosphonates work?
Apoptosis of osteoclasts so inhibit bone resorption
What are long term potential side effects of bisphosphonates?
Osteonecrosis of jaw
Oesophageal Ca
How is zolendronic acid given?
Once yearly IV infusion
When is denosumab given?
If bisphosphonates intolerable.
How should alendeonic acid be given?
Tablet, 30 minutes before food and don’t lie down for half an hour after
When should alendronic acid be stopped?
Oesophagitis or ulcers
What are common side effects of alendronic acid?
Abdo pain
Nausea
dyspepsia
GI side effects
How does denosomuab work?
Monoclonal Ab that binds to RANKL
What is RANKL?
Receptor activator of nuclear factor kB ligand
How does activating RANKL prevent osteoporosis?
Inhibits osteoclasts and decreases bone resorption
How is denosomuab given?
Subcut injection 6 monthly
Why is strontium not recommended as 1st line?
Fracture reduction is slightly less and dangerous in heart disease