Osteoporosis Flashcards
What is osteoporosis?
A skeletal condition characterised by:
- low bone mass
- deterioration of bone tissue
- disruption of bone architecture
Leading to compromised bone strength + increased risk of fracture
How is bone mineral density measured?
- Using DEXA scan (dual energy x-ray absorptiometry)
- a type of x ray that measures how much radiation is absorbed by the bones
- the femoral neck reading is most important
Diagnosis of osteoporosis
- DEXA of lumbar spine + hip (gold standard)
- T score: number of standard deviation from the man bone density of person of the same gender at age of peak density (<2.5 = osteoporosis)
What is the T score?
The number of standard deviations from the mean bone density of persons of same gender at age of peak density
What do different T score values mean?
- Normal: more than -1
- osteopenia: -1 to -2.5
- oesteoporosis: < -2.5
- severe osteoporosis: < -2.5 and a fracture
Risk factors of osteoporosis
- increasing age
- female
- menopause
- Caucasian or south Asian
- family history
- history of low trauma fracture
- calcium or vitamin D deficiency
- smoking + excessive alcohol
- long term corticosteroids
- low BMI
- inadequate physical activity
What is type 1 primary osteoporosis?
Who does it affect?
Due to increased in osteoclast number
Loss of oestrogen after menopause
Affects post menopausal women
What is type 2 primary osteoporosis?
Who does it affect?
Loss of oestoblast function
Loss of oestrogen + androgen
Affects older men + women
What is secondary osteoporosis?
Due to :
- drug therapy
- metabolic bone diseases
- malnutrition/weightlessness
Leads to:
- damaged bone remodelling
- causing porous appearance
- results from incomplete filling of oestoclast resorption bays
Causes of secondary osteoporosis
- coeliac disease
- eating disorders
- hyperparathyroidism
- hyperthyroidism
Management of osteopenia
Focussed on risk modification;
- weight bearing exercises
- vitamin D supplements 800-2000 IU/day
- limiting alcohol
- smoking cessation
Management of osteoporosis
- address reversible risk factors
- Vitamin D + calcium supplements
- 1st line: oral bisphosphonates e.g. alendronic acid
- 2nd line: denosumab or teriparatide
What are adverse drug reactions of bisphosphonates?
- reflux + oesophageal erosions
- atypical fractures
- osteonecrosis of jaw + external auditory canal
What advice should be given to patients when taking bisphosphonates?
- taken on empty stomach with full class of water
- sit upright for 30 mins after before moving or eating
Who should be assessed for osteoporosis?
- anyone one long term steroid use
- anyone with previous fragility fracture
- 50+ with risk factors
- all women 65+
- all men 75+
