Metabolic Bone Diseases - Osteoporosis

Question 1

Define OP?

Answer 1

Low bone mass & Micro-architectural deterioration leading to enhanced fragility & fracture risk

Question 2

How do we determine someone’s fracture risk (& so OP risk)?

Answer 2

FRAX
the WHO’s Fracture Risk Assessment Tool

It’s an online risk calculator

Question 3

What is primary OP?

Answer 3

Loss of bone mass due to aging, mostly in post-menopausal women

Question 4

What is secondary OP?

Answer 4

Loss of bone mass due to a drug or other disease

Question 5

How does OP help us understand little old ladies?

Answer 5

If trabecular bone is affected they get crush fractures in their vertebrae. One of the reasons little old ladies are so little.

If cortical bone is affected they get long bone fractures, hence all the broken hips

Question 6

A huge number of things can cause secondary OP. List some of the major ones?

Answer 6

RA
Cushing's disease
IBD
Malabsorption by any cause e.g. CF, coeliac or CP
Liver damage e.g. PBC 
Steroids
Hyper/hypoparathyroidism
Low Testosterone

Question 7

SHATTERED is a useful mnemonic for OP risk factors:

Answer 7

S - Steroids
H - Hyperthyroid/parathyoid/calciuric
A - Alcohol & Tobacco
T - Testosterone low e.g. anti-androgens
T - Thin (<22BMI)
E - Early Menopause
R - Renal or liver failure
E - Erosive bone disease e.g. RA
D - Dietary Ca low or malabsorption

Question 8

How do we test for OP?

Answer 8

FRAX and/or Q fracture risk calculators

DEXA bone scan

Bloods (ALKP/ Ca / PO4 all normal)

Question 9

What is a DEXA bone scan?

Answer 9

Basically a special X-ray that determines bone density

Used on any patient >50 who gets a low-trauma fracture

Question 10

How do we treat OP?

Answer 10

Start by minimising the risk factors
Fall prevention strategies
Ca/VitD supplements
Meds

Question 11

What meds are used in OP?

Answer 11

Bisphosphonates
Raloxifene (SERM)
Denosumab (Monoclonal Ab)
Teriparatide
HRT

Question 12

How do we give bisphosphonates for OP?

Answer 12

Orally
Requires good renal function & Vitd/Ca status
Notify dentist

Question 13

What is Raloxifene?

Answer 13

A selective Oestrogen Receptor Modulator (SERM)

Reduces vertebral fracture rates but risks hot flushes and blood clots

Question 14

How does Denosumab work?

Answer 14

Given by SC injection every 6 months it decreases osteoclast activity
Best in patients with renal impairment who can’t take bisphosphonates

Question 15

What is Teriparatide?

Answer 15

Recombinent Parathyroid Hormone

Question 16

When is HRT used for OP?

Answer 16

It’s used in recently menopausal women to prevent OP. Should be tapered off in late fifties otherwise its associated with a high risk of clots, breast cancer and Heart disease