Bone Disorders

Question 1

What is Osteoporosis?

Answer 1

Progressive systemic skeletal disease characterised by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture

Question 2

What symptoms occur with osteoporosis?

Answer 2

None

Question 3

Where are common fracture sites?

Answer 3

Neck of femur
Vertebral body
Distal radius
Humeral neck

Question 4

What does continual remodelling cycle called bone remodelling units contribute to?

Answer 4

Calcium homeostasis and skeletal repair

Question 5

What score systems are there for osteoporosis risk factors?

Answer 5

FRAX and Qfracture

Question 6

Who should be assessed with score systems?

Answer 6

Anyone >50 with risk factors

Anyone

Question 7

When should you refer to DXA?

Answer 7

Anyone with a 10 year risk assessment for any OP fracture of at least 10%

Question 8

What can predict risk, without other risk factors being accounted for?

Answer 8

Bone mineral density

Question 9

What is used for measuring bone mineral density?

Answer 9

DEXA scans

Question 10

What is normal BMD?

Answer 10

within 1 of SD of young adult mean

Question 11

What defines osteopenia?

Answer 11

BMD within >1 SD below young adult mean

Question 12

What defines osteoporosis?

Answer 12

BMD >_2.5 SD below young adult mean

Question 13

What defines severe osteoporosis?

Answer 13

BMD >_2.5 SD below young adult mean with fragility fracture

Question 14

What score is reported if the patient is under 20?

Answer 14

Z score only

Question 15

What bloods would be taken for osteoporosis?

Answer 15

U+E’s, LFT’s, Bone biochemistry, FBC, PV, TSH

Question 16

What other things should be checked for in osteoporosis?

Answer 16

Protein electrophoresis 
Bence Jones proteins
Coeliac antibodies
Testosterone 
250H vitamin D
PTH

Question 17

What can cause secondary osteoporosis?

Answer 17

Hyper(para)thyroidism
Cushing's disease
Coeliac, IBD, chronic liver, chronic pancreatitis
CF, COPD
CKD

Question 18

What dieting can help with osteoporosis?

Answer 18

RNI 700mg calcium (2-3 milk portions)

Postmenopasusal - 1,000mg of calcium

Question 19

Describe vit D and calcium supplementation

Answer 19

Calcium not to be taken within 2 hours of bisphosphonates

Used to reduce risk of non vertebral fractures

Question 20

Explain bisphosphates

Answer 20

Antiresoptive agents - Alendronate and risedronate
Prevent bone loss at all sites
Reduce spine/hip fracture risk

Question 21

How do bisphosphates work?

Answer 21

Analogues of pyrophosphate that absorb onto bone within matrix
Ingested by osteoclasts leading to cell death thereby inhibiting bone resorption
Filling of resorption sites by new bone increases BMD by 5-8%

Question 22

Describe Zoledronic acid

Answer 22

Once yearly IV infusion for 3 years

5mg in 100mls of NaCl over 15 mins

Question 23

describe Denosumab

Answer 23

Fully human monoclonal antibody that targets and binds with high affinity and specificity to RANKL (factor-kB ligand)
Prevents activation of RANK

Question 24

Describe Strontium Renalate

Answer 24

Antiresorptive agent
3rd line agent
Contraindicated with thromboembolic disease, IHD, Peripheral artery disease, uncontrolled hypertension

Question 25

Describe Teriparatide?

Answer 25

Recombinant parathyroid hormone (1-34)

Stimulates bone growth rather than reducing bone loss - anabolic agent

Question 26

How do corticosteroids directly act on bone?

Answer 26

Reduction of osteoblast activity and lifespan
Suppression of replication of osteoblast precursors
Reduction in calcium absorption

Question 27

How do corticosteroids indirectly act on bone?

Answer 27

Inhibition of gonadal and adrenal steroid production