Bone physiology

Question 1

Paget’s disease: what

Answer 1

• Disorder of bone remodelling
• Uncontrolled turnover leading to bone remodelling, enlargement, deformity, weakness
• Common in Europe and with older age

Question 2

Paget’s disease: symptoms

Answer 2

• Asymptomatic 70%
• Bone pain and deformity - pelvis, lower limb bones, lumbar spine, skull
• Pathological fractures
• OA
• Deafness/nerve compression
• Cardiac failure

Question 3

Paget’s disease: biochemistry

Answer 3

• High ALP

- Normal Ca+ and PO4

Question 4

Paget’s: management

Answer 4

• Analgesia

- Alendronate

Question 5

Osteomalacia: what (bone and mineral content)

Answer 5

• Normal amount of bone BUT
• Low mineral content

… Called Rickets if happens during bone growth (younger years)

Question 6

What are the metabolic bone diseases?

Answer 6

OP
Osteomalacia/Rickets
Paget’s

Question 7

Osteoporosis: what (bone and mineral content)

Answer 7

• Bone loss BUT

- Normal amount of minerals

Question 8

Osteomalacia: symptoms

Answer 8

• Bone pain
• Fractures
• Symptoms of low PO4 or Vit D

Question 9

Osteomalacia: causes

Answer 9

• Low Vit D (malabsorbed, poor intake, no sunlight)
• Renal failure or liver disease (affect Vit D levels)
• Drugs (affect Vit D levels)

Question 10

Osteomalacia: biochemistry

Answer 10

• Low Ca2+, PO4, Vit D

- High ALP and PTH

Question 11

Osteomalacia: management

Answer 11

• Vitamin D (different variations depending on the cause)

Question 12

Osteoporosis: what

Answer 12

• Reduced bone mass
• 1o (age) or 2o (drugs, etc)
• Affects trabecular bone: vertebral crush fractures
  … and cortical bone: NOF

Question 13

Osteoporosis: risk factors

Answer 13

• Parental history
• Alcohol, smoking
• RA
• Low BMI
• Early menopause
• Steroids
• Renal or liver failure

Question 14

Osteoporosis: investigations

Answer 14

Bone densitometry, FRAX

Ca, PO4, ALP normal

Question 15

Osteoporosis: management

Answer 15

Bisphosphonates
Calcium and Vit D if deficient
Denosumab (monoclonal Ab)