Osteoperosis

Question 1

Rickets/Osteomalacia (2)

Answer 1

Vitamin D deficiency leading to softening of bones

Because of inadequate bone mineralisation

Question 2

Why do osteoporotic fractures increase during winter?(2)

Answer 2

Lower sunlight exposure

Reduced vitamin D synthesis

Question 3

Osteoporosis (3)

Answer 3

Low bone mass
Deterioration of bone tissue
High risk of fracture

Question 4

Alcoholism (4)

Answer 4

Suppresses proliferation of osteoblasts which inhibits born formation
May increase osteoclastogenesis
Reduced bone mineral density
Increased risk of falling

Question 5

Reproductive cycle and risk of osteoporosis

Answer 5

Early menopause or late menarche increase risk

Question 6

Types of bone material (2)

Answer 6

Cortical

Trabecular

Question 7

Most common bone material

Answer 7

Cortical (70-80%)

Question 8

What is the majority of skeleton made from?

Answer 8

Inert matrix materials

Question 9

Inert matrix materials (3)

Answer 9

Calcium
Phosphate
Collagen fibres

Question 10

When does the deposits of matrix occur?

Answer 10

Childhood

Question 11

What is peak bone mass?

Answer 11

Maximum bone mineral mass attained

Question 12

Role of osteoblasts

Answer 12

Bone mineral deposition

Question 13

Role of osteoclasts

Answer 13

Bone mineral loss

Question 14

Growth hormone

Answer 14

Increases osteoblasts

Question 15

Vitamin D3 effects (5)

Answer 15

Increases calcium absorption
Increases calcium uptake
Increases calcium bone deposition

Also increases osteoclasts
Results in calcium bone loss

Question 16

Calcitonin

Answer 16

Inhibits osteoclasts

Question 17

Sex steroids

Answer 17

Increases osteoblasts

Increased deposition

Question 18

Parathyroid hormone (4)

Answer 18

Inhibits sex steroids (prevents osteoblasts)

Increases osteoclasts
Bone loss
Calcium bone loss

Question 19

______ bone remodels ____ times faster than _____ bone

Answer 19

Trabecular
8
Cortical

Question 20

Which bone regions are more vulnerable to bone loss?

Answer 20

Trabecular

Question 21

Role of VDR (2)

Answer 21

Role in controlling calcium status

Variants linked to lower BMD

Question 22

Oestrogen receptor (2)

Answer 22

Key role in oestrogen effects on bone tissue

Variants may be linked to BMD

Question 23

Collagen 1 alpha 1 gene (2)

Answer 23

Collagen 1 alpha is the main protein in bone

Abnormal gene forms may alter bone and reduce strength

Question 24

What percentage of gene variation may related to BMD

Answer 24

60-90%

Question 25

Importance of childhood

Answer 25

Maximising peak bone mass

Question 26

Importance of young adulthood

Answer 26

Maintain bone mass

Question 27

Importance of older adulthood

Answer 27

Minimise bone loss

Question 28

Calcium (4)

Answer 28

Benefits bone health at any stage Higher intakes increase bone mass However does but reduce the risk of fractures Benefits of supplements disappear rapidly once supplementation ends

Question 29

Effects of vitamin D supplementation (2)

Answer 29

Reduces risk of fractures at high doses | Slows bone mineral loss in individuals with low calcium status

Question 30

Caffeine and BMD (5)

Answer 30

Associated with lower BMD Promotes excretion of calcium Reduced calcium uptake from gut In post menopausal women high intakes may be related to increased risk of fractures VDR genotype dependent

Question 31

Phytoestrogens (5)

Answer 31

Plant derived agents with similar structure to steroids Can bind to oestrogen receptors and produce biological effects May be safe alternative to HRT post menopause May prevent bone loss in women However studies have shown little effect

Question 32

Equol (4)

Answer 32

Produced by gut microflora after consumption of phytoestrogens Depending on phenotype This conversion more prevalent in vegetarians Has enhanced effects at oestrogen receptors

Question 33

Protein and osteoporosis (4)

Answer 33

Excessively high intakes may promote calcium excretion and bone loss Protein promotes muscle strength and reduces risk of falls Moderate intakes increases BMD depending on calcium status However elderly are at the greatest risk of PEM in developed countries