Bone Diseases

Question 1

What is arthritis?

Answer 1

Inflammation of joints

Question 2

What is arthrosis?

Answer 2

Non-inflammatory joint disease

Question 3

What is arthralgia?

Answer 3

Joint pain

Question 4

What makes up bone?

Answer 4

Mineralised connective tissue
Calcium
Phosphate
Vitamin D

Question 5

Describe the role of parathyroid hormone?

Answer 5

Maintains serum calcium level - raised if calcium levels fall
Increases calcium release from bone
Reduces renal calcium excretion

Question 6

Describe serum calcium in hypoparathyroidism

Answer 6

Low serum calcium

Question 7

Describe serum calcium in hyperparathyroidism

Answer 7

Primary - gland dysfunction results in high serum calcium
Secondary - caused by low serum calcium
Both result in increased bone resorption

Question 8

Describe the action of vitamin D

Answer 8

Results in absorption of calcium

Question 9

What are the problems with vitamin D?

Answer 9

Low sunlight exposure in Scotland
Poor GI absorption if nutrition is poor or in those with small intestinal disease
Drug interactions - carbamazepine and phenytoin

Question 10

What is osteomalacia?

Answer 10

Poorly mineralised osteoid matrix
Poorly mineralised cartilage growth plate

Question 11

What is osteoporosis?

Answer 11

Loss of mineral and matrix leads to reduced bone mass

Question 12

What are the different types of osteomalacia?

Answer 12

If during bone formation - rickets
If after bone formation - osteomalacia
Both related to calcium deficiency

Question 13

What investigations are done for osteomalacia?

Answer 13

Serum calcium - decreased
Serum phosphate - decreased
Alkaline phosphatase - very high
Plasma creatine - ??
Plasma parathyroid hormone - ??

Question 14

What effects does osteomalacia have on bone?

Answer 14

Bones bend under pressure
Bones ache to touch
Vertebral compression in adults

Question 15

What are the effects of hypocalcaemia?

Answer 15

Muscle weakness
Trousseau and Chvostek signs positive
Carpal muscle spasm
Facial twitching

Question 16

How is osteomalacia managed?

Answer 16

Correct the cause:
Malnutrition - control GI disease
Sunlight exposure - 30 mins 5x weekly
Dietary vitamin C

Question 17

Give some risk factors of osteoporosis

Answer 17

Female sex
Family history
Caucasian and Asian woman
Smoking
Excessive alcohol use

Question 18

Who is affected by osteoporosis?

Answer 18

15% women age 50
30% women age 70
40% woman aged 80

Question 19

Why are women affected more than men by osteoporosis?

Answer 19

Males have a higher peak bone mass
Oestrogen withdrawal increases bone mass loss rate in women

Question 20

What are the effects of osteoporosis?

Answer 20

Increased bone fracture risk
Height loss from vertebrae compression
Lifetime risk of hip fracture

Question 21

What are the average outcomes of osteoporosis related hip fracture?

Answer 21

20% increase in 5 year mortality
40% unable to walk unaided
60% unable to live independently

Question 22

What can be done for osteoporosis prevention?

Answer 22

Build maximal peak bone mass - exercise and high dietary calcium intake
Reduce rate of bone mass loss
Consider osteoporosis prevention drugs - bisphosphonates

Question 23

How is hormone replacement therapy used to treat osteoporosis?

Answer 23

Oestrogen only
Reduces osteoporosis risk but increases risk of breast cancer, endometrial cancer, and DVT

Question 24

Give examples of bisphosphonates

Answer 24

Non-Nitrogenous - etidronate, clodronate
Nitrogenous - pamidronate, neridronate

Question 25

How effective are bisphosphonates?

Answer 25

Reduce vertebral fracture risk by 50%
Reduce other fractures by 30-50%