Bone disease

Question 1

Define arthritis

Answer 1

Inflammation of the joints.

Question 2

Define arthrosis

Answer 2

Non-inflammatory joint disease

Question 3

Define arthralgia

Answer 3

Joint pain

Question 4

What nutrients are required in bone turnover cycle?

Answer 4

Calcium
Phosphate
Vit D

Question 5

Briefly describe he bone turnover cycle.

Answer 5

Osteoclasts resorb old bone and are then replaced by osteoblasts which deposit an osteoid matrix which is mineralised to form bone.

Question 6

Functions of calcium

Answer 6

Bone mineralisation
Regulation of nervous system and brain chemistry through calcium channels
Regulation of muscle tone

Question 7

Function of PTH

Answer 7

Regulates serum calcium level (if calcium levels fall, PTH increased).

Question 8

What is hypoparathyroidism?

Answer 8

Insufficient PTH produced
Results in low serum calcium.

Question 9

What is hyperparathyroidism?

Answer 9

Overproduction of PTH.
Results in increased bone resorption.

Question 10

Primary hyperparathyroidism

Answer 10

Gland dysfunction - tumour.
Results in high serum calcium.

Question 11

Secondary hyperparathyroidism

Answer 11

Results in low serum calcium.

Question 12

Causes of low vitamin D

Answer 12

Low sunlight exposure
Poor GI absorption - poor nutrition, small intestinal disease (malabsorption)
Drug interactions with vitamin D synthesis - some anti- epileptic drugs e.g. carbamazepine, phenytoin

Question 13

Define osteomalacia

Answer 13

Normal amounts of poorly mineralised osteoid matrix (soft bone)

Question 14

Rickets

Answer 14

Osteomalacia during bone formation (in children). Usually due to low vitamin D.

Question 15

Osteomalacia investigations

Answer 15

Decreased serum calcium and phosphate.
Very high alkaline phosphatase (measure of bone turnover).

Question 16

Signs and symptoms of osteomalacia

Answer 16

Bone effects:
Bones ache to touch
‘Bow legs’

Hypocalcaemia effects:
Muscle pain and weakness
Muscle cramps
Positive Trousseau & Chvostek signs = Facial twitching and carpal muscle spasm

Question 17

Management of osteomalacia

Answer 17

Correct the cause:
Malnutrition, control GI disease
Sunlight exposure (30mins x 5 weekly)
Dietary vitamin D supplements

Question 18

Define osteoporosis

Answer 18

A reduced quantity of normally mineralised bone.
Age-related change - inevitable.

Question 19

Osteoporosis risk factors

Answer 19

Female sex
Oestrogen & testosterone deficiency
Cushing’s syndrome
Genetic - family history, early menopause
Patient factors - inactivity, smoking, alcohol, poor dietary calcium
Drugs - steroids, anti-epileptics

Question 20

Effects of osteoporosis

Answer 20

Increased bone fracture risk (risk of hip fracture)
Kyphosis (bending forward of spine) & scoliosis
Back pain - Nerve root compression

Question 21

Osteoporosis prevention

Answer 21

Build maximal peak bone mass via exercise and high dietary calcium intake.
Reduce rate of bone mass loss by maintaining calcium intake throughout life.
Reduce hormone related effects - oestrogen hormone replacement therapy.
Consider osteoporosis prevention drugs - bisphosphonates

Question 22

Action of bisphosphonates

Answer 22

Act by preventing osteoclast action by poisoning the osteoclasts and reducing their numbers.
- alendronate
- ibandronate
- zoledronate

Question 23

Effects of oestrogen hormone replacement therapy

Answer 23

Reduces osteoporosis risk
Increases breast cancer risk
Increases endometrial cancer risk - combine with progestogen in pt’s. who have not had a hysterectomy
Increases DVT risk