Bone physiology

Question 1

True or False

One vertebral fracture will lead to another

Answer 1

True

Question 2

What do osteoclasts do?

Answer 2

Resorb bone

Question 3

What do osteoblasts do?

Answer 3

Put down osteoid to form new bone

Question 4

Who should be assessed using the risk factor assessment? (2)

Answer 4

Anyone over 50 with risk factors

Anyone under 50 with an early menopause or on steroids

Question 5

When should a DEXA scan be requested?

Answer 5

10 year risk assessment of at least 10%

Question 6

In a DEXA scan, which value is the most important?

Answer 6

T value

Question 7

What does the T value have to be to be classified as osteoporosis?

Answer 7

More than -2.5

Question 8

What is a Z score?

Answer 8

Age matched so compares with age and size

Question 9

When are Z scores used?

Answer 9

If younger than 20

Question 10

What class of drug is given if osteoporosis is diagnosed?

Answer 10

Bisphosphonate

Question 11

What are examples of bisphosphonates?

Answer 11

Alendronic or risedronic acid

Question 12

When is zolendronic acid given?

Answer 12

If DEXA intolerable

Question 13

What is given in severe spinal osteoporosis?

Answer 13

Teriparatide

Question 14

If osteopenia is diagnosed what is done?

Answer 14

Lifestyle advice e.g. smoking, alcohol, weight bearing exercise, falls advice
DEXA reassessment

Question 15

True or False

Post-menopausal women should increase their dairy intake

Answer 15

True

Question 16

How do bisphosphonates work?

Answer 16

Apoptosis of osteoclasts so inhibit bone resorption

Question 17

What are long term potential side effects of bisphosphonates?

Answer 17

Osteonecrosis of jaw

Oesophageal Ca

Question 18

How is zolendronic acid given?

Answer 18

Once yearly IV infusion

Question 19

When is denosumab given?

Answer 19

If bisphosphonates intolerable.

Question 20

How should alendeonic acid be given?

Answer 20

Tablet, 30 minutes before food and don’t lie down for half an hour after

Question 21

When should alendronic acid be stopped?

Answer 21

Oesophagitis or ulcers

Question 22

What are common side effects of alendronic acid?

Answer 22

Abdo pain
Nausea
dyspepsia
GI side effects

Question 23

How does denosomuab work?

Answer 23

Monoclonal Ab that binds to RANKL

Question 24

What is RANKL?

Answer 24

Receptor activator of nuclear factor kB ligand

Question 25

How does activating RANKL prevent osteoporosis?

Answer 25

Inhibits osteoclasts and decreases bone resorption

Question 26

How is denosomuab given?

Answer 26

Subcut injection 6 monthly

Question 27

Why is strontium not recommended as 1st line?

Answer 27

Fracture reduction is slightly less and dangerous in heart disease

Question 28

Where does Paget's disease affect?

Answer 28

Long bones Pelvis Lumbar spine Skull

Question 29

What is Paget's disease?

Answer 29

Increased osteoclast activity with abnormalities. Reduced strength

Question 30

What is a complication of Paget's disease?

Answer 30

Osteosarcoma

Question 31

What symptoms may present with Paget's?

Answer 31

Often asymptomatic but bone pain or deformity and deafness

Question 32

How is Paget's diagnosed?

Answer 32

XR | Increased alk phos

Question 33

How is Paget's treated?

Answer 33

Bisphosphonates

Question 34

Which defect causes osteogenesis imperfecta?

Answer 34

COL1A1/2 | Autosomal dominant

Question 35

What is associated with osteogenesis imperfecta?

Answer 35

Blue sclerae | Dentinogenesis imperfecta

Question 36

Which receptor on the parathyroid is for calcium?

Answer 36

Ca sensitive receptor

Question 37

What kind of receptor is CaSR?

Answer 37

G protein coupled

Question 38

How is vitamin D stored in the liver?

Answer 38

Cholecaliferol

Question 39

What does the liver convert it to?

Answer 39

25-hydroxycholecaliferol

Question 40

What does the kidney turn it into?

Answer 40

1,25-hydroxycholecaliferol

Question 41

What are symptoms of acute hypercalcaemia?

Answer 41

Thirst Dehydration Polyuria Confusion

Question 42

What are symptoms of chronic hypercalcaemia?

Answer 42

Myopathy Fractures Depression Abdo pain

Question 43

What are major causes of hypercalcaemia?

Answer 43

Primary hyperparathyroidism | Malignancy

Question 44

What drugs can cause hypercalcaemia?

Answer 44

Vitamin D | thiazides

Question 45

What will blood results be for 1o hyperparathyroidism?

Answer 45

Raised serum Ca Raised serum PTH Increased urine Ca excretion

Question 46

What other serum protein is important for diagnosing malignancy?

Answer 46

Alkaline phosphate (raised in malignancy)

Question 47

What is the treatment for acute hypercalcaemia?

Answer 47

Fluids Loop diuretics once rehydrated Bisphosphonates will lower Ca

Question 48

How is 1o primary hyperparathyroidism managed?

Answer 48

Surgery or nothing

Question 49

When should surgery for 1o hyperparathyroidism be indicated?

Answer 49

If end organ damage e.g. renal stones, osteoporosis, gastric ulcers or renal disease Or if calcium is v high (>2.85)

Question 50

What is 2o hyperparathryoidism?

Answer 50

Physiological response to low Ca | PTH raised

Question 51

What is 3o hyperparathyroidism?

Answer 51

Overactive PTH after many years of 2o

Question 52

Which genetic syndromes are closely linked with hyperparathyroidism?

Answer 52

MEN1/2

Question 53

What is FHH?

Answer 53

Familial hypocalciuric hypocalcaemia

Question 54

What signs will be present in FHH?

Answer 54

Low Ca urine | Hypercalcaemia

Question 55

How does PTH work on the gut?

Answer 55

Causes it to absorb Ca and therefore increased serum Ca levels

Question 56

In which fish is vitamin D high in?

Answer 56

Herring

Question 57

What are the symptoms of hypocalcaemia?

Answer 57

Paraesthesia in extremities and perioral tetany and cramps Fatigue and myopathy Long QT on ECG

Question 58

What are the causes of hypocalcaemia?

Answer 58

Hypoparathyroidism Vitamin D deficiency renal failure Pancreatitis

Question 59

What is the treatment for acute hypocalcaemia?

Answer 59

10ml 10% IV calcium gluconate over 10 mins

Question 60

In what congenital condition is the parathyroid gland underachieve?

Answer 60

DiGeorge syndrome

Question 61

What are the other features of DiGeorge syndrome?

Answer 61

``` Cardiac abnormalities Abnormal facies Thymus aplasia Cleft palate Hypoparathyroidism/hypocalcaemia Chromosome 22 ```

Question 62

What is the long term management of hypoparathyroidism?

Answer 62

Calcium supplement daily | Vitamin D tablet

Question 63

Why can hypomagnaeseamia cause low calcium?

Answer 63

Ca release is Mg+ dependent

Question 64

What causes hypomagnaeaemia ?

Answer 64

Alcohol Thiazides PPI

Question 65

What is pseudohypoparathyroidism?

Answer 65

Genetic defect of GNAS1 which means that PTH is resisted

Question 66

What are symptoms of pseudohypoparathyroidism?

Answer 66

Obesity Learning disabilities Brachdactyly of 4th metacarpal Hypocalcaemia

Question 67

What is pseudo-pseudohypoparathyroidism?

Answer 67

Same but with normal Ca

Question 68

What can cause rickets?

Answer 68

Coeliac disease Liver disease Chronic renal failure

Question 69

True or False | Alk phos is raised in Osteomalacia

Answer 69

True