disorders of bone health

Question 1

what are osteoblasts?

Answer 1

bone forming cells

Question 2

what are osteoclasts responsible for?

Answer 2

bone breakdown/reabsorption

Question 3

what are osteocytes?

Answer 3

mature bone cells within the bone matrix, help to maintain bone and act as mechanosensors

Question 4

which drugs can cause bone mass loss?

Answer 4

glucocorticoids

Question 5

what are the common fracture sites?

Answer 5

Neck of femur
Vertebral body
Distal radius
Humeral neck

Question 6

what are the non modifiable risk factors for fractures?

Answer 6

Age
Gender
Ethnicity
Previous fracture
Family history
Menopause ≤ 45 years
Co-existing diseases

Question 7

what are the modifiable risk factors for fractures?

Answer 7

BMD (bone mineral density)
Alcohol
Weight
Smoking
Physical inactivity
Pharmacological risk factors

Question 8

who gets referred for DEXA?

Answer 8

patients over 50with low trauma fracture
people who have a risk >10% over a 10 year period

Question 9

what is the clinical range for osteopenia?

Answer 9

BMD>1 SD below young adult mean but <2.5 below this value

Question 10

what is the clinical range for osteoperosis?

Answer 10

BMD ≥ 2.5 SD below the young adult mean

Question 11

if the patient is younger than 20, which score is reported?

Answer 11

Only the Z score

Question 12

what are the secondary causes of osteoperosis?

Answer 12

endocrine eg hyperthyroidism, cushings disesase

GI eg coeliac, IBD chronic liver disease

respiratory eg COPD

chronic kidney disease

Question 13

what is the lifestyle advice for management of osteoperosis?

Answer 13

High intensity strength training
Low-impact weight-bearing exercise (standing, one foot always on the floor)
Avoidance of excess alcohol
Avoidance of smoking
Fall prevention

Question 14

what are the drug treatments for osteoperosis?

Answer 14

Calcium & vitamin D supplementation
Bisphosphonates
Denosumab
Teriparatide
Romosozumab
HRT
Testosterone

Question 15

how do biphosphonates work?

Answer 15

ingested by osteoclasts leading to cell death
thereby inhibiting bone resorption

Question 16

what are some examples of biphosphonates?

Answer 16

alendronate
risedronate

both taken 1 per week

Question 17

what are the side affects of biphosphonate therapy?

Answer 17

osteonecrosis of jaw
oesophageal Ca

Question 18

what is an alternative to biphosphonates?

Answer 18

zoledronic acids (IV done if people cant tolerate biphosphonates)
denosumab (SC monoclonal antibody)

Question 19

what are the direct effects of corticosteroids on the bone?

Answer 19

Reduction of osteoblast activity and lifespan
Suppression of replication of osteoblast precursors
Reduction in calcium absorption

Question 20

what are the indirect effects of corticosteroids on the bone?

Answer 20

inhibition of gonadal and adrenal steroid production

Question 21

what % of BMD is lost in the first 6 months of use of corticosteroids?

Answer 21

30%

Question 22

what bones does pagets disease primarily affect?

Answer 22

long bones
pelvis
lumbar spine
skull

Question 23

what causes pagets disease?

Answer 23

unknown aetiology

Question 24

how does pagets disease present

Answer 24

bone pain, deformity, deafness, compression neuropathies

Question 25

what is a rare complication of pagets disease?

Answer 25

osteosarcoma

Question 26

how is pagets treated?

Answer 26

with biphosphonates if pain not responding to analgesia?

Question 27

what happens in pagets disease?

Answer 27

Abnormal osteoclastic activity followed by increased osteoblastic activity

Question 28

what is osteogenesis imperfecta?

Answer 28

a rare group of genetic disorders mainly affecting bone

Question 29

what mutations tend to cause osteogenesis imperfecta?

Answer 29

type 1 collagen mutations (COL1A1 and COL1A2)

Question 30

what pattern of inheritance does osteogenesis imperfecta follow?

Answer 30

autosomal dominant

Question 31

what can osteogenesis imperfecta be associated with?

Answer 31

blue sclerae and dentinogenesis imperfecta