disorders of bone health including osteopersosis

Question 1

what is osteoporosis?

Answer 1

-progressive systemic skeletal disease characterised by low bone mass and micro architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture

Question 2

where does the bone remodelling cycle occur?

Answer 2

-at distinct sites called bone remodelling units

Question 3

what process contributes to calcium homeostasis and skeletal repair?

Answer 3

the continual bone remodelling cycle

Question 4

what are the 3 main types of bone cells?

Answer 4

• osteoclasts
• osteoblasts
• osteocytes

Question 5

what are osteoclasts?

Answer 5

-multinucleated cells responsible for bone reabsorption, derived from haematopoietic progenitors

Question 6

what are osteoblasts?

Answer 6

-mononucleated cells derived from mesenchymal cells in the bone marrow stroma, responsible for bone formation

Question 7

what are osteocytes?

Answer 7

-primary cell of mature bone and most common type of bone cell, derived from the osteoblasts which become buried in bone matrix

Question 8

what are the three phases of bone remodelling in a bone remodelling unit?

Answer 8

• resting phase
• active bone resorption
• bone formation

Question 9

what bone cell is responsible for active bone resorption?

Answer 9

osteoclasts

C=cut

Question 10

what is bone resorption?

Answer 10

-destruction of bone tissue, promoting bone loss

Question 11

what bone cell is responsible for bone formation?

Answer 11

-osteoblasts

B=build

Question 12

describe the bone microarchitecture at a healthy 20 year old

Answer 12

• good strong trabecular

- healthy bone

Question 13

describe the bone microarchitecture of a 50 year old

Answer 13

-decrease in trabecular thickness which is more pronounced for non load-bearing horizontal trabeculae

Question 13

describe the bone microarchitecture of a 50 year old

Answer 13

-decrease in

Question 14

describe bone microarchitecture in 80 years?

Answer 14

-decrease in number of connections between vertical trabeculae which causes a decrease in trabeculae strength

Question 15

what are bone trabeculae?

Answer 15

-highly porous forms of bone tissue that are organised into a network of interconnected rods and plates

Question 16

what occurs to the tubercular in osteoporotic bone?

Answer 16

-they’re a lot weaker and there’s breaks between them

Question 17

what factors can lead to bone loss?

Answer 17

• sex hormone deficiency
• changes in body weight
• genetics
• diet
• immobility
• disease
• drugs especially glucocorticoids and aromatase inhibitors

Question 18

what are some non-modifiable risks of a fragility fracture?

Answer 18

• age
• gender
• ethnicity
• previous fracture
• family history
• menopause <45

Question 19

what are some modifiable risks of a fragility fracture?

Answer 19

• BMD
• alcohol
• weight
• smoking
• physical inactivity
• drugs

Question 20

what is used to determine fracture risk?

Answer 20

QFracture score

Question 21

who would you do a risk factor assessment on?

Answer 21

> 50 with risk factors

<50 with very stron clinical factors:

• early menopause
• glucocorticoids

Question 22

when to refer for DXA (dual energy Xray)?

Answer 22

-patients >50 years with low trauma fracture

• patients at increased risk of fracture based on risk factures (calculated using risk essessment tool e.g. FRAX or Q fracture)
• this would have to be >10% risk of fracture over 10 years

Question 23

what is the most widely used method of measuring bone mass density?

Answer 23

DEXA scans

Question 24

what is the T score?

Answer 24

way of measuring risk of osteoperosis -compare the patients BMD with an estimate of what their BMD would've been when they were a young adult (at peak bone density)

Question 25

what is a normal BMD?

Answer 25

within 1 SD (standard deviation) of the young adult reference mean

Question 26

what would be classed as osteopenia (low bone mass)?

Answer 26

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

Question 27

what would be classed as osteoporosis?

Answer 27

BMD> or equal to 2.5 SD below the young adult mean

Question 28

what would be classed as severe osteoporosis?

Answer 28

BMD equal to or over 2.5 SD below the young adult mean fragility with fragility fracture

Question 29

what is used to class BMD if a patient is <20?

Answer 29

Z score report

Question 30

what is the Z score?

Answer 30

the average bone density of an aged match group of patients used in patients <20

Question 31

what is the relationship between T score and risk of fracture?

Answer 31

- for every additional SD below normal there is a doubling of fracture risk - As the T score increases the fracture risk increases

Question 32

what are some endocrine secondary causes of osteoporosis?

Answer 32

- hyperthyroidism - hyperparathyroidism - cushings disease

Question 33

what are some GI secondary causes of osteoperosis?

Answer 33

- coeliac - IBD - chronic liver disease - chronic pancreatitic

Question 34

what are some resp secondary causes of osteoperosis?

Answer 34

- CF | - COPD

Question 35

what are some renal secondary causes of osteoperosis?

Answer 35

-chronic kidney disease

Question 36

what investigations are done for a patient with suspected osteoperosis?

Answer 36

- U + Es - LFTs - FBC - PV - TSH levels - bone biochemistry

Question 37

what is some lifestyle advice for patients diagnosed with osteoporosis?

Answer 37

- High intensity strenght training - low impact weight bearing excercise (standing, one foot always on floor) - avoid of excess alcohol - smoking cessation - fall prevention

Question 38

what is some diet advice for patients with osteoporosis?

Answer 38

- 700mg of calcium (2-3 portions from milk and dairy food groups) - post menopausal women aim dietary intake 1000mg calcium per (3-4 portion calcium rich foods) - bread and cereal - fish with bones - nuts - green vegetables - beans

Question 39

what is the drug treatment for osteoperosis?

Answer 39

- calcium and vitamin D - biphsophonates= 1st line - denosumab - teriparatide - romosozumab - HRT - SERMs (selective estrogen receptor modulators) - testosterone

Question 40

when is osteoporosis treated?

Answer 40

-majority of patients, consider treatment with antiresorptive therapy when T score /=7.5mg prednisolone for 3 months or more if there is a prevalent vertebral fracture, consider treatment with T score

Question 41

what drug is used if patients are intolerant to biphosphonates or are high risk?

Answer 41

- Zoledronic Acid (given IV infusion for 3 years) | - Denosumab

Question 42

what are the side effects of donsumab?

Answer 42

- hypocalcaemia - eczema - cellulitis

Question 43

when is donsumab contraindicated?

Answer 43

severe renal impairement

Question 44

when is Teriparatide recommended?

Answer 44

-patients with most severe osteoperosis especially patients with non trauma vertebral fractures in postmenapausal women

Question 45

when is romosozumab recommended?

Answer 45

recommended for postmenopausal women with severe osteoporosis who have had a fragility fracture and are at imminent risk of further fracture (24 months)

Question 46

what are the direct effects that corticosteroids have on bone?

Answer 46

- reduction of osteoblast activity and lifespan - suppression of replication of osteoblasts precursors - reduction in calcium absorptions

Question 47

what is an indirect effect of corticosteroids and bone?

Answer 47

-inhibition of gonadal and adrenal steroid production

Question 48

what is Paget's disease?

Answer 48

- abnormal osteoclastic activity followed by increase osteoblastic activity - abnormal bone structure with reduced strength and increased fracture risk

Question 49

what bones does Paget's usually affect?

Answer 49

- long bones - pelvis - lumbar spine - skull