Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Year 2 Clinical > Bone Health and Osteoporosis > Flashcards

Bone Health and Osteoporosis Flashcards

(75 cards)

Start Studying
1
Q

Definition of osteoporosis?

A

Progressive systemic skeletal disease characterised by low bone mass and micro-architectural bone tissue deterioration

There is a consequent increase in bone fragility and fracture susceptibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Common fracture sites in the skeleton?

A
  • Neck of femur (incidence rises dramatically when >70)
  • Vertebral body
  • Distal radius (most frequent up to the age of 70)
  • Humeral neck
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Morbidity and mortality assoc. with hip fractures?

A

1/2 of patients lose independence

1/5 die within a year of their fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Occurrence of osteoporotic fractures in women?

A

Majority of hip fractures occur in women >75 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Reason for women suffering more osteoporotic fractures?

A

Women have lower peak bone mass

AND

Accelerated loss of bone during the menopause

AND

Increased longevity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Presentation of vertebral fractures?

A

Many present “silently” (with no symptoms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the domino fracture effect

A

A vertebral fracture increases the risk of kyphosis

Also, if a patient has had 1 fracture, they have an increased risk of another fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the domino fracture effect

A

A vertebral fracture increases the risk of kyphosis

Also, if a patient has had 1 fracture, they have an increased risk of another fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does remodelling of bone occur?

A

Bone undergoes a continual remodelling cycle at distinct sites (BONE REMODELLING UNITS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Purpose of bone remodelling?

A

10% of the adult skeleton is remodelled every year, which contributes to:
• Calcium homeostasis
• Skeletal repair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Process of bone remodelling?

A

Beginning of cycle:
• Osteoclasts appear on a previously inactive surface and begin to resorb bone

They are then replaced with osteoblasts that fill the cavity, by laying down OSTEOID; this is MINERALISED, to form new bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Main problem with bone remodelling in osteoporosis?

A

There is a relative or absolute increase in resorption over formation; this leads to increased bone loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Structure when osteoporotic bone loss occurs?

A

Osteoporotic bone has:
• Loss of bone
• Large spaces
• Breaks in the microscopic architecture (overall weakened bone that fractures easily)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Regulation factors of peak bone mass?

A
  • Genetics (most important factor)
  • Body weight (part. being underweight)
  • Sex hormones (oestrogen; post-menopause acceleration of bone loss)
  • Diet
  • Exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Regulating factors of bone loss?

A
  • Sex hormone deficiency
  • Body weight
  • Genetics
  • Diet
  • Immobility
  • Diseases
  • Drugs, e.g: steroids, aromatase inhibitors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Age at which peak bone mass is reached?

A

Bone mass increases in men and women until a peak is attained, at ~30 years

This is the consolidated and maintained until the patient reaches 40

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Age at which bone mass starts to decrease?

A

In both sexes, slow rate of bone loss starts at 40 years; but, in post-menopausal women, there is accelerated bone loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which patients with are targeted with therapeutic intervention?

A

At those with high risk of low impact fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Non-modifiable clinical risk factors for fragility fracture?

A

Age, gender and ethnicity

Previous fracture

FH

Early menopause (≤ 45 years)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Modifiable clinical risk factors for fragility fracture?

A

BMD (bone mineral density)

Alcohol and smoking

Weight

Physical inactivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Other clinical risk factors for fragility fracture?

A

Co-morbidities

Pharmacological risk factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Use of the WHO fracture risk calculator (FRAX)?

A

Allows calculation of absolute risk, by incorporating additional risk factors (rather than just BMD)

It produces a prediction of the 10 year risk of major osteoporotic fracture or hip fracture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Advantages of FRAX?

A

Freely available (internet)

Calculates 10 year absolute risk of hip or major osteoporotic fracture

Can be used with or without BMD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Questions asked in FRAX)

A
  • Age
  • Gender
  • BMI
  • Previous fracture
  • Smoking
  • Alcohol ≥3 u/d
  • Steroids
  • RA, diabetes, OI, untreated hyperthyroidism, hypogonadism, premature menopause, malnutrition, malabsorption, chronic liver disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Disadvantages of FRAX?
Underestimates vertebral fracture risk Same level of risk assigned to all secondary causes Dichotomised variables smoking/alcohol
26
Advantages of Qfracture?
Freely available (internet) More variables included, e.g: dementia, PD, medications Hx of falls or resident in nursing homes Smoking and alcohol can be given in quantities Can use variable time for absolute risk
27
Advantages of Qfracture?
Does not inc. BMD, when available
28
Who should have risk factor assessment?
Anyone >age 50 with risk factors Anyone <50 years with very strong clinical risk factors: • Early menopause • Glucocorticoids
29
When should a patient be referred for a DEXA scan?
Any patient with a 10 year risk assessment of at least 10%, for any osteoporotic fracture
30
How is bone density assessed?
Bone mineral density predicts fracture risk INDEPENDENT of any other risk factors DEXA scan are usually used to measure BMD
31
Interpreting DEXA scan results?
Normal: • BMD within 1 SD of the young adult reference mean Osteopenia (low bone mass) • BMD >1 SD below the young adult mean but <2.5 SD below this value Osteoporosis: • BMD ≥ 2.5 SD below the young adult mean Severe osteoporosis: • BMD ≥2.5 SD below the young adult mean with fragility fracture
32
If the patient is <20 years old, how is the DEXA scan result reported?
Only the Z score is reported
33
Relationship between BMD and fracture risk?
As BMD decreases, verterbal fracture risk increases
34
Ix for osteoporosis?
U&Es, LFTs, FBC, PV and TSH Bone biochemistry ``` Consider doing: • Protein electrophoresis • Urinary Bence Jones proteins (indicate multiple myeloma, a bone marrow malignancy, which can cause osteoporosis) • Coeliac antibodies • Testosterone • 24-OH vitamin D • PTH ```
35
Secondary causes of osteoporosis?
Endocrine: • Hyperthyroidism • Hyperparathyroidism • Cushing's disease ``` GI: • Coeliac disease • IBD • Chronic liver disease • Chronic pancreatitis ``` Respiratory: • CF • COPD Renal: • Chronic kidney disease
36
Lifestyle advice for Mx of osteoporosis?
High intensity strength-training and low-impact weight bearing exercise (standing with one foot always on the floor) Avoid smoking and excess alcohol Prevent falling
37
Calcium in the diet for Mx of osteoporosis?
700 mg of Ca2+ is required in most patients; post-menopausal women should aim their dietary intake at 1000 mg of Ca2+ per day
38
Portions of foot required for osteoporosis?
For 700 mg, 2-3 portions form milk and dairy) For 100mg, 3-4 portions of calcium-rich foods ``` Non-dairy sources: • Bread and cereals (fortified) • Fish with bones • Nits • Green vegetables • Beans ```
39
Pharmacological treatment of osteoporosis?
Calcium & vitamin D supplementation Bisphosphonate Denosumab Teriparatide Strontium Ranelate HRT SERMS (selective oestrogen receptor modulators) Testosterone
40
When is calcium and vitamin D replacement used for osteoporosis?
R-calcium and vitamin D supplementation can be used to reduce risk of non-vertebral fractures in patients at high risk of deficiency due to insufficient diet or limited sunlight exposure If dietary calcium is adequate (>700 mg daily), Vitamin D only may be preferred as the osteoporosis treatment adjunct
41
Cautions with calcium supplementation?
Should not be taken within 2 hours of oral bisphosphonates
42
When is a patient automatically considered to be at risk of vitamin D deficiency?
If low exposure to sun (cultural or housebound)
43
Examples of bisphonphonates?
Alendronate Risedronate Zoledronic acid
44
Uses of bisphosphonates?
Prevent bone loss at sites vulnerable to osteoporosis Reduce risk of hip and spinal fracture; reduce risk of fragility fracture by ~50% in patients with post-menopausal osteoporosis
45
Mechanism of action of bisphosphonates?
Anti-resorptive agent that are analogues of pyrophosphate They adsorb onto bone within the matrix and are ingested by osteoclasts, leading to cell death (so bone resorption is inhibited) Filling of resorption sites with new bone increases BMD
46
Duration of bisphosphonate therapy?
For 5 years (if a vertebral fracture, 10 years) After stopping, drugs stay in bone and the effect remains for 2-3 more years
47
Potential side effects of bisphosphonate therapy?
Osteonecrosis of the jaw Oesophageal carcinoma Atypical fractures
48
Administration of Zoledronic acid?
Once yearly IV infusion for 3 years: | • 5mg in 100ml of NaCl is given over 15 minutes
49
Potential side effect of Zoledronic acid and treatment?
Acute phase reaction (fever, flu-like, night sweats, rigors, diffuse MSK pain, GI effects, and eye inflammation) Treat with paracetamol
50
What is Denosumab?
Fully human monoclonal Ab
51
Mechanism of action of Denosumab?
Targets and binds, with high affinity and specificity, to RANKL (receptor activator of nuclear factor-kB ligand) Prevents receptor activation (RANK), which: • Inhibits development and activity of osteoclasts • Decrease bone resorption • Increase bone density
52
Administration of Denosumab?
S/C injection every 6 months
53
Potential side effects of Denosumab?
Hypocalcaemia Eczema Cellulitis There are no contraindication in severe renal impairment
54
What is Strontium Ranelate?
Anti-resorptive agent that is 3rd line for fracture risk reduction It is not recommended when there is an alternative osteoporosis treatment available
55
Contraindications with strontium ranelate?
``` Hx of: • Thromboembolic disease • IHD • Peripheral arterial disease • Uncontrolled hypertension ```
56
What is Teriparatide?
Recombinant PTH that stimulates bone growth (rather than reducing bone loss), i.e: it is an anabolic agent
57
When is Teriparatide used?
>65 years with T score < -4 T score of – 3.5 with >2 fractures Aged 55-64 years with a T score of -4 or below with >2 fractures (plus intolerant/unsatisfactory response to oral agents)
58
When to pharmacologically treat a patient with osteoporosis?
In most patients, consider treatment with anti-resorptive therapy when: • T-score ≤ -2.5 If ongoing steroid requirement of ≥ 7.5mg prednisolone for 3 months/more OR if there is a prevalent vertebral fracture: • Consider treatment with T-score < -1.5
59
Direct effects of corticosteroids on bone?
* Reduction of osteoblast activity and lifespan * Suppression of replication of osteoblast precursors * Reduction in calcium absorption
60
Indirect effect of corticosteroids on bone?
Inhibition of gonadal and adrenal steroid production
61
Effects of glucocorticoids on calcium metabolism?
Kidney Gut (reduced Ca2+ absorption) Bone (decreased matrix synthesis resorption) Pituitary
62
Fracture risk with steroids?
Is dose-dependent; there is a rapid loss of BMD in the 1st 6 months (partially reversible)
63
What is Paget's disease of bone?
Excessive breakdown and formation of bone, followed by disorganized bone remodeling, i.e: there is abnormal osteoclastic activity that is then followed by increased osteoblastic activity
64
Aetiology of Paget's disease of bone?
Uncertain but may be a viral, environmental or biochemical trigger in a genetically susceptible individual
65
Consequences of Paget's disease of bone?
Abnormal bone structure with reduced strength, so increased fracture risk
66
Sites inv. with Paget's disease of bone?
Monostotic (single site) or polyostotic (multiple sites) Predominantly affects long bones, pelvis, lumbar spine and skull; does not affect fingers and toes (SPARING)
67
Occurrence of Paget's disease of bone?
Rare <40 years and incidence increases with age
68
Presentation of Paget's disease of bone?
Bone pain, deformity, deafness or compression neuropathies
69
Complication of Paget's disease of bone?
Osteosarcoma (rare)
70
Ix and diagnosis of Paget's disease of bone?
May be incidental finding on X-ray or isolated raised Alk Phos Diagnose with: • X-ray • Isotope bone scan shows distribution • Raised alkaline phosphatase with normal LFT
71
Treatment of Paget's disease of bone?
With bisphosphonates, if pain not responding to analgesia
72
What is osteogenesis imperfecta?
Rare group of genetic disorders mainly affecting bone, with at least 8 types of varying severity Most are secondary to mutations in type 1 collagen genes (COL1A1, COL1A2); also, most show autosomal dominant inheritance
73
Types of osteogenesis imperfecta and presentation?
Type I (mild) - may not present till adulthood Types III and IV (very severe) Type II (neonatal lethal - they have fractures in utero) More severe forms present with childhood fractures
74
Causes of childhood fractures?
Most common is trauma If "no Hx of trauma", consider NAI Rare cause is osteogenesis imperfect
75
Treatment of osteogenesis imperfecta?
No cure but can use: • Fracture fixation • Surgery to correct deformities • Bisphosphonates

Year 2 Clinical (119 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions