Abos - Basic Science:bone:osteoporosis

Front 1

What effect does aging have on stomach acidity?

Back 1

Decreased acidity

Front 2

What effect does the change in acidity have on calcium absorption?

Back 2

Decreased calcium absorption

Front 3

What effect does aging have on vitamin D requirements?

Back 3

Increased vitamin D requirements with age C

Front 4

ls osteoporosis a quantitative or qualitative deficiency of bone?

Back 4

Quantitative (not enough bone)
Compare to tickets (qualitative; poor quality bone)

Front 5

What are the common laboratory findings in patients with osteoporosis?

Back 5

Generally normal

Front 6

What is the definition of osteoporosis in terms of T-score?

Back 6

T-score of -2.5 or less

Front 7

What are the two indications for treatment of osteoporosis?

Back 7

T score of -2.5
History of any osteoporotic fracture

Front 8

Compare the definitions of T-score and Z-score?

Back 8

T-score is the number of standard deviations away from mean peak bone mass (comparison to 25-year-old population)
Z-score is the number of standard
deviations away from mean bone population (comparison to population of the same age as the patient)

Front 9

What two imaging modalities are most commonly used to arrive at a T-score?

Back 9

Dual-energy x-ray absorptiometry (DEXA) scan
Quantitative computed tomography (CT) scan

Front 10

How much bone must be lost before a change in plain x-ray appearance is evident?

Back 10

30%

Front 11

Does a DEXA scan evaluate cancellous and cortical bone individually?

Back 11

No, together

Front 12

Does a quantitative CT scan evaluate cancellous and cortical bone individually?

Back 12

Yes, can separate

Front 13

What is the downside of quantitative CT?

Back 13

Increased radiation

Front 14

What test is the most accurate for determining bone density?

Back 14

Quantitative CT

Front 15

What test is the most reliable for predicting fracture risk?

Back 15

DEXA scan

Front 16

What are the two general types of osteoporosis?

Back 16

Type I: postmenopausal
Type II: age related (>75 years old)

Front 17

With type I osteoporosis, what type of bone is principally affected?

Back 17

Trabecular bone (cancellous)

Front 18

Give two examples of typical type I fractures?

Back 18

Vertebral body fractures
Distal radius fractures

Front 19

With type II osteoporosis, what type of bone is principally affected?

Back 19

Trabecular and cortical bone

Front 20

Give two examples of typical type II fractures?

Back 20

Hip fracture
Pelvic fracture

Front 21

How do bisphosphonates affect osteoclast microstructure?

Back 21

Disrupt microtubules within the ruffled border

Front 22

How do they disrupt macrostructure?

Back 22

Disrupt protein prenylation

Front 23

What disadvantageous effect do high-dose bisphosphonates have?

Back 23

Disrupt calcium deposition also, not just resorption

Front 24

Over what period of time does the peak bone loss occur?

Back 24

First 16 months after injury

Front 25

After that period of time, how much bone mass remains?

Back 25

Two thirds of the preinjury bone mass

Front 26

What anatomic region is most affected by bone loss?

Back 26

Knee

Front 27

What anatomic region is most spared by bone loss?

Back 27

Skull