Osteoporosis Pathophysiology

Question 1

Define osteoporosis

Answer 1

Low bone density and structural deterioration of bone tissue

Question 2

Define T score

Answer 2

Patient’s bone mineral density as the number of SD above or below the mean for a normal young adult

Question 3

Define Z score

Answer 3

compares BMD to a group of matched age, weight, sex and race

Question 4

Osteopenia vs Osteoporosis T scores

Answer 4

Penia: -1 to -2.5
Porosis: <-2.5

Question 5

OP Epidemiology

Answer 5

Women
White and hispanic = highest fragility fracture rate
Rises with age
Hip fractures!!

Question 6

Postmenopausal OP

Answer 6

BMD loss caused by estrogen deficiency affecting primary trabecular bones

Question 7

Age related OP

Answer 7

Bone resoprtion > formation

Reduced quality of new bond

Question 8

Secondary OP

Answer 8

Glucocorticoid caused

Question 9

Define bone remodeling

Answer 9

Once laid down, bone is ubject to a process of breakdown and renewal

Question 10

Bone Remodeling details

Answer 10

Osteoclast secrete acid to dissolve the hydroxyapatite crystals and enzymes that degrade collagen and fibers
Resorption (preblasts to blasts)

Question 11

Osteoblasts secrete what which does what?

Answer 11

OSP decoy receptor and inhibits osteoclast maturation and activity

Question 12

Postmenopausal Patho

Answer 12

Loss caused by increased bone resorption due to estrogen deficiency

Question 13

Estrogen deficiency

Answer 13

release of cytokines –> increase RANKL and decreased OPG –> osteoclasts maturation
Favors calcium excretion

Question 14

Age related bone loss results from

Answer 14

Decreased blast function
Reduced Calcium and Vit D
Reduced sex hormones
Decrease mechanical stimuli

Question 15

Drug induced OP drugs?

Answer 15

Glucocorticoids
Heparin
Thryoid hormones
Anticonvulsants

Question 16

OP RF Non-Modifiable

Answer 16

Advanced age
Gender
Genetics
Race
Low BMD

Question 17

OP RF Modifiable

Answer 17

Low BMD
Smoking
Alcohol
Low calcium and testosterone/estrogen
Min sun expoure
Immobility

Question 18

Define hyphosis

Answer 18

Posterior curvature of the thoracic spine

Question 19

Define Lordosis

Answer 19

Anterior curvature of the lumbar and cervical region of the spine

Question 20

Calcium

Answer 20

Diary products
Caffeine increase calcium excretion
Calcium carboonate is teh salt of choice

Question 21

Vitamin D and Clacitriol

Answer 21

Converted via PTH and estrogen

Calcitriol needs its receptor which is mediated via VDR which is inhibited by glucocorticoids

Question 22

PTH

Answer 22

Peptide hormone that raises plasma calcium and is synthesized by the parathyroid gland
Parathroid gland has calcium-sensing receptors which help regulate PTH

Question 23

What does PTH really do?

Answer 23

Enhance calcium reabsorptions
Stimulate renal production of vitamin d
Increases bone resorption

Question 24

Osteoclasts do not have?

Answer 24

PTH receptors