Msk 4

Question 1

RANKL-RANK interaction does what?

Answer 1

activates NF-KB, thus generation and survival of osteoclasts - bone resorption

Question 2

What cell gives rise to all connective tissue (fat, bone, etc) and osteoblasts?

Answer 2

Mesenchymal/stromal stem cell

Question 2

Softening of bones, failure of mineralization, most often related to lack of vitamin D

Answer 2

Rickets and osteomalacia

Question 4

Later and slower cortical bone loss is more associated with what type of osteoporosis?

Answer 4

senile - decreased osteoblast activity, long bone fractures

Question 5

Osteoporosis is a disease of old age, but it starts at birth

Answer 5

Amen.

Question 6

What substance can inhibit osteoclastic bone resorption?

Answer 6

Bisphosphonates - impairs ruffled border, adherence, and ability to produce necessary protons, & decreases osteoclast development/promotes apoptosis

Question 7

Primary, immature bone

Answer 7

Woven bone

Question 7

Secondary, mature bone

Answer 7

Lamellar bone

Question 7

Occurs in adults with closed epiphyses

Answer 7

Osteomalacia

Question 8

Hypersecretion of PTH due to adenoma formation in parathyroid gland

Answer 8

Primary hyperparathyroidism

Question 9

Microfractures and secondary hemorrhages that lead to an influx of macrophages & ingrowth of repairative fibrous tissue leads to a mass of reactive tissue known as a

Answer 9

brown tumor

Question 10

Regular parallel bands of collagen arranged in sheets, compact & trabecular types

Answer 10

Lamellar (mature) bone

Question 10

What gives rise to osteocytes?

Answer 10

Osteoblasts that have been trapped in solid bone

Question 10

Persistent osteoid seam (light purple- narrow region of newly formed matrix not yet mineralized) along bone in microscope

Answer 10

Osteomalacia

Question 11

Which form of hyperparathyroidism results in compensatory secretion of PTH?

Answer 11

Secondary

Question 12

Skull deformities, rachitic rosary at costochondral junction of ribs, pectus carinatum, pigeon chest, lumbar lordosis, bowing of legs, fractures

Answer 12

Rickets

Question 14

What are the 3 types of primary osteoporosis?

Answer 14

Postmenopausal, senile, idiopathic

Question 15

Skeletal changes of chronic renal disease

Answer 15

delayed matrix mineralization, increased osteoclastic bone resorption, growth retardation, osteoporosis

Question 16

True or false, osteomalacia involves failure of mineralization of growth cartilage

Answer 16

False. Rickets- growth cartilage. Osteomalacia & rickets- osteoid matrix

Question 16

How does vitamin D contribute directly to mineralization?

Answer 16

stimulates osteoblasts to synthesize Ca-binding protein osteocalcin, which is involved in mineralization of epiphyseal caratilage and osteoid matrix

Question 17

randomly arranged collagen fibers in osteoid, produced rapidly when there is a need, evenly remodelled

Answer 17

Woven (immature) bone

Question 19

What cell gives rise to B cells, T cells, leukocytes, and osteoclasts?

Answer 19

Hematopoietic stem cell

Question 20

Excessive kyphosis and excessive lordosis is due to

Answer 20

Vertebral compression fractures in thoracic & lumbar region - osteoporosis 4.15

Question 22

Occurs in children with open epiphyses

Answer 22

Rickets

Question 23

Do dark or light skinned people make more vitamin D?

Answer 23

Light- due to melanin pigmentation & sunlight

Question 24

Osteoclasts boring into the center of a bony trabecula

Answer 24

Dissecting osteitis

Question 26

Trabecular bone loss is more associated with what type of osteoporosis?

Answer 26

postmenopausal - increased osteoclast activity, vertebral compression fractures

Question 27

How much of variation in bone density is genetically determined?

Answer 27

60-80% - genes RANKL, OPG, and RANK

Question 29

When is the peak bone mass during the human life?

Answer 29

ages 25-30

Question 30

True or false, the sun helps provide 90% of vitamin D.

Answer 30

True.

Question 31

Answer 31

Brown tumor

Question 32

Decreased estrogen results in (sepcific)?

Answer 32

Increased IL-1, IL-6 & TNF, leads to increased osteoclasts & RANKL, while OPG decreases

Question 33

Overgrowth and disorganization of epiphyseal cartilage due to inadequate calcification and failure of cartilage cells to mature and disintegrate

Answer 33

rickets

Question 34

Will every person with osteopenia develop osteoporosis?

Answer 34

No. Osteopenia means mineral density is lower than normal, but osteoporosis indicates an actual risk for fractures

Question 35

skeletal manifestation of advanced hyperparathyroidism, subperiosteal bone resorption & brown tumors, more common in primary hyperparathyroidism

Answer 35

osteitis fibrosa cystica (aka osteitis fibrosa or von recklinghausen disease of bone)

Question 36

How do we diagnose osteoporosis?

Answer 36

Dual-energy X-ray Absorptiometry (DEXA) & quantitative computed tomography. NOT plain radiograph.