Sbm - Orthopedic Pathology (369-70)

Front 1

60-70% of bone is inorganic, composed of this material

Back 1

hydroxyapatite

Front 2

30% of bone is composed of organic material. Of the organic material, 90% is composed of ___________

Back 2

type I collagen

Front 3

the so-called "growth plate" includes these two structures

Back 3

epiphysis, metaphysis

Front 4

achondroplasia results from a mutation in this gene

Back 4

FGF3 (AD)

Front 5

strands of connective tissue that connect periosteum to cortext

Back 5

Sharpey fibers

Front 6

Two types of immature bone: osteoid and woven bone.

What is the main difference between them?

Back 6

Woven - mineralized
Osteoid - unmineralized

Front 7

Two types of immature bone: osteoid and woven bone.

What is the main similarity between them?

Back 7

Formed *much* more rapidly than lamellar (mature) bone

Front 8

Osteoblasts express this protein to activate osteoclasts

Back 8

RANK-ligand

Front 9

Osteoclasts are found in resorption pits called ________

Back 9

Howship's lacunae

Front 10

By what mechanism does the osteoclast resorb inorganic bone?

Back 10

H-ATPase pump

-pumps HCl into the resorption pit
-liberates Ca, Mg, PO4

Front 11

Using what protein does osteoclast degrade organic component of bone?

Back 11

Cathespin K

Front 12

Disorder of abnormal matrix in which there is a defect in synthesis of type I collagen

Back 12

Osteogenesis imperfecta

Front 13

Why do persons with OI have brittle bones?

Back 13

Osteoid doesn't form correctly on abnormal cartilage

(Remember: OI = defect in Type I collagen)

Front 14

A patient with atraumatic fractures is suspicious for having what bone disorder?

Back 14

osteoporosis (postmenopausal and senile subtypes)

Front 15

What is the pathogenesis of POSTMENOPAUSAL osteoporosis?

Back 15

-Estrogen deficiency --> *increased osteoclasts*

-wrist and vertebral fractures
-high turnover osteoporosis

Front 16

What is the pathogenesis of SENILE osteoporosis?

Back 16

-*decrease in osteoblast* production and activity

-hip & vertebral fractures
-low turnover form

Front 17

What are 3 top causes of hyperparathyroidism?

Back 17

1ry: adenoma, chief cell hyperplasia

2ry: chronic renal failure

Front 18

Pathologic findig in hyperparathyroidism in which osteoclasts tunnel down the long axis of a bone

Back 18

Dissecting osteitis

Front 19

Paget's disease of bone

a. primary cell type
b. associated virus?

Back 19

a. multinucleated osteoclasts (--> chaotic, shitty bone)

b. Paramyxovirus

Front 20

Characteristic radiographic finding in Paget's disease?

Back 20

chalk-stick fracture

Front 21

characteristic histology of Paget's disease includes this feature

Back 21

cement lines

= haphazardly arranged mucopolysaccharides

Front 22

Because the stroma is highly vascularized, the first (osteolytic) phase of Paget's dz of bone can lead to this condition

Back 22

high output cardiac failure

Front 23

Disease of too little bone resorption

Back 23

osteopetrosis

Front 24

What is the pathogenesis of osteopetrosis?

Back 24

H+ATPase deficiency --> osteoclast can't acidify resorption pit --> thickened, brittle bone

Front 25

2x hematologic abnormalities in osteopetrosis?

Back 25

Crowding out of marrow -->

-anemia
-extramedullary hematopoiesis

Front 26

Characteristic imaging finding in osteopetrosis?

Back 26

Erlenmeyer flask deformity

Front 27

This cell type can't mature without vitamin D, which is the cause of osteoporosis

Back 27

Chondrocytes

Front 28

Association:

cartilage cap on bony stalk

Back 28

osteochondroma

Front 29

Osteochondroma (3 facts)

Back 29

-cartilage cap on bony stalk
-most common Benign bone tumor in KIDS
-M for metaphysis origin in long bones of extremity

Front 30

Association:

nocturnal pain relieved by aspirin/nsaids

Back 30

osteoid osteoma

(the one bone tumor with distinctive physical sx)

Front 31

Tx of osteoid osteoma

Back 31

remove nidus

Front 32

Cartilaginous lesion within bone that has arc+ring appearance on X ray

Back 32

Enchondroma

Front 33

Multiple enchondromata on one side of the body with no other sx

Back 33

Ollier's disease

Front 34

Multiple enchondromata on one side of body + hemangiomas (soft tissue/viscera)

Back 34

Maffuci's syndrome

Front 35

Tumor of osteoclasts

Back 35

Giant cell tumor

-usu solitary lesions

Front 36

If giant cell tumor is suspected and there are multiple lesions in odd places, consider this diagnostic possibility

Back 36

hyperparathyroidism

Front 37

Association:

Multinucleated (>50) osteoclasts

Back 37

giant cell tumor

Front 38

Neoplastic condition in which [abnormal maturation of abnormal osteoblasts --> formation of abnormla bone]

Back 38

fibrous dysplasia

Front 39

McCune Albright syndrome is associated with this neoplastic condition

Back 39

Fibrous dysplasia

Front 40

Name the disease:

polyostotic fibrous dysplasia with cafe au lait spots and endocrinopathy

Back 40

McCune Albright syndrome

Front 41

Association:

Effect of pre-operative chemo on this tumor determines prognosis

Back 41

Osteosarcoma

Front 42

Two characteristic X ray findings in osteosarcoma

Back 42

-codman's triangle
-sunburst reaction

Front 43

Association:

-codman's triangle
-sunburst reaction

Back 43

Osteosarcoma

Front 44

Association:

dead bone surrounded by cartilage

Back 44

chondrosarcoma

Front 45

Association:

small, round blue cell tumor

Back 45

Ewing's sarcoma

Front 46

Ewing's sarcoma translocation?

Back 46

t (11;22)

Front 47

Mutation associated with osteosarcoma

Back 47

Rb

Front 48

Most common malignant bone tumor of adults and kids

Back 48

osteosarcoma