Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MSK II Midterm > Bone pathology > Flashcards

Bone pathology Flashcards

1
Q

What kinds of bones develop from intramembranous ossification?

A
  • flat bones: formation of bone without a preexisting cartilage matrix
  • the others do endochondral ossification… mostly long bones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

If someone has short thumb and big toe, what gene is messed up?

A

-HOXD13

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

What is cleidocranial dysplasia?

A
  • LOF mutation in RUNX2

- patent fontanelles

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

Achondroplasia

A
  • impaired cartilage proliferation in the growth plate
  • common cause of dwarfism
  • short extremities
  • intramembranous bone not affected
  • mental function, life span, and fertility are not affected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

mutation in achondroplasia

A
  • activating mutation in FGFR3
  • overexpression inhibits growth
  • most mutations are sporadic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Thanatophoric dysplasia

A
  • mot sommon lethal form of dwarfism
  • bell shaped abdomen
  • shorened limbs, frontal bossing, macrocephaly…
  • die at birth or soon after
  • also GOF FGFR3 mutation, but different from achondroplasia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Osteogenesis Imperfecta

A
  • congenital defect of bone fomration resulting in structurally weak bone
  • Auto dominant defect in Collagen type 1 synth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Clinical features of OI?

A
  • multiple fractures of bone
  • blue sclera: thinning of scleral collagen reveals underlying choroidal veins
  • hearing loss: bones in the middle ear easily fracture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Gene defect in OI

A

-COL1A1 or 2

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

Which subtype of OI is especially lethal?

A
  • type 2

- that is the only predominantly auto recessive one, the other 3 are dominant

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

Osteopetrosis

A
  • inherited defect of bone resorption resulting in abnormally thick, heavy bone that fractures easily
  • due to poor osteoclast function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

mutation of what enzyme is in osteopetrosis?

A
  • carbonic anhydrase 2 (makes carbonic acid from H20 and CO2)
  • loss of acidic environment needed for bone resorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

clinical features of osteopetrosis

A
  • bone fractures
  • pancytopenia… bony replacement of the marrow (myelophthisic process)
  • vision and hearing impairment.. impinges CN’s
  • renal tubular acidosis: we can’t reabsorbe bicarb now… metabolic acidosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Tx for osteopetrosis

A
  • bone marrow transplant!

- osteoclasts are derived from monocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

another name for osteopetrosis

A

-alber-schonberg disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What big morphology buzzword is for osteopetrosis

A

-erlenmeyer flask

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

Genetic defect for osteopetrosis

A
  • auto dominant: LRP5… hearing loss

- Infantile form: RANKL (auto recessive)

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

Mucopolysaccharaidoses

A
  • they accumulate inside chondrocytes… apoptosis

- abnormalities in hyaline cartilage

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

difference between osteopenia nad osteoporosis?

A
  • osteoporosis is bone mass 2.5 sd’s lower than mean peak bone mass
  • oseopenia is 1-2.5
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

most common forms of osteoporosis?

A

-senile and postmenopausal forms

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

What is osteoporosis

A
  • reduction in trabecular bone mass
  • results in porous bone with an increased risk for fracture
  • risk of oseoporosis is based on peak bone mass and rate of bone loss that follows after
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

clinical features of osteoporosis

A
  • bone pain and fractures in weight-bearing areas like the vertebrae, hip, and distal radius
  • bone density is measured using a DEXA scan
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How are the serum calcium, phosphate, pth, and alk phos levels in osteoporosis?

A
  • NORMAL

- this helps to exclude osteomalacia which is nice because it’s like the same presentation

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

Tx of osteoporosis

A
  • exercise, vti D, and Ca2+
  • Bisphosphonates: induce apoptosis of oseoclasts
  • Estrogen replacement therapy is debated
  • glucocorticoids are contraindicated (worsen osteoporosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

gene defect for osteoporosis-pseudoglioma syndrome?

A
  • LRP5

- infant onset loss of vision, skeletal fragility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

gene defect for osteopetrosis with renal tubular acidosis

A

-CA2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

gene defect for osteopetrosis, late onset type 2?

A
  • CLCN7

- chloride channel, increased bone density, fragility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the top genetic factors for osteoporosis?

A

-RANKL, OPG, and RANK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

hallmoar of osteoporosis?

A

-histologically normal bone that is decreased in quantity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

where in the body will we see the effects of postmenopausal osteoporosis the most?

A

-vertebral bodies or bones that have a lot of surface area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

is measurement of blood levels of Ca2+, Phosphorous, and alk phos diagnostic for osteoporosis?

A
  • no!

- remember those labs are normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Paget Disease (osteitis deformans)

A

-imbalance betwen osteoclast and osteoblast function
-late adulthood… old ppl
-localized process involve one or more bones: DOES NOT INVOLVE THE ENTIRE SKELETON
-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What gene involvement is shared between OI and dermatofibrosarcoma protuberans?

A
  • COL1A1

- remember in the derm one, it’s a translocation between COL1A1 and PDGFB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the 3 stages of paget disease of bone?

A
  • osteoclastic
  • mixed osteoblastic-clastic
  • osteoblastic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the end result of paget disease

A
  • thick, sclerotic bone that fractures easily

- biopsy reaveal a MOSAIC pattern of lamellar bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Clinical features of paget diseas

A
  • bone pain: microfractures
  • increasing hat size: skull is commonly affected
  • hearing loss: impinging CN’s
  • lion-like facies: involvement of craniofacial bones
  • isolated elevated alk phos
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the most common cause of isolated elevated alk phos in patients >40 y/o?

A

-Paget disease of bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Tx of paget disease

A
  • calcitonin: inhibits osteoclast function

- disphosphonates: induces apoptosis of osteoclasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Complications of Paget disease

A
  • high-output cardiac failure: due to formation of AV shunts in bone
  • osteosarcoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

gene mutation for paget disease

A
  • SQSTM1 gene

- increased activity of NFKB….increases osteoclast activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

how will the osteoclasts look in paget disease?

A
  • abnormally large

- more than normal 10 to 12 nuclei, sometime 100!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What region of the body is involved with paget disease?

A
  • axial skeleton or prox femur

- can have leontiasis ossea (lion face)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How will the femurs look in pagets disease?

A

-weight bearing causes anterior bowing of the femurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How will the skin look and feel in pagets?

A

-warms overlying skin bc hypervascularity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

labs for someone with pagets?

A
  • elevated serum alk phos

- normal serum Ca2+ and phosphorous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Ricketts

A
  • defective mineralization of osteoid
  • low vit D… leads to low Ca and P
  • this one is with children
  • pigeon breast deformity
  • fronal bossing
  • rachitic rosary
  • bowing of the legs
47
Q

what is the common theme is ricketts problems?

A

-deposition of osteoid in places

48
Q

Osteomalacia

A
  • low Vit d in Adults

- bad mineralization… weak bone… increased risk for fracture

49
Q

lab findings for osteomalacia

A
  • low Ca2
  • low P
  • high PTH
  • high alk phos: happens when there is osteoblasts activated
50
Q

If we have hyperparathyroidism, what three skeletal abnormalities will be there?

A
  • osteoporosis: more severe in phalanges, vertebrae, and proximal femur
  • brown tumors: vascularity, hemorrhage, and hemosiderin
  • osteitis fibrosa cystica
51
Q

What does BMP-7 induce?

A
  • osteoblast differentiation

- secreted by kidneys

52
Q

FGF-23

A
  • made by osteocytes

- acts on kidney to regulate phosphate homeostasis and vit D production (dependent on Klotho)

53
Q

simple fracture

A

-skin is intact

54
Q

compund

A

-bone communicates with the skin

55
Q

comminuted

A

-bone is fragmented

56
Q

displaced

A

-ends of the bone at the fracture site are not aligned

57
Q

stress

A

-slowly developing fracture that follows a period of increased physical activity in which the bone is subjected to repetitive loads

58
Q

greenstick fracture

A

-extending only partially through the bone, common in infants when bones are soft

59
Q

pathologic fracture

A

-involves bone weakened by an underlying disease process, such as a tumor

60
Q

is the cortex normally affected by avascular necrosis?

A
  • no

- the trabecular bone and marrow are though

61
Q

Osteomyelitis

A
  • infection of marrow and bone
  • usually in children
  • bacterial usually, arises via hematogenous spread
  • transient bacteremia seeds metaphysis (children)
  • open wound bacteremia seeds epiphysis (adults)
62
Q

causes of osteomyelitis

A
  • Staph aureus… most common
  • N gonorrhoea: sex ppl
  • salmonella: sickle cell
  • pseudomonas: Diabetic or IV drug abusers
  • pasteurella: dog or cat bite
  • Mycobacterium tuberculosis: usually involves vertebrae (pott disease)
63
Q

clinical features of osteomyelitis

A
  • bone pain with systemic signs of infection
  • lytic focus surrounded by sclerosis of bone on x ray, lytic focus is called sequestrum, and sclerosis is called involucrum
64
Q

brodie abscess

A

-small IO abscess that frequently involves the cortex and is walled off by reactive bone

65
Q

Sclerosing osteomyelitis of Garre

A
  • jaw

- extensive new bone formation that obscures much of the underlying osseous structure

66
Q

How is the diagnosis of osteomyelitis made?

A

-by blood culture

67
Q

What will skeletal syphyllis look like?

A
  • saber shins
  • see it on silver histochemical stains
  • gummas
68
Q

Avascular septic necrosis

A
  • ischemic necrosis of bone and marrow
  • causes include trauma or fracture, steroids, sickle cell anemia, and caisson disease
  • osteoarthritis and fracture are major complications`
69
Q

Osteoid osteoma

A

-benign tumor of osteoblasts surrounded by a rim of reactive bone
-young adults
-cortex of long bones
-

70
Q

presentation of osteoid osteoma

A
  • bone pain that RESOLVES WITH ASPIRIN
  • imagin: bony mass with a radiolucent core
  • appendicular skeleton
71
Q

How is osteoid osteoma different from osteoblastoma?

A

-osteoblastoma is similar to this but it’s larger (>2cm), arises in vertebra, and presents as bone pain that DOES NOT RESPOND TO ASPIRIN

72
Q

What does the osteoid osteoma and osteoblastoma look like

A

-round to oval masses of hemorrhagic gritty tan tissue

73
Q

Osteosarcoma

A
  • Malignant proliferation of osteoblasts
  • teens
  • pathologic fracture or bone pain with swelling
74
Q

Imaging for osteosarcoma

A
  • sunburst

- codman triangle

75
Q

risk factors for osteosarcoma

A

-familial retinoblastoma, paget disease, and radiation exposure

76
Q

Where does osteosarcoma arise?

A

-in the metaphysis of long bones, usually the distal femure or proximal tibia (the knee!)

77
Q

biopsy for osteosarcoma

A

-pleomorphic cells that produce osteoid

78
Q

What genes will be mutated in osteosarcoma?

A
  • RB: negative regulator of cell cycle
  • TP53 (li fraumeni)
  • INK4a (inactivated)
  • MDM2 and CDK3: inhibit p53 and RB function
79
Q

what is diagnositc for osteosarcoma?

A

-formation of bone by tumor cells

80
Q

What is an osteosarcoma called when malignant cartilage is abundant?

A

-chondroblastic osteosarcoma

81
Q

Where does osteosarcoma like to spread to?

A

-the lungs! hematogenously

82
Q

Morphology of osteosarcomas?

A
  • bulky tumors that are gritty, gray-white

- remember that osteomas were gritty tan colored

83
Q

outcome for osteosarcoma patients with metastases?

A

-poor

84
Q

Osteochondroma

A
  • tumor of bone with an overlying cartilage cap; most common benign tumor of bone
  • arises from a lateral projection of the growth plate (metaphysis); bone is continuous with the marrow space
  • overlying cartilage can transform (rarely) to chondrosarcoma
85
Q

pathogenesis of osteochondroma

A
  • reduced expressiong of EXT1 or EXT2

- these genes encode enzymes that synthesize heparan sulfate glycosaminoglycans

86
Q

What is another name for osteochondroma?

A

-exostosis

87
Q

When do osteochondromas stop growing?

A

-at the time of growth plate closure… makes sense because it comes from the metaphysis

88
Q

Chondroma

A
  • benign tumor of cartilage

- usually arises in the medulla of small bones of the hands and feet

89
Q

What 2 syndromes have multiple enchondromas?

A
  • Maffucci syndrome and Ollier disease

- Maffucci also has spindle cell hemangiomas

90
Q

pathogenesis of chondromas

A
  • heterozygous mutations in the IDH1 and IDH2 genes
  • encode 2 isoforms of isocitrate dehydrogenase… leads to synth of 2-hydroxyglutarate
  • that is an oncometabolite… interferes with regulation of DNA methylation
91
Q

If someone has maffucci syndrome, what else are they at risk for?

A

-other types of malignancies like ovarian carcinomas and brain gliomas

92
Q

Chondrosarcoma

A
  • malignant cartilage-forming tumor

- arises in medulla of the pelvis or central skeleton

93
Q

What is special about the clear cell variant of chondrosarcoma?

A

-it originates in the epiphyses of long tubular bones

94
Q

What is a dedifferentiated chondrosarcoma

A

-low grade chondrosarcoma with a second, high grade component that does not produce cartilage

95
Q

presentation of chondrosarcomas

A

-painful, progressively enlarging masses

96
Q

where do chondrosarcomas spread to?

A

-hematogenously to the lungs

97
Q

Ewing sarcoma

A
  • malignant proliferation of poorly-differentiated cells derived from neuroectoderm
  • arises in the diaphysis of long bones; usually in male children
  • onion skin appearance on x ray
98
Q

what will biopsy show us for ewing sarcoma?

A
  • small, round blue cells that resemble lymphocytes

- can be confused with lymphoma or chronic osteomyelitis

99
Q

What is the characteristic tranlocation for ewing sarcoma?

A
  • 11,22

- EWS (22) and FLI1 (11) genes

100
Q

How does ewing sarcoma often present?

A
  • with mets

- responsive to chemo

101
Q

what gives us a clue that ewing sarcoma has a greater degree of neuroectodermal differentiation?

A

-homer-wright rossettes

102
Q

What is an important prognostic finding for ewing sarcomas?

A

-the amount of chemo induced necrosis

103
Q

Giant cell tumor

A
  • comprised of multinucleated giant cells and stomal cells
  • occurs in young adults
  • arises in epiphysis of long bones, usually the distal femur or prox tibia (knee)
  • soap bubble appearance on x ray
  • locally aggressive, may recur
104
Q

what is a synonym for giant cell tumor?

A
  • osteoclastoma

- often destroy the overlying cortex

105
Q

morphology for giant cell tumor

A
  • sheets of uniform oval mononuclear cells and numerous osteoclast-type giant cells
  • the tumor cells do not synthesize bone or cartilage, but reactive bone may be present at the periphery
106
Q

anuerysmal bone cyst (ABC)

A
  • tumor characterized by multiloculated blood-filled cystic spaces
  • eccentric, expansile lesion with well-defined margins
107
Q

pathogenesis of ABC

A
  • rearrangements of chormosome 17p13
  • results in fusion of coding region of USP6 to promoters of genes that are highly expressed in osteoblasts… leads to USP6 overexpression
108
Q

What is USP67

A
  • encodes ubiquitin specific protease… regulates activity NFKB
  • so a lot of NFKB floating around
  • that upregulates metalloproteases that lead to cystic resorption of bone
109
Q

morphology of ABC

A

-multiple blood filled cystic spaces separated by thing, tan-white septa

110
Q

What is fibrous dysplasia?

A

-all components of normal bone are present, but they do not differentiate into mature structures

111
Q

What is Mazabraud syndrome

A
  • fibrous dysplasia

- soft tissue myxomas

112
Q

McCune -Albright syndrome

A

-polyostotic disease with cafe-au-lait skin pigmentations and endocrine abnormalities, especially precocious puberty

113
Q

what is the mutation for fibrous dysplasia?

A
  • GOF in GNAS1
  • also mutated in pituitary adenomas
  • make a constitutively active Gs ptn

MSK II Midterm (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions