MSK pt 2 Flashcards

1
Q

What animals are affected by viral bone lesions?

A

young growing animals with open physes

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

what is the pathogenesis of viral bone lesions?

A
  1. viruses damage osteoclasts
  2. abnormal osteoclast activity
  3. metaphyseal trabeculae are not remodelled = metaphyseal osteosclerosis/growth retardation lattices
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

which family of viruses commonly cause viral bone lesions?

A

pestiviruses

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

what is osteosclerosis?

A

disorder characterized by abnormal hardening of bone and elevation of bone density

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

What is the lesion in this bone? likely cause?

A

metaphyseal osteosclerosis
pestivirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define these terms:
1. osteitis
2. osteomyelitis

A
  1. inflammation of the bone
  2. inflammation of the bone and medullar cavity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

osteomyelitis is most often associated with ___ or ____ infections.

A

bacterial, fungal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the 3 sources of bone infections?

A
  1. direct introduction (penetrating wound/open fx)
  2. extension from ST (cellulitis, periodontitis, otitis media)
  3. hematogenous spread
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is embolic osteomyelitis?

A

the blood supply to the physis includes capillaries that make sharp bends, which are prone to turbulence, thrombosis, and slow flow. This means that bacteria that get into the blood supply can lodge in these bends and proliferate, causing osteomyelitis (suppurative)

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

What is the pathogenesis of embolic osteomyelitis?

A
  1. source of bacteria
  2. bacteria spread hematogenously
  3. bacteria lodge in physeal capillaries
  4. bacteria proliferate and spread locally
  5. suppurative osteomyelitis develops
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In embolic osteomyelitis, bacteria lodge in the capillaries and form _____.

A

microabsecces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the lesion in this bone?

A

embolic osteomyelitis/suppurative osteomyelitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

embolic osteomyelitis affects which animals most?

A

neonatal calves, lambs, foals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the common bacterial species that cause embolic osteomyelitis?

A

Trueperella pyogenes, Staphylococcus sp, Escherichia coli, Salmonella enterica

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

What is the lesion in this bone?

A

Suppurative osteomyelitis

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

What is the etiology of Lumpy Jaw?

A

Actinomyces bovis

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

what is the pathogenesis of lumpy jaw?

A
  1. damage to oral mucosa provides port of entry (ex. trauma from foreign bodies, coarse feed, periodontitis/dental disease/tooth eruptions)
  2. ST infection
  3. extension into mandible
  4. pyogranulomatous osteomyelitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the gross lesions of lumpy jaw?

A
  • necrotic tracts of pyogranulomatous inflammation, may drain as thick pus to the skin surface (fistula)
  • concurrent periosteal bone proliferation and lysis
  • honeycomb appearance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

This is a mandible (idk what species). What is the lesion?

A

lumpy jaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What caused this lesion? What is the pathology called?

A

Actinomyces bovis

Lumpy jaw

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

What is the lesion and pathology?

A

Pyogranulomatous osteomyelitis

Lumpy jaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what types of osteomyelitis are seen with fungal osteomyelitis?

A

pyogranulomatous to granulomatous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the most common differential diagnosis when it comes to fungal osteomyelitis?

A

bone neoplasia

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

fungal osteomyelitis is ____ (more/less/the same) common than bacterial myelitis. The risk is ____ and ____ dependent.

A

less common

geographically, species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the clinical signs of fungal osteomyelitis?

A

fever, weight loss, bone pain

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

What is this picture showing?

A

fungal osteomyelitis (pyogranulomatous/granulomatous osteomyelitis)

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

what is the pathogenesis of fungal osteomyelitis caused by Blastomyces?

A
  1. inhalation
  2. hematogenous spread and apparent predilection for lungs (fungal pneumonia) and less often appendicular bones
  3. granulomatous osteomyelitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the three species of fungus that commonly cause fungal osteomyelitis, and which species are affected by each?

A
  1. Blastomyces dermatitidis – dogs
  2. Coccidioides spp – horses, dogs, cats, llamas
  3. Cryptococcus spp – cats! (esp.), dogs, horses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what are the common gross lesions with fungal osteomyelitis?

A

periosteal new bone thickens bone contour

loss of cortical bone (lysis)

suppurative to pyogranulomatous material

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

what is osteonecrosis and what are the causes?

A

bone necrosis

infection (esp!), trauma (fx, neoplasia, frostbite)

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

what is the pathogenesis of osteonecrosis?

A

bone lesion that causes damage to blood supply, leading to ischemia and infarction

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

You have a bone with osteonecrosis. What are the next steps that the bone takes? what does the outcome depend on?

A

bone tries to remove necrotic tissue by osteoclasts
if it can’t, then a sequestrum is formed

outcome depends on blood supply, size, and proximity to viable tissue

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

what is a sequestrum? what is a bone sequestrum specifically?

A

piece of necrotic tissue that the body cannot absorb

fragment of necrotic bone that are isolated from blood supply (body can’t absorb)

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

what is the arrow pointing to? if this lesion isn’t dealt with, what will occur?

A

area of necrosis in bone

sequestrum will form if necrosic tissue isn’t removed by osteoclasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

bone sequestra are almost always associated with ____!

A

inflammation

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

what are the causes of bone sequestra?

A

comminuted fxs creating bone fragments, osteomyelitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

why are bone sequestra bad?

A

they persist long-term and can interfere with healing –> non-union fx

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

What is the arrow pointing to?

A

bone sequestrum

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

what age/species of animal does metaphyseal osteopathy affect?

A

young (<6 mo) large and giant breed dogs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Describe the lesions that come with metaphyseal osteopathy?

A

initially: bilaterally symmetrical suppurative and fibrinous osteomyelitis of metaphysis of multiple long bones, separation (fx) of metaphysis due to inflammation/necrosis

has a “double growth plate” appearance (double radiolucency parallel to physis)

chronically: periosteal new bone

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

How do you treat metaphyseal osteopathy? what is the cause?

A

spontaneously resolve

unknown cause

42
Q

You see this lesion in a 4 month old Bernese Mountain Dog. What is it?

A

Metaphyseal osteopathy

43
Q

What is aseptic necrosis?

A

osteonecrosis that is not associated with infection

44
Q

What is the other name for aseptic necrosis of the femoral head?

A

Legg-Calvé-Perthes Disease

45
Q

aseptic necrosis of the femoral head:
1. affects who?
2. pathogenesis?

A
  1. mini dog breeds
  2. femoral head infarction –> necrotic bone resorbed by osteoclasts –> articular cartilage collapses
46
Q

describe the lesions associated with aseptic necrosis, specifically of the femoral head

A

articular surface of the femoral head is irregular/bumpy because the subchondral bone has undergone osteonecrosis

47
Q

This is the femoral head of a miniature poodle. What do you think is going on?

A

Aseptic necrosis of the femoral head

48
Q

Hypertrophic osteopathy:
1. AKA?
2. who is affected?
3. pathogenesis?

A
  1. hypertrophic pulmonary osteopathy
  2. dogs mainly, rarely horses and other spp.
  3. unknown
49
Q

Describe the lesions of hypertrophic osteopathy.

A

progressive periosteal new bone formation affecting distal limbs

** typically associated with concurrent intrathoracic disease (pneumonia, lung tumors)

50
Q

How do you treat hypertrophic osteopathy?

A

it regresses if the primary lesion (in the lung) is resolved

51
Q

These bones are from a dog with a lung tumor. what is the lesion?

A

hypertrophic osteopathy

52
Q

What is the synonym for osteochondromas?

A

multiple cartilaginous exostoses

53
Q

describe the lesions of osteochondromas?

A

mass of trabecular bone and cartilage arising from metaphyseal areas of multiple bones

54
Q

what is the progression of osteochondroma

A

appear at a young age and increase until growth stops at skeletal maturity

55
Q

This is a section of a metaphysis from a long bone. Lesions like this appear on multiple bones. what is the pathology?

A

osteochondroma

56
Q

what are the most common and clinically important primary bone neoplasias?

A
  1. osteosarcoma
  2. chondrosarcoma
57
Q

with primary bone neoplasias, diagnosis often requires _____. Clinical ____ and _____ appearance are essential for accurate diagnosis.

A

biopsy
history
radiographic

58
Q

osteosarcomas are ____ growing (slow/fast), _____, (aggressive/non-aggressive), and ______ (benign/malignant)

A

fast growing
aggressive
malignant

59
Q

what exactly is an osteosarcoma? what is a common ddx for this lesion?

A

malignant osteoblasts produce bone and destroy existing bone
ddx: osteomyelitis

60
Q

how does osteosarcoma progress?

A

local invasion and early pulmonary metastasis

61
Q

what are the predilection sites for osteosarcomas?

A

distal radius/ulna, proximal humerus, distal femur, distal/proximal tibia

basically “away from the elbow, towards the knee”

62
Q

with osteosarcoma, what part of the bone is NOT affected?

A

joint spaces

63
Q

osteosarcomas common and rare in what species?

A

common in dogs/cats, rare in other spp

64
Q

This is a bone from a dog. The joint space near the lesion is totally fine. What is your primary differential?

A

osteosarcoma

65
Q

Fill in the table telling you how to differentiate osteosarcomas from osteomyelitis.

A
66
Q

what is a chondrosarcoma?

A

tumor of malignant chondrocytes that product cartilage (not bone!)

67
Q

what is the behaviour of a chondrosarcoma?

A

slow growing, malignant, localized bone destruction

68
Q

where do chondrosarcomas arise from?

A

flat bones

69
Q

in terms of secondary bone neoplasia, which is more common, carcinomas or sarcomas? of the kind that’s more common, what tumor types frequently metastasize into bones?

A

carcinomas&raquo_space;» sarcomas

carcinomas of mammary gland, lung, prostate

70
Q

true or false. Secondary bone neoplasia is overdiagnosed in animals.

A

false. it is probably under diagnosed. animals euthanized before progression, 60% of humans have skeletal metastasis

71
Q

what is the most common location to find secondary bone neoplasia?

A

ribs, vertebrae, proximal long bones

72
Q

Lung-Digit Syndrome:
1. affects who?
2. pathogenesis?
3. why is this significant?

A
  1. cats
  2. pulmonary carcinoma metastasizes to digits –> localized proliferation and spread –> destroys nail bed –> slough claw
  3. you may detect the digit lesion before the lung neoplasia
73
Q

You see this lesion on a cat. What should you look for next? What is this most likely?

A

look at the lungs for neoplasia

this is probably lung-digit syndrome

74
Q

Lead toxicity leads to what lesion in bones?

A

lead line – band of sclerosis within the metaphysis of developing bones – visible radiographically

75
Q

describe the pathogenesis of lead toxicity

A

lead is toxic to osteoclasts –> impaired remodelling –> metaphyseal osteosclerosis

76
Q

You see this lesion during necropsy. what should be on the top of your ddx list?

A

lead toxicity

77
Q

What is chrondrodysplasia?

A

hereditary disorders of bone growth due to abnormal growth cartilage

78
Q

Disproportionate dwarfism is a kind of _____. what is it? which species were highlighted?

A

chondrodysplasia
short-legged with normal-sized heads

all bones undergoing endochondral ossification will be affected

can affect any species, but the breeds are basset hounds, dachshund, pekingese

79
Q

What is osteopetrosis? What is the difference between this and osteosclerosis?

A

osteopetrosis = increased bone density with no medullary cavity

osteosclerosis = increased bone density with medullary cavity

80
Q

what is the cause of osteopetrosis?

A

defective osteoclasts fail to resorb bone

81
Q

osteopetrosis is heritable in which breeds?

A

Angus cattle
Peruvian Paso horses

82
Q

Can osteopetrosis be infectious?

A

yes!
ex. BVD in cattle

83
Q

This is a long bone from a cattle. What is the lesion?

A

osteopetrosis

84
Q

Osteogenesis imperfecta:
1. what is it?
2. pathogenesis?
3. common lesions?

A
  1. genetic disease: abnormal type 1 collagen
  2. reduced trabecular bone –> fxs, joint laxity, and abnormal dentin
  3. blue sclera, pink teeth due to abnormal dentin
85
Q

Tell me the differences between these 3 terms: syndactyly, polydactyly, polymelia

A

syndactyly: partial or complete fusion of digits/phalanges
polydactyly: an increase in the number of digits
polymelia: increase in the number of limbs

86
Q

Tell me which species each of these are common in:
1. syndacyly
2. polydactyly

A
  1. cattle
  2. dogs, cats, horses, cattle
87
Q

What is the lesion? (bird feet)

A

polymelia

88
Q

what is going on?!

A

syndactyly

89
Q

what is going on?

A

polydactyl cutie pie

90
Q

what is brachygnathia inferior?

A

shortening of the mandible (overbite)

91
Q

what is brachygnathia superior?

A

shortening of the maxillae (underbite)

think of brachycephalics

92
Q

what is the lesion?

A

brachygnathia inferior

93
Q

what is this lesion?

A

brachygnathia superior

94
Q

What is lordosis? what is the common name for this in horses?

A

abnormal ventral curvature of the spinal column

swayback

95
Q

What is the lesion?

A

lordosis

96
Q

what is kyphosis? what is the common name of this in horses?

A

abnormal dorsal curvature of the spinal column

roach backs

97
Q

what is the lesion?

A

kyphosis

98
Q

what is scoliosis?

A

abnormal lateral deviation of the spinal column

99
Q

what is the lesion?

A

scoliosis

100
Q

what is spina bifida? where are the most common locations for this? is this usually a lone defect?

A

defective closure of the dorsal vertebral lamina in the vertebral column

most common in lumbar and sacral lesions

no, this is often associated with other defects

101
Q

what is the lesion?

A

spina bifida