Brainscape's Knowledge GenomeTM

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


See full index

VETM 425 > MSK 4 > Flashcards

MSK 4 Flashcards

1
Q

what is the cell type that is key to muscle regeneration?

A

satellite cells, they are able to divide, fuse, and can form mature myofibers

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

if there is muscle damage, what are 3 general clinical findings you might see?

A
  1. increased creatinine kinase (CK)
  2. increased AST
  3. myoglobinuria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are 3 causes of pale muscles?

A
  • necrosis
  • mineral
  • replacement by fat or collagen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are two species that can cause parasitic muscle cysts?

A
  • trichinella spiralis
  • sarcocystis sp
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

name 4 reasons why a muscle would appear dark red

A
  • hemorrhage
  • necrosis
  • inflammation
  • myoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

name two reasons why a muscle might have a green appearance

A
  • autolysis/putrefaction
  • eosinophilic inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what do you see nd how does this help you figure out what it is?

A

green discoloration due to eosinophils (bovine eosinophilic myositis)

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

define the following:
- myopathy
- myositis
- myonecrosis
- cachexia
- polymyositis

A
  • muscle disease
  • muscle inflammation
  • muscle necrosis
  • generalized muscle atrophy caused by disease or malnutrition
  • inflammation of multiple muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how does muscle necrosis appear acutely and chronically?

A

acutely: red
chronic: white chalkly due to progression of mineralization caused by increased intracellular calcium

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

regernation of muscle requires what two things? what happes if you don’t have these two things?

A
  • an in tact basal lamina
  • viable satellite cells

if either of these are damaged, you’ll get healing by fibrosis

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

define muscle atrophy

A

decreased muscle volume, usually reversible if cause is corrected

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

list 3 physiological causes of muscle atrophy

A
  1. disuse (asymmetrical and localized)
  2. cachexia (symmetrical and generalized)
  3. senility (symmetrical and generalized)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how does cancer cause cachexia?

A

catabolic cytokines like tissue necrosis factor

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

name 3 endocrine causes of muscle atrophy

A
  • hypothyroidism (dogs_
  • hypercortisolism (dogs)
  • pituitary dysfunction/tumors (horses)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

why does denervation cause muscle atrophy?

A

muscle fibers require growth factors from nerves for maintenance and loss of nerve supply leads to rapid atrophy

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

this is the skull of a dog. what is happening here?

A

muscle atrophy due to denervation (tumor/disease in trigeminal nerve)

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

laryngeal hemiplasia is an example of _____. explain the pathogenesis

A

denervation atrophy

left recurrent laryngeal nerve is longer and prone to nerve degernation–>denervation of the left circoarytenoideus muscle–>laryngeal paralysis–>loud breathing and possibly aspiration penumonia

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

what is this?

A

laryngeal hemiplasia due to denervation (can see atrophy of left circoaretynoideus muscle)

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

in degenerative muscle diseases, is there inflammation?

A

yes, but inflammation is not the cause of the damage. damage is done first, then inflammatory reaction starts to heal the damage done

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

since muscles have lots of blood supply, how does infarction happen and give one example

A

infarction requires occlusion of large blood vessels or severe intramuscular vascular damage to occur

example is feline aortic thromboembolism where blood supply to the hind legs is blocked and causes paralysis

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

in regards to cell types in the muscles, which are most susceptible to oxygen and which are not? what does this mean for healing?

A

myofibers most susceptible to hypoxia, then satellite cells, then fibroblasts. this means that regernative ability depends on the time in the hypoxic state. If the hypoxia is prolonged, the satellite cells will be damaged and all that’s left is the fibroblasts so healing will occur via fibrosis/scar tissue

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

explain what compartmental syndrome is and provide an example

A

there is muscle damage of some sort leading to inflammation and swelling which increases intramuscular pressure (because the overlying fascia cannot expand), and this leads to ischemic necrosis

ex: recumbency in LA: ischemic necrosis of muscles under pressure when “down” for too long

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

prolonged recumbency in large animals causes what 3 things?

A
  • pressure on the muscle arterial supply
  • compartmental syndrome (inflammation and pressure in muscles)
  • reperfusion injury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is white muscle disease? what are the gross lesions?

A

nutritional deficinecy in Vitamin E/Selenium, which are antioxidants, so without them there are increased free radicals in the skeletal and cardiac muscles

gross lesions: muscles are pale pink to white (degeneration and mineralization), lesions ofen obvious in muscles with high workload like the tongue, heart, limbs, etc

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

horses are susceptible to ionophore toxicity. what does it do to them (pathogenesis) and what will it look like? give an example of an ionophore

A

toxic levels of inophores disrupt ion equilibrium leading to calcium overload–>this leads to skeletal and cardiac muscle necrosis which leads to death

it will cause the muscles to be quite pale from the necrosis, may look like streaks. BUT if acute enough there will be no lesions, just death quickly!

ex: monensin

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

give an example of one toxic plant that can cause a toxic myopathy

A

gossypol in cottonseed

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

explain a brief pathogenesis of capture myopathy

A

the capture and restraint of wildlife leads to struggling and lots of stress for the animal. this leads to massive myonecrosis and death

28
Q

what is exertional rhabdomyolysis?
describe the clinical signs, gross findings, and predisposing factors for the disease

A
  • essentially it is skeletal muscle lysis, mainly in horses (sometimes dogs)
  • clinical signs: stiff gait, swelling, sweating
  • grossly: red swollen muscles and myoglobinuria
  • predisposing: selenium/vit E def, EPSSM
29
Q

name some examples of traumatic myopathies

A

lacerations, surgical incisions, tearing, etc

30
Q

what is myositis?

A

inflammation of the muscle, and this inflammation is then the cause of muscle damage

31
Q

describe a general pathogenesis of bacterial myositis and give examples of common eitologies for this disease in different species

A

usually a result of an inoculation wound–>introduction of bacteria to the area–>suppurative inflammation and necrosis–>abscess formation and extension along fascial planes when severe

strep zooepidemicus in horses
trueperella pyogenes in cattle and sheep
corynebacterium psuedotuberculosis in sheep and goats

32
Q

this is an example of what

A

bacterial myositis

33
Q

this is an example of

A

bacterial myositis (can see the yellow/green fibrinopurulent material in muscle and along fascial planes)

34
Q

how do clostridial species cause myositis? what are some gross lesions of clostridial myositis?

A

they produce toxins that cause hemorrhagic muscle necrosis that can often progress to fatal tomexia/septicemia

gross: localized affected muscles are hemorrhagic, swollen, edematous, with suppurative inflammation and gas pockets

35
Q

breifly explain the clostridial myositis general pathogenesis

A

muscle damage leads to anaerobic conditions, which allows spores to germinate and the bacteria can produce toxins. These toxins damage blood vessels and muscles leading to hemorrhage and necrosis, leading to myositis and even more anaerobic tissue for bacterial proliferation (vicous positive feedback cycle)

36
Q

this cow was found acutely dead. what is your differential?

A

blackleg/clostridial myositis

37
Q

explain the specific pathogenesis of clostridial myositis in cattle via clostridium chauvoei

A

the cow ingests the spores–>spores cross the intestinal mucosa–>hematogenous spread to the muscles–>muscle trauma leads to anaerobic conditions allowing bacteria to proliferate–>bacteria produce toxins and cause vascular damage–>hemorrhage, necrosis, and edema–>myositis

38
Q

grossly how does a cow look with clostridial myositis caused by clostridium chauvoei?

A

skeletal muscles will be hemorrhagic, edematous, and there will be crepitus, and myonecrosis

39
Q

how do horses get clostridial myositis, what is the cause, and what is the unique namefor this disease in horses?

A

name: malignant edema or gas gangrene
cause: clostridium septicum

usually a penetrating wound is how it starts–>creates localized muscle damage and introduction of spores–> these spores germinate in anaerobic conditions–>bacteria proliferate and produce toxins–>vascular injury–>hemorrhage, necrosis, edema–>myositis

40
Q

what are they doing to this horse? what are they trying to treat?

A

this horse likely has clostridial myositis, and the small incisions allow oxygen into the site of infection to try and eliminate proliferation of anaerobic bacteria

41
Q

what two bacteria species are associated with pyogranulomatous and fibrosing glossitis?

A

actinobacillus lignerisii (wooden tongue), actinomyces bovis (lumpy jaw, less common)

42
Q

what is this an example of?

A

pyogranulomatous glossitis caused by actinobacillus lignerisii (wooden togue), very severe case

43
Q

this is a tongue cross section. what do you see and what is your differential?

A

there is multifocal areas od pyogranulomatous inflammation surrounded by fibrous connective tissue, likely a bacterial myositis/glossitis caused by actinobacillus lignerisii

44
Q

viral myositis is rare, but one virus that can cause it is:

A

blue tongue virus in sheep causing systemic vasculitis leading to muscle infarcts

45
Q

in regards to parasitic myositis, is there associated disease/clinical signs? what are some species that are associated with parasitic myositis?

A

muscle infection occurs in intermediate hosts usually

neosporum caninum in calves and dogs
cysticercus in cattle, sheep, goats, pigs
sarcocystis in large animals and wildlife

46
Q

what is an example of an immune mediated myositis in horses?

A

following a strep equi infection, antibody complexes deposit in blood vessels causing an immune mediated vasculitis which can lead to muscle hemorrhage and infarction affecting multiple muscles

47
Q

if you have a horse with muscle hemorrhage and infarction, what are two potential diagnoses and how would you tell them apart?

A
  • immune mediated myositis after strep equi infection (multiple muscles affected, no gas)
  • clostridial myositis (more localized, gas)
48
Q

what kinds of animals are prone to double muscling?

A

belgium blues and whipets/greyhound dogs

genetic defect in myostatin gene, increased # of myofibers

49
Q

are diseases of the neuromuscular junction associated with denervation atrophy?

A

NO! growth promotants are still able to get to the muscle so there is do denervation atrophy in these diseases

50
Q

botulism is caused by:
is causes disease by:
animals get this disease by:
who gets it the worst?

A
  • clostridium botulinum
  • blocks release of Ach from nerve synapse resulting in severe flaccid paraylsis, the respiratory muscles become paralysed, death
  • ingestion of preformed toxin like in rodent carcasses that get into feed
  • horses are the most sensitive
51
Q

there are two forms of myasthenia gravis. describe them and the differences between the two

A
  • the first is congenital which is very rare
  • the second is autoantibodies against Ach receptors, leading to muscles that cannot contract resulting in weakness and collpase. often associated with thymus disease/thymoma, cand this disease can lead to aspiration penumonia
52
Q

what kind of ticks cause tick paralysis?

A

Dermacentor and Ixodes

53
Q

a benign tumor of muscle is called:
a malignant tumor of muscle is called: _______, and the place it likes to originate from is ______

A

rhabdomyoma
rhabdomyosarcoma, urinary bladder

54
Q

muscle is not a common site of metastasis for neoplasia, EXCEPT….

A

in horses with melanoma

55
Q

what is equine polysaccharide storage myopathy? grossly what does it look like? how do you diagnose this?

A

abnormal glycogen accumulation in muscles of mostly warmbloods and drafts, likely causing decreased energy in myofibers. these animals are prone to exertional rhabdomyolysis and hind limb pain

gross: pale muscles esp the hind limbs, dark red kidneys from myoglobin, myoglobinuria

have to diagnose using muscle biopsy

56
Q

what is hypokalemic myopathy?

A

a disease of cows, usually with a history of post partum ketosis. anorexia leads to lowpotassium which can cause myonecrosis. the cow may be weak or recumbent with low serum potassum and high CK/AST

57
Q

briefly describe the pathogenesis of milk fever/hypocalcemia in cows and how it causes muscle damage

A

abnormal post partum calcium hemostasis–> hypocalcemia–>weakness and recumbency–>muscle damage from recumbency

58
Q

what is porcine stress syndrome/,alignant hyperthermia? grossly what does it look like?

A

a genetic condition in pigs that are bred for increased muscle and low fat. an abnormal ryanodine receptor leads to excessive muscle contraction. cliniclly they are normal until they are either exposed to halothane anesthesia OR experience high stress, leading to muscle rigidity and high body temperature which progresses to death

gross: muscles are pale, swollen, and appear cooked

59
Q

what is the name of the parasite in dogs that infects young animals in utero and infects the peripheral nervous system and skeletal muscles resulting in denervation atrophy of hinf limb muscles and myositis?

A

neosporum caninum

60
Q

define musular dystrophy

A

inherited, progressive condition with myofibere degernation and necrosis with regeneration

61
Q

what is X linked muscular dystrophy?

A

a genetic condition affecting dogs, defective dystrophin gene, leads to progressive weakness and muscle atrophy, eventually cardiac fibrosis

62
Q

true or false: hypothyroidism in dogs causes skeletal muscle weakness and atrophy

A

true! it is a similar presentation to hypercortisolism

63
Q

what is masticatory myositis?

A

an immune mediated inflammation against type 2 myofibers of the masticatory muscles leading to bilateral swelling, pain, and inability to open the mouth acutely, or symmetrical atrophy of mastication muscles and fibrosis chronically. to diagnose you must do serology to test for the antibody

64
Q

this is jack. what is wrong with poor jack?

A

he has chronic masticatory myositis (can see atrophy of the temporalis and masseter muscles)

65
Q

what is immune mediated polymositis and how it it different from masticatory myositis?

A

it is an immune mediated inflammation that targets the myofibers causing necrosis in MULTIPLE muscles, so all muscles can be affected. with masticatory myositis only the masication muscles are affected

66
Q

what virus in cats may cause an immune mediated myositis?

A

FIV, feline immunodeficinecy virus

67
Q

true or false: cats with hypothyroidism can experience muscle weakness due to hypokalemia

A

false. HYPERTHYROIDISM in cats an cause hypokalemia and resulting muscle weakness, as well as chronic renal disease!

VETM 425 (28 decks)

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