Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Module 7 > Muscle Pathology > Flashcards

Muscle Pathology Flashcards

(50 cards)

Start Studying
1
Q

what are the types of muscle fibres

A

type 1 and type 2

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

how many mitochondria do type 1 and type 2 have

A

1: many
2: fewer

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

what is the metabolism of type 1 and 2 muscle fibres

A

1: oxidative (aerobic)
2. glycolytic (anaerobic)

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

what type of contraction do type 1 and 2 muscle fibres have

A

1: slow
2: fast

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

which muscle fibres fatigue more easily

A

1: slow
2: more easily

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

which type of muscle is 1 and 2 fibres

A

1: postural
2: propulsive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what colour are type 1 and 2 muscle fibres

A

1: red
2: white

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

what are the fibres like in type 1 and 2

A

1: smallest
2: 2B is largest (fast-contracting, fast-fatiguable, glycolytic) 2A: mixed oxidative-glycolytic; fast-contracting, slow-fatigueing (intermediate)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the mixed mosiac pattern

A

most muscles contain both type 1 and 2 fibres

proportion varies dependent on muscle function

determined by motor neuron

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

which muscle fibre do dogs not have

A

type 2B

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

what is rigor mortis

A

sustained muscle contraction after death

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

what causes rigor mortis

A

absence of adequate ATP production –> actin and myosin cannot be released from eachother

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

how is rigor mortis stopped

A

muscle breakdown (autolysis)

variable onset and resolution depending on intrinsic and extrinsic factors (temp, etc)

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

what is a motor unit

A

myofibres innervated by a single axon

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

how are fine movements produced

A

small motor units –> 1-4 myofibres per axon

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

how are large forces generated

A

large motor units –> 100-150 myofibres per axon

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

how are muscles examined using clinical pathology

A

CK, ALT (AST, LDH less specific)

myoglobin

integrity not function

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

how can muscles be examined using electrophysiology

A

electromyography

electroneurography

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

what are gross examination features of muscle ex vivo

A
  1. size
  2. colour
  3. texture
  4. histological examination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what changes colour changes of muscles indicate

A
  1. pale pink/white: anemia, young animal, ischemic necrosis, mineralization, collagen, fat
  2. red: congestion, hemorrhage, hemorrhagic, necrosis, inflammation, myoglobin staining
  3. green: eosinophils, severe putrefaction
  4. tan-brown: lipofuscin
  5. black: melanosis in calves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what texture changes occur in muscles

Study These Flashcards
A

soft: fat, necrosis
firm: fibrosis
hard: mineralization

22
Q

what needs to be considered when muscles are biopsied

Study These Flashcards
A

certain muscles easier to sample due to longitudinal orientation

  1. type of muscle: proximal/distal
  2. certain muscle/muscle groups: ex. masticatory muscle myositis
  3. type of myofibre
  4. fresh vs. fixed muscle
23
Q

what are response to insult

Study These Flashcards
A
  1. hypertrophy (addition of myofilaments)
  2. atrophy
  3. degeneration and necrosis
  4. regeneration
  5. chronic myopathic change: alterations in myofibre diameter, fibrosis, fat infiltration, aetiology: chronic inflammation, deneration, degenerative myopathy

often cause for changes not clear on histology –> history and ancillary tests required

24
Q

what is atrophy

Study These Flashcards
A

usually reversible

reduced myofibre diameter

25
what is hyaline degeneration
homogenously eosinophilic fibres, loss of striations
26
what does regeneration of muscle depend on
muscle is post mitotic tissue regeneration depends on intact satellite cells and extent of damage to basal lamina
27
what are the steps of regeneration in muscle
basal lamina intact 1. macrophages entre and remove debris 2. satellite cells become myoblasts 3. myoblasts fuse to form myotubes 4. essential structures reformed 5. nuclei move to peripheral position
28
what occurs when the basal lamina is destroyed
if satellite cells survive mutlinucleate muscle giant cells develop
29
what are the types of muscle pathology
1. vascular 2. inflammatory (infectious/immune-mediated) 3. traumatic 4. anomaly/congenital 5. metabolic/toxic 6. idiopathic/iatrogenic 7. neoplastic 8. degenrative
30
what occurs during vascular damage
ischemia 1. occlusion of large blood vessel 2. external pressure on a muscle (downer cow, anaesthesia) 3. internal pressure on a muscle (compartment syndrome) 4. vasculitis/vasculopathy
31
how does inflammatory damage occur
1. penetrating wounds 2. spread from adjacent sites 3. hematogenous
32
what bacteria causes inflammatory damage to muscle
clostridia --\> myonecrosis CI. perfringens, CI. chauvoei, CI. septicum, CI. novyi
33
how does bacteria cause inflammatory damage
toxins --\> damage to myofibrils and vessels leads to necrosis
34
what is pyogenic bacteria
abscesses
35
what parasites cause inflammatory damage
protozoa: Neospora caninum nematode: trichinella spiralis (pigs), larval migrans (dogs) cestode: larval form
36
what are the causes of immune-mediated muscle damage
primarily dogs usually cytotoxic T cells
37
what is masticatory muscle myositis
antibodies againts type 2M myosin and myositigen focal myositis of masticatory muscles
38
what are traumatic injuries
crushing lacterations tearing or ruptures
39
what is the most common muscle to undergo traumatic injury
diaphragm
40
what do traumatic injuries normally cause
damage to basement membrane --\> fibrosis
41
what is X-linked muscular dystrophy
absence of membrane associated cytoskeletal protein dystrophin repeated necrosis and regeneration of fibres progressive weakness and skeletal muscle atrophy beginning within days of birth
42
what is labrador centronuclear myopathy
mutation in gene encoding cell surface protein weakness, gait abnormalities, exercise intolerance
43
what is hyperkalemic periodic paralysis
membrane instability and continuous myofibre activity muscle spasm followed by paralysis
44
what is equine polysaccharide storage myopathy
carbohydrate metabolic disorder recurring exertional rhabdomyolysis, unexpected pelvic limb lameness
45
what are metabolic injuries to muscle
oxidative injury due to loss of antioxidant defense mechanisms
46
what are examples of metabolic injuries
selenium deficiency vit E deficiency "white muscle disease"
47
what are examples of toxic damage to muscle
1. ionophores (monensin in horses) 2. plants multifocal and monophasic/polyphasic necrosis
48
what is exertional (iatrogen) damage
capture myopathy in highly strung wild animal more often: underlying pre-existing conditions (Se deficiency, muscular dystrophy, electrolyte depletion, glycogen storage dx)
49
what is primary neoplasm damage
rhabdomyoma rhabdomyosarcoma
50
what is secondary neoplasm
injection site sarcoma round cell tumours: lymphoma, mast cell tumour infiltrative lipoma carcinoma

Module 7 (50 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions