joints and muscles (Dark)

Question 1

synovium

primary reponse to injury

Answer 1

• hypertrophy
• arthritis
• osteoarthritis
• infectious dz

Question 2

Pannus

Answer 2

• granulation tissue on articular surface
  
  • can damange underlying cartilage
  • can progress to ankylosis

Question 3

Cartilage damage

Answer 3

• Stage one: Fibrillation
  
  • forms vertical clefts in cartilage
  • dull, yellow-brown cartilage
• Stage two: Eburnation
  
  • polishing exposed subchondral bone
• Stage three: Osteophytosis
  
  • bony projection
  • more bone production for stabilization
• Stage four: Joint mice
  
  • broken off osteophyte or articular cartilage

Question 4

Arthritis

Inflammatory

Answer 4

• Inflammatory
  
  • Acute:
    
    • penetrating wound
    • septicemia
  • Chronic:
    
    • immune mediated (sharpei fever)
    • Lupus
    • viral dz

Question 5

Osteoarthritis

Answer 5

• Degenerative joint disease (DJD)
• Typically aging lesion
  
  • fibrillation
  • cartilage erosion
  • osteophytosis
  • eburnation
  • synovial hyperplasia
• Mechanical/biochemical aspects
  
  • decreased proteoglycan synthesis
  • inc metalloenzyme synthesis - degrade proteoglycans

*DJD check viscosity of joint fluid

Question 6

Osteochondrosis dessicans (OCD)

Answer 6

• Osteochondrosis
• area of thickened cartilage
• OCD when the flap breaks off

Question 7

Neoplasia

Answer 7

• Synovial cell carcinoma
  
  • can be lytic
  • not usually bony proliferation
  • usually joints on long bones

Question 8

IVDD

Answer 8

• Degeneration
  
  • annulus fibrosis cracks, tears, or can rupture
  • releases nucleus pulposus
  • Types
    
    • Type I - sudden
      
      • more common in chondrodysplastic breeds
    • Type II - gradual

*spinal lesion dev: conscious proprioception goes first, deep pain goes last

Question 9

Dural ossification

Answer 9

• ossifying pachymeningitis
• generally incidental
  
  • may interfere with some imaging

Question 10

Hip dysplasia

Answer 10

• Degenerative, non-inflammatory
• Generally large-breed dogs
• deformation of joint
  
  • sublux of femoral head

Question 11

Elbow dysplasia

Answer 11

• degenerative, non-inflammatory
• generally large-breed dogs
  
  • GSD
• ununited anconeal process
• fragmented medial coronoid process
• OCD of elbow

Question 12

Normal muscle

Answer 12

• Myofibers
  
  • single muscle cells
• peripheral nuclei
• striations
• high blood supply

Question 13

Type I muscle fibers

Answer 13

• slow twitch
• large number mitochondria
• postural and sustained activity

Question 14

Type II muscle fiber types

Answer 14

• Tast twitch
• fewer mitochondria
• rapid activity

Question 15

Classification of muscle injuries

TQ

Answer 15

• Distribution
  
  • focal
    
    • HBC example
  • mulitfocal
    
    • Toxin example
• Timeline
  
  • Monophasic
    
    • all injury looks like same timeframe
  • polyphasic
    
    • old and new lesions => indicates ongoing exposure

Question 16

Muscle response to injury

Answer 16

• hypertrophy
• atrophy
• degeneration
• necrosis
  
  • calcification
• regeneration
• fibrosis

Question 17

Myoglobinuria

Answer 17

• intense exercising (crossfit)
• recent m. damage
• in CK

Question 18

Hemoglobinuria

Answer 18

• anemia
• evidence of RBC lysis
• dec PCV

Question 19

Muscle damage

circulation

Answer 19

• downer cattle
• equine anesthesia
  
  • post anesthetic myopathy
  • lots of factors

Question 20

Muscle damage

Myositis

Answer 20

• Bacterial
  
  • typically clostridium
  • abscesses
• Parasitic
  
  • toxoplasma gondii
  • trichinella spiralis
  • sarcocystis spp

Question 21

Muscle damage

myositis

Answer 21

• autoimmune
  
  • systemic lupus erythematosus
  • polymyositis
  • purpura hemorrhagica
  • others

Question 22

Limberneck in ducks

Answer 22

botulism

Question 23

Congenital myopathies

Answer 23

• malignant hyperthermia
• muscular dystrophy
• equine rhabdomyolysis
  
  • sporadic
  • polysaccharide storage myopathy
  • recurrent exertional rhabdomyolysis
• Hyperkalemic periodic paralysis (HYPP)
• Fainting goats
• Splaying

Question 24

Exertional myopathy

Answer 24

• capture myopathy
• disuse
  
  • cast

Question 25

Nutritional myopathies

Answer 25

• malnutrition
  
  • atrophy
• vitamin E / selenium deficiency
  
  • white muscle disease

Question 26

Muscle damage

Toxin

Answer 26

• monensin
  
  • horses

Question 27

Neoplasia

Answer 27

• Rhabdomyoma
  
  • benign, rare
• Rhabdomyosarcoma

Question 28

Muscle damage

Denervation

Answer 28

• Brachial plexus avulsion
• laryngeal hemiplegia
  
  • horses and dogs