Pathology - Test 2 (Joint Pathology)

Front 1

strain

Back 1

mild stretch of the joint capsule

Front 2

sprain

Back 2

stretching of the joint capsule and associated ligaments without displacement of the joint surfaces; ligaments may tear

Front 3

subluxation

Back 3

incomplete separation of joint surfaces; partial tearing of capsule often occurs

Front 4

luxation

Back 4

complete separation of the joint surface; joint capsule is completely torn

Front 5

is djd infectious?

Back 5

no - noninfectious degeneration of articular cartilage occuring over many months

Front 6

what may DJD occur secondarily to?

Back 6

-aging
-conformational or acquired developmental defects such as hip dysplasia, patellar luxaion, osteochondrosis, aseptic necrosis of the femoral head
-trauma
-inflammatory arthritis which alters the synovial fluid and cartilage
-excessive wear due to overuse or weight bearing stress (athletic animals)

Front 7

give the sequence of events that occurs with DJD.

Back 7

(1) release of lysozomal enzymes from inflammatory cells, synovium and damaged chondrocytes
(2) release of prostaglandins
(3) proteoglycans that form the matrix around chondrocytes are reduced
(4) eburnation
(5) subchondral bone becomes thickened (increased bone deposition in response to loss of cartilage) = sclerosis
(6) subchondral bone cysts may form
(7) lipping occurs
(8) osteophytes are formed
(9) joint capsule thickens and the synovium proliferates
(10) cartilage defects fill in with fibrocartilage

Front 8

eburnation

Back 8

-from continuous contact of denuded joint surfaces
-produces a poliched appearance to the exposed subchondral bone
-seen in DJD

Front 9

What is the gross appearance of DJD lesions early on.

Back 9

cartilage is dull, yellow and soft
-surface is rough and erosions and ulcers develop
-then eburnation occurs

Front 10

What is the microscopic appearance of DJD?

Back 10

erosions are seen as flaking and fibrillation (disruption) of the superficial layers of cartilage
-fissures also develop (vertical clefts in the cartilage)

Front 11

What is the gross appearance of DJD lesions early on.

Back 11

cartilage is dull, yellow and soft
-surface is rough and erosions and ulcers develop
-then eburnation occurs

Front 12

lipping

Back 12

proliferation of cartilage at the joint margins

Front 13

osteophytes

Back 13

new bone formation occurs at the joint margins along the insertion of tendons and ligaments and joint capsule insertions

Front 14

In DJD, does the damaged hyaline cartilage regenerate?

Back 14

no - cartilage fills in with fibrocartilage

Front 15

ringbone

Back 15

-DJD of interphalangeal joints of forelimbs of horses characterized by excessive osteophyte production forming a ring around the end of the bone

Front 16

spavin

Back 16

DJD of the tarsus in horses and cattle

Front 17

navicular disease

Back 17

DJD of the navicular bone affecting the forelimbs of horses
-abnormal foot conformation predisposes to this condition

Front 18

spondylosis

Back 18

-DJD
-development of osteophytes on the ventral and lateral aspects of adjacent spinal vertebrae
-may be incidental, but may cause problems
-bony bridging of the ventral vertebral bodies may occur

Front 19

discospondylitis

Back 19

infectious disease of the intervertebral disks of large dogs that appears similar grossly to spondylosis
-affects the disks and endplates of the vertebrae (caused by Brucella or Staphylococcus)

Front 20

intervertebral disk disease

Back 20

-in chondrodystropic breeds
-degeneration of intervertebral disks
-gelatenous disk undergoes premature degeneration with formation of cartilage and mineralization
-decreased flexability of disk and prone to herniation or rupture

Front 21

What is the cause and manifectation of infectious arthristis?

Back 21

(1) hematogenous (bacterial) is most common in young animals
-multiple joints are involved

(2) also can be caused by direct penetration of a joint or by extension from infectioun in adjacent soft tissue
-one joint affected

Front 22

What does infectious arthritis look like grossly?

Back 22

-bacterial infections produce a purulent or fibrinous exudate in the joint depending on the virulence and duration

Front 23

IS infectious arthritis more common in small or large animals?

Back 23

large

-small animals Borrelia burgdorferi (Lyme Disease) is the most common cause

Front 24

Name a common cause of infectious arthritis in all large animals.

Back 24

Streptococcus

-Salmonella in horses and cattle
-Erysipelothrix in swine and sheep

Front 25

What is an important cause of infectious arthritis in goats?

Back 25

caprine arthritis-encephalitis virus ( a retrovirus)

Front 26

What is the pathology of infectous arthritis?

Acute

Chronic

Back 26

Acute: hyperplasia and congestion of synovium with exudate in the joint cavity (early articular cartilage is not damaged)

Chronic:thickening of synovium, producing a villus appearance and thickening of joint capsule
-cartilage is eroded and the infection may extend to tissues and bone (osteomyelitis)
-pannus formation

Front 27

pannus

Back 27

fibrous granulation tissue forms over cartilage surface
-occurs in infectious arthritis

Front 28

What happens in severe, long cases of infectious arthritis?

Back 28

ankylosis

Front 29

ankylosis

Back 29

fusion of the joint by fibrous tissue and bone

Front 30

Is Rheumatoid arthritis erosive or not?

Back 30

Erosive

Front 31

rheumatoid arthritis

Back 31

-chronic immune mediated disease where antibodies, Rheumatoid factors, form against IgG in serum and synovium producing a diffuse lymphoplasmacytic inflammation in the synovium

Front 32

what are the antibodies called that form against IgG in serum and in the synovium?

What type of inflammation occurs in this disease?

Back 32

Rheumatoid factors

-lymphoplasmacitic

Front 33

What leads to inflammation in RA?

Back 33

formation of immune complexes, release of lysozymal enzymes and degeneration of cartilage

Front 34

What is the progression of RA?

Back 34

-immune complexes activate complement leading to inflammation ...
-villous hyperplasia of synovium and thickening of joint
-pannus and severe ankylosis of joint
-subchondral bone loss with cysts (decreased density radiographically)

Front 35

How do joints appear with RA?

Back 35

-enlarged due to fibrosis
-loss of density

Front 36

Is lupus erosive or not?

Back 36

nonerosive

Front 37

systemic lupus erythematosus

Back 37

-a chronic, immune mediated disease in which circulating immune complexes are deposited in joints

-less cartilage damage than RA

Front 38

What are antibodies in lupus directed against?

Back 38

-against nuclear antigens and called antinuclear antibody (ANA)

Front 39

What are some manifestations of lupus?

Back 39

-Hemolytic anemia, renal disease, vesicular dermatitis

Front 40

What is the important neoplasa of the joints?

Back 40

synovial sarcoma - seen in large joints of the limbs of dogs

-also in soft tissue and tendons arounf joints where synovium surrounds tendon sheaths and bursa

Front 41

What is the recommended treatment for synovial sarcoma?

Back 41

amputation with metastiasis in 25% of patients (it is slow)