OC Flashcards
Retained cartilaginous core suggests damage to what area?
resting zone cartilage canal vessels and metaphyseal blood supply
List palliative, reparative, and restorative techniques to treat OCD
Palliative & reparative:
curettage
spongialization
abrasion arthroplasty
forage (osteostixis)
microfracture (+/- growth factor or matrix augmentation hyaluranon)
Restorative:
fragment reattachment
mosaic plasty
osteochondral autograft transplantation
osteochondral resurfacing
What are 2 theories for diffuse OC development
dyschondroplasia - abnormal maturation of chondrocytes
osteopenic subchondral (overnutrition) bone can’t support cartilage
What are 4 grades/classification of OCD
- surface normal; slightly thick cartilage; minimal subchondral defect
- surface mottled; thick cartilage; small cleft between cartilage/subchondral bone
- discoid elevation cartilage surface; large cleft; sclerotic subchondral bone
- partially detached cartilage flap/joint mice
What is type 1 vs type 2 OC lesions
Type 1 - center of affected articular surface away from vascular attachments
Type 2 - joint margin and retain vascular attachment
Where do type 1 vs type 2 each occur
Type 1 - caudal humeral head, medial humeral condyle, lateral femoral condyle
Type 2 - medial and lateral talus
What is a theory for focal OC
vascular trauma or necrosis of subchondral bone or epiphyseal cartilage canals
Name the 4 zones of growth plate
resting, proliferative, hypertrophic, mineralization
What are the layers/components of articular epiphyseal complex
Outer layer:
1-superficial zone
2-transitional
3-radial
4-zone of calcified cartilage
Inner layer:
1-disorganized/no___ columnar zone
2-chondroepiphysis abundant vasculature
Where is tidemark?
between radial and calcified zone
Explain difference of OC latens, manifesta, dissecans
latens - early microscopic lesion
manifesta - subclinical lesions macroscopically and seen on rads
dissecans - loose cartilage flap
Which sex predominates (except which joint)
males > females except tarsus
what is Hueter-volkmann law
growth is retarded by increased mechanical compression and accelerated by reduced loading in comparison with normal values
what are 3 overlapping stages that involve the articular cartilage layer in developing OA?
- extracellular matrix degrades: water content increases leading to aggrecan size decreases. this causes collagen network to become compromised and leads to cartilage stiffness decrease
- chondrocytes enhance proliferation and metabolic activity
- chondrocytes can’t keep up their repair activity - complete loss of cartilage
end result of COX (-) is what?
to decrease PGE 2
what are surgery management options of OA
joint debridement and micropik sx
joint replacement
arthrodesis/salvage
what breed is predisposed to systemic lupus erythematosus?
nova scotia ducking tolling retriever
are osteophytes present on joint films common or uncommon with nonerosive disease
uncommon
list 4 types of nonerosive IMPA and % frequency?
type 1 - most common; idiopathic - 50% of those without multisystem
type 2 - with infection remote from joint - 25%
type 3 - GI disease 15%
type 4 - neoplastic
for type 1 IMPA (non-erosive) what is cure rate?
56%
31% relapse rate
for type 2 IMPA (non-erosive) where are the infection site located
endocarditis, respiratory, skin, abscess, genitourinary
for drug induced IMPA, what are the drugs and breed predisposition?
sulfonamides, penicillin derivative, erythromycin, lincomycin, cephalosporins
Doberman
prognosis for breed-associated IMPA (non-erosive)
sharpei-fever = poor (goes to kidneys)
what is another breed affected besides sharpei
japanese akita
how do you diagnose rheumatoid arthritis
rads - erosive changes in joints
rheumatoid factor in serum (IgM +/- IgA)
the ‘II’ criteria evaluated
classic - 7 criteria fulfilled, definitive - 5
what are 2 other erosive IMPAs?
polyarthritis of greyhounds
feline chronic progressive polyarthritis
what are risk factors for bacterial infective arthritis
previous sx; pre-existing joint disease
for bacterial infective arthritis how long do you treat with antibiotics
until cell count within normal range and neutrophils at or < 3% on synovial fluid count
