Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
39 Cards in this Set
- Front
- Back
|
What are the two main categories of joint disease in domestic animals? How do they differ?
|
noninflammatory
inflammatory *differ due to etiology and whether inflammatory mediators are present at the onset of the problem |
|
|
What are causes of noninflammatory joint disease?
|
osteoarthritis (DJD)
trauma to joint subluxation/ luxation meniscal disorder developmental joint disease |
|
|
What are some causes of inflammatory joint disease?
|
infectious arthritis (bacterial, mycoplasmal, viral, fungal etc)
immunologic |
|
|
What are the two main types of synovial joints?
|
high motion
low motion-high load |
|
|
Why is some degree of motion essential to cartilage integrity?
|
circulates synovial fluid that nourishes the cartilage cells
|
|
|
What repair mechanisms exist for cartilage?
|
fibrocartilage or fibrous tissue formation
* Cartilage cannot regenerate! |
|
|
What are the five zones of mature articular cartilage?
|
tangential
transitional radial calcified cartilage subchondral bony plate |
|
|
What type of collagen is in articular cartilage and what is it's function?
|
type II
provides structural framework anchors amorphous matrix and chondrocytes provides toughness to articular surface |
|
|
What is the function of water in the cartilage matrix?
|
transport of nutrients/ waste
provides resiliency lubrication |
|
|
What is a "squeeze film"?
|
lubricating fluid that can be displaced during joint motion
-allows low friction gliding motion of joints |
|
|
What can depress cartilage matrix synthesis and accelerate destruction?
|
trauma
corticosteroids inflammatory mediators |
|
|
What is the result of decreased proteoglycan synthesis in a joint?
|
decreased amounts of water and decreased joint turgor (less lubrication etc)
|
|
|
What is the function of articular cartilage and the subchondral bony plate?
|
diffuse and buffer forces
distribute force over a larger area shock absorption and direction to cortical bone |
|
|
What is joint fluid composed of?
|
blood ultrafiltrate of water and essential nutrients
hyaluronate *VERY FEW inflammatory cells! |
|
|
What is the function of joint fluid?
|
nourish cartilage
provide lubricating film reduce friction via hyaluronate |
|
|
What is primary DJD?
|
idiopathic age related chronic progressive deterioration of a joint with loss of function
|
|
|
What is commonly affected by primary DJD?
|
large paired major weight bearing joints
|
|
|
What is secondary DJD?
|
occurs in any age of animal affected by a preexisting joint disease
-due to repetitive injury |
|
|
Is symmetry of lesions expected with secondary DJD?
|
not necessarily, because it is often traumatic or due to abnormal conformation or usage
|
|
|
which two neurotransmitter systems of the brainstem reticular formation are associated with ANS control?
|
acetylcholine, noradrenaline
|
|
|
How are secondary and primary DJD distinguished?
|
recognition of the primary inciting lesion
history of predisposing disorder |
|
|
What are the gross changes associated with DJD?
|
degeneration of articular cartilage
fibrillation eburnation subchondral cyst formation osteophyte/enthesophyte formation chronic synovitis fibrosis of the joint capsule |
|
|
What does degeneration associated with DJD look like histologically?
|
loss of proteoglycan
disruption of cartilage fibers loss of tangential and transitional zones of the articular cartilage (to varying degrees) |
|
|
What does fibrillation look like histologically?
|
linear splitting of collagen fibers in the radial zone
|
|
|
What does eburnation look like histologically?
|
partial to complete loss of radial zone
exposure of calcified cartilage "polishing" of exposed calcified cartilage and/or bone |
|
|
How does trauma cause DJD?
|
direct damage of chondrocytes increases release of MMPs and may reduce the rate of cartilage synthesis
|
|
|
How does synovitis occur in DJD?
|
debris from deteriorating surfaces cannot be cleared, chronically irritates the synovium
|
|
|
How does the synovium respond to irritation?
|
serous exudate is released
enzymes and cytokines are released (degrade cartilage matrix etc) |
|
|
Explain the vicious cycle of DJD
|
debris from the deteriorating surface causes inflammation
inflammation triggers further cartilage degradation degraded products incite even more inflammation |
|
|
what are the consequences of loss of intercostal muscle function?
|
diphragmatic breathing, impairment of coughing and effective clearance of secretions (commonly leads to atelectasis), V/Q mismatch
|
|
|
How do bone cysts develop in mature horses?
|
unrepaired microfractures allow joint fluid into the bone
|
|
|
How does lipping occur in DJD?
|
instability of the joint triggers chondrocyte proliferation
endochondral ossification occurs, forming a bony lip to support the growing cartilage lip *may fragment, cause bone chips |
|
|
What changes occur with chronic synovitis in DJD?
|
hypertrophy/hyperplasia of synovial intimal cells
congestion, edema, fibrosis villous hypertrophy formation of synovial chondromas |
|
|
What are the consequences of chronic DJD?
|
permanent thickening of the joint capsule
reduction in the normal range of motion of the joint |
|
|
What changes occur with DJD in high load- low motion joints?
|
full thickness cartilage necrosis
joint fusion |
|
|
Why is medical intervention needed with DJD of high load- low motion joints?
|
most animals cannot achieve fusion without help
|
|
|
What is high ringbone?
|
pastern joint fusion
|
|
|
What is low ringbone?
|
distal interphalangeal joint fusion
|
|
|
What is bone spavin?
|
fusion of distal intertarsal and tarsometatarsal joints
|
