Lecture 1: Osteoarthritis

Question 1

T/F

The diarthrodial joint is considered an organ

Answer 1

True.

Question 2

Describe the diarthrodial joint

Answer 2

synovial joints allow for motion and are complex

synoviocytes line the membrane

think of it as an organ

Question 3

What does poor lubrication of the joint lead to?

Answer 3

increased friction, which results in increased wear and tear on the joint

Question 4

What causes joints to wear out over time?

Answer 4

trauma

disease

biochemical changes in articular cartilage

poor lubrication

Question 5

What are the 2 functions of the synovium?

Answer 5

lubrication

phagocytosis

Question 6

What do synoviocytes add to the joint fluid?

Answer 6

glycosaminoglycans

hylauronon

Question 7

What is the synovial fluid?

Answer 7

dialysate of blood- ultrafiltrate

Question 8

What are the 2 functions of the synovial fluid?

Answer 8

lubrication and and nutrition of the articular cartilage

Question 9

Describe normal healthy joint fluid:

Answer 9

sticky, has viscosity to it

diseased is watery

Question 10

What is the chief glycosaminoglycan? what does it contribute to the joint fluid?

Answer 10

hyaluronic acid (HA)

gives it its viscocity

Question 11

Osteoarthritis can occur if HA is in low _____ and _____

Answer 11

quality and/or quantity

Question 12

T/F

Articular cartilage is highly vascualr but has no innervation

Answer 12

FALSE

it is avascualr, and has no innervation

Question 13

Chondrocytes receive ____% of their nutrition from synovial fluid and ____% from subchondral bone.

Answer 13

90-93% from fluid

3-10% subchondral bone

Question 14

What type of collagen is present in articular cartilage?

Answer 14

TYPE II

Question 15

Describe the realtionship between HA and proteoglycans

Answer 15

HA is the protein backbone and attached to it are proteoglycans

Think of HA as the terminal and proteoglycans as the planes docked to it

Question 16

Define weeping lubrication:

Answer 16

occurs when cartilage is compressed, ie during movement

Question 17

Define boosted lubrication:

Answer 17

when fluid is sucked back into the cartilage

Question 18

Define boundary lubrication:

Answer 18

binds to superficial cartilage to help with movement

Question 19

______ depletion compromises lubrication

Answer 19

proteoglycan

Question 20

Define osteoarthritis:

Answer 20

non infectious degeneration of articular cartilage

Question 21

What are physical changes associated with OA?

Answer 21

bone formation at synovial membrane

periarticualr fibrosis (joitn thickening

Question 22

What is OA associated with an infection referred to as?

Answer 22

Septic OA

Question 23

What are the clinical sign associated with OA

Answer 23

exercise intolerance

shortened stride

lameness/head bob or bunny hopping

behavior changes

visual/palpable joint effusion

Question 24

Humans tend to get ______ OA while animals typically get ______ OA

Answer 24

primary

secondary

Question 25

What causes secondary OA?

Answer 25

developmental and bone diseases ligament dz- abnormal stability articular function- inflammation causes damage infection trauma surgery can too

Question 26

What is the viscous cycle of OA?

Answer 26

poor lubrication cartilage fibrillation-> fissures inflammation/release of ILs/Cytokines/collangenasee/elastases Depletion of matrix proteoglycans damage to collagen network RESULTS in cartilage degeneration-> poor lubrication etc etc

Question 27

What is the net result of OA?

Answer 27

``` articualr fibrilation cartilage loss subchondral sclerosis osteophyte formation periarticular fibrosis synovitis pain/loss of fx ```

Question 28

T/F OA effects the entire joint but may be pronounced more so in one area

Answer 28

TRUE

Question 29

What are the radio graphic signs of OA

Answer 29

increased soft tissue opacity in the joint space periarticualr bone formation subchondral bone sclerosis

Question 30

T|/F Radio graphs typically overestimate the severity of OA and therefore do not correlate clinically with function

Answer 30

FALSE They tend to underestimate severity

Question 31

If the ______ is addressed, we can help slow OA

Answer 31

Primary problem

Question 32

Once you have diagnosed OA, what do you tell the owner?

Answer 32

We can try some tx to help make sparky more comfortable

Question 33

T/F There is no cure for OA

Answer 33

TRUE

Question 34

T/F Once OA starts it will continue to progress; the best we can do is address the primary problem, and try ti mitigate further damage

Answer 34

TRUE

Question 35

What are the 4 forms of medical management of OA

Answer 35

Weight management Excercise moderation Chondroprotectives NSAIDS

Question 36

What is the goal of weight management? what is it based on?

Answer 36

Lean and fit based on Lab experiments

Question 37

What are the 3 parts to exercise management?

Answer 37

controlled low impact rehab

Question 38

What are some examples of chondroprotectives?

Answer 38

``` Glucosamine Chondroitin sulfate Manganese ascorbate ASU MSM Omega 3 FA ```

Question 39

What are polysulfated glyosaminoglycans?

Answer 39

Adequan from bovine tracheal cartilage IM injection 2x weekly for up to 4 weeks Not clinically shown

Question 40

Why might Hyaluronon injections be beneficial to slowing cartilage degredation

Answer 40

Leaves joint completely in 24 hours, unknown mech of action | had no effect on OA progression or loading in canine stifles

Question 41

How does injection of platelets into joint help combat OA?

Answer 41

increases cytokines and growth factors

Question 42

NSAIDS act to:

Answer 42

inhibit cyclooxygenase pathway effect many systems be careful of side effects

Question 43

T/F for best results tx OA with 2 NSAIDS

Answer 43

FALSE never more than 1

Question 44

____ days for washout between NSAID | ____ days for washout for asprin

Answer 44

4-7 7-10

Question 45

At what point to you opt for surgery with OA and what is the main goal of it?

Answer 45

when medical management has failed unlikely to have addressed primary cause Surgery is to address primary

Question 46

T/F cartilage healing is generally fast

Answer 46

FALSE poor blood supply

Question 47

What is micropicking?

Answer 47

allows blood flow from subchondral bone encourage fibrocartilage formation blood clot/fibrocartilage fill in so bone isnt as exposed

Question 48

What is osteochondral transplant surgery?

Answer 48

large lesion | bone plug insrted into defect supports subchondral bone

Question 49

What is the single most important factor to remember when treating OA in small animals?

Answer 49

OA IS SECONDARY IN NATURE

Question 50

T/F | OA in humans, as with animals is typically secondary in nature

Answer 50

FALSE primary in humans

Question 51

T/F Radiographic signs of OA are fairly consistent with clinical function

Answer 51

False NO correlation

Question 52

T/F medical management is important for tx of OA

Answer 52

TRUE