Cartilage development

Question 1

Contents - hyaline cartilage

Answer 1

• collagen
• PG
• water
• to resist compressive forces

Question 2

Tissues in a synovial joint

Answer 2

• bone
• cartilage
• joint tissue
• synovial membrane
• synovial fluid
• ligament
• tendon

Question 3

What happens with arrest of physis?

Answer 3

shortening or deformity of limb

Question 4

Differentiate valgus and varus deformity

Answer 4

• valgus = lateral deviation

- varus = medial deviation

Question 5

T/F: it is normal for epiphysis to expand during growth

Answer 5

True

Question 6

Define osteochondrosis

Answer 6

in veterinary, this is a term for a group of conditions of developing cartilage and its supporting bone. example is osteochondrosis dissecans (OCD)

Question 7

What happens in OCD?

Answer 7

detachment of a chondral or osteochondral fragment from the articular surface

Question 8

What is subchondral bone cyst (SBC) an example of?

Answer 8

example of osteochondrosis

Question 9

What is peri-articular fragmentation/ fracture?

Example?

Answer 9

• detachment of a chondral or osteochondral fragment from the peri-articular area
• e.g. fragmentation / fracture of medial coronoid processs of canine elbow (FCP or FCMP)

Question 10

What initiates osteochondrosis?

Answer 10

initiated by a vascular problem in the epiphysis –> failure of normal cartilage to bone succession

Question 11

Examples - osteochondrosis in dogs - 3

Answer 11

• OCD
• FCP = Fragmented Coronoid Process
• UAP = Ununited Anconeal Process
• elbow, shoulder, stifle, tarsus (other posible)

Question 12

Signalment - osteochondrosis

Answer 12

all animals are fast growing, all are young

Question 13

Examples - osteochondrosis in horses - 2

Answer 13

• OCD
• SBC
• stifle, tarsus, MCP, PIP, DIP
• shoulder, elbow, carus

Question 14

Example - osteochondrosis in pigs

Answer 14

OCD especially hip

Question 15

Example - osteochondrosis in broiler chickens

Answer 15

OCD stifle

Question 16

Possible tx - juvenile developmental joint complaints

Answer 16

• depends on presentation
• symptomatic
• conservative
• surgical (open or arthroscopy): encourage removal, encourage repair

Question 17

Prognosis - juvenile developmental joint complaints

Answer 17

• variable
• related to formation of OA
• shoulder forms little OA (good prognosis)

Question 18

Differentiate OA in animals from humans

Answer 18

• humans = disease of ageing/degeneration
• animals = usually secondary to primary predisposing disease, worsened or exacerbated with exercise, can be ageing too but usually secondary.

Question 19

Elbow OA - tx

Answer 19

• symptomatic
• conservative
• sx (open or arthroscopy): fragment removal, encourage repair
• novel tx that change anatomy
• prognosis depends of degree of OA formation (may need salvage procedure)

Question 20

Why does osteochondrosis –> OA?

Answer 20

• irritation
• direct cartilage damage
• incongruency, mechanical incompetence
• cycle of reaction
• often temporarily stabilises in young adult

Question 21

List broad categories of primary joint disease

Answer 21

• DEVELOPMENTAL: HD, osteochondrosis
• DEGENERATION (of a specific structure): canine cruciate disease
• INFECTION (septic arthritis)
• TRAUMA: acute or chronic (performance animals)
• IMMUNE-MEDIATED

Question 22

List some primary joint diseases of dogs

Answer 22

• OCD
• FCP (elbow)
• UAP
• elbow, shoulder, stifle, tarsus (others possible)

Question 23

List some primary joint diseases of horses

Answer 23

• OCD and SBC

- stifle, tarsus, MCP, PIP, DCP (shoulder, elbow, carpus)

Question 24

Describe osteochondrosis presentation

Answer 24

• young, fast growing, large, pure bred
• joint effusion (inconsistent)
• often bilateral
• lameness (variable, on and off not uncommon, related to pain and loss of ROM)
• subclinical disease is possible

Question 25

Prevention - ED

Answer 25

- large genetic component - large subclinical population (silent carriers) - use screening system to remove carrier animals - similar system for hip dysplasia

Question 26

Animals affected by HD and ED

Answer 26

- numerous large (and small) dog breeds - seen in some cats - Norwegian Dole ponies

Question 27

When do HD CS tend to start?

Answer 27

in affected breeds from 5 months onwards

Question 28

Typical HD presentation

Answer 28

- puppies of affected breeds from 5mo + - lameness or gait abnormality, related to pain or mechanical inefficiency - inability to manage some types of exercise (stairs, car) - bilateral signs - instability of the coxofemoral joints and pain on manipulation

Question 29

What is canine elbow dysplasia (ED)?

Answer 29

- osteochondrosis is the primary disease in this SYNDROME - ED includes: * OCD * FCP/ FCMP * UAP * secondary OA = a combination of all/some of these is ED