BONE-05

Question 1

Question 2

1. osteochondrosis is what?

Answer 2

1. multifocal disorder of epiphyseal (growth) cartilage that occurs in both the articular-epiphyseal cartilage complex (immature joint cartilage covering the ends of growing long bones) and the growth plate (physis) in humans and in a variety of animal species.

only occurs during development




Question 3

(Osteochondrosis)

(Prevalence)

1. really common in what?
2. what else have it?

Answer 3

1. pigs (100% have lesions)
2. horses, large dogs, poultry,

others (humans, cattle, sheep, cats)

Question 4

Osteochondrosis

1. studied mainly in what stage in both humans and animals?
2. In humans, name of disease varies with site
3. In all species, multiple names for the disease

• Osteochondritis dissecans – Osteochondrosis dissecans – Dyschondroplasia
  – OCD

don’t memorize these names

Answer 4

1. chronic

Question 5

(Osteochondrosis)

1. among all species in which they have been examined, the early (subclinical) lesions in the articular-epiphyseal carilage comples are what?

2. suggesting what?

Answer 5

1. remarkably similar (as are those in the growth plate)

2. pathophysiology of this condition essentially the same in all species

Question 6

II. Epiphyseal Cartilage/Normal Endochondral Ossification

• Epiphyseal (growth) cartilage

Vascular hyaline cartilage (growth plate and epiphyseal cartilage portion of the A-E complex)

1. Growth plate responsible for what?
2. A-E complex responsible for what?

Answer 6

1. longitudinal bone growth
2. shape of ends of growing long bones

Question 7

Epiphyseal (growth) cartilage

1. destined to do what?
2. Composed of four morphologically and biochemically distinct zones

what are they?

Answer 7

1. ossify by endochondral ossification, becoming bone in the mature individual
2. resting, proliferating, hypertrophic, and calcifying zones

Question 8

Endochondral ossification

1. Orderly maturation of cells in the four zones is required
2. Cartilage calcification followed by what?
3. Osteoprogenitor cells produce what on calcified cartilage matrix?
4. Epiphyseal cartilage must be what for process to occur?



Answer 8

2. vascular invasion
3. osteoid
4. viable

Question 9

Because epiphyseal cartilage is absent in the adult, the underlying lesions of osteochondrosis can only occur in what?

Answer 9

growing individuals (although clinical signs may not be evident until adulthood)

Question 10

III. Vascular Supply to Epiphyseal cartilage

1. articular cartilage is vascular or avascular?
2. Epiphyseal cartilage is supplied by blood vessels within what?

Answer 10

1. avascular

2. cartilage canals

Question 11

(Cartilage Canals)

1. Channels containing blood vessels, nerves, and possibly lymphatics
2. Arise mainly from what?
3. Some arise from what?
4. Present at birth, and gradually decrease in number and extent with increasing age and weight
5. dissapear completely by when?

Answer 11

2. the perichondrium
3. subchondral bone
4. several months of age

Question 12

(Cartilage canals)

(chondrification)

1. physiological process
2. Lumens of cartilage canal vessels fill with what?
3. associated with pathological changes in epiphyseal cartilage?

Answer 12

2. cartilage
3. no

Question 13

(Cartilage Canals)

1. Viability of epiphyseal cartilage highly dependent on what?
2. In contrast, adult articular cartilage derives almost all of its nutrition from what?

Answer 13

1. blood supply
2. synovial fluid (with a minor supply from vessels in subchondral)

Question 14

III. Morphology of lesions of OC

1. In both the articular-epiphyseal complex and the growth plate, lesions of osteochondrosis are composed what?

Answer 14

1. focal areas of retained cartilage that are not converted to bone by endochondral ossification

Question 15

(A-E Complex Lesions)

1. Earliest lesion composed of what?

often centered on what?

Are Overlying articular cartilage and subjacent epiphyseal bone affected?

2. In more chronic lesions, area of necrosis causes delay in what?

and marked reaction in what?

Answer 15

1. focal area of necrotic epiphyseal cartilage

on a necrotic cartilage canal blood vessel

no

2. endochondral ossification
3. subjacent bone

Question 16

(A-E complex lesions)

1. Early lesions may heal completely by what?

Answer 16

1. gradual incorporation of the necrotic cartilage into the subchondral epiphyseal bone

Question 17

Question 18

Answer 18

Question 19

SKIPPING FROWTH PLAGE

(Growth Plate Lesions)

1. not evident until there is failure in what?
2. Composed of focal accumulation of what?
3. Majority of growth plate lesions heal uneventfully



Answer 19

1. endochondral ossification
2. viable hypertrophic chondrocytes (Similar to tibial dyschondroplasia)

Question 20

SKIPPING GROWTH PLATE

(Growth Plate Lesions)

1. Clinical signs may result from what or what

leading to what?

2. As in A-E complex, there typically is marked myelofibrosis and remodeling of trabecular bone subjacent to chronic lesions

Answer 20

1. pathologic fractures within the thickened growth plate or from incongruity of growth rates,

angular limb deformities

Question 21

DON:T LEARN GRWOTH PLATE

Question 22

just read the rest…. make sure to really know the two sumary slides at the end!