Joints, synovial fluid and cartilage

Question 1

Name the 3 types of joints

Answer 1

fibrous
cartilaginous
synovial

Question 2

3 examples of fibrous joints

Answer 2

cranial sutures
periodontal ligament
interosseus membrane

Question 3

What type of cartilage is in a primary and secondary cartilaginous joint?

Answer 3

primary = hyaline 
secondary = hyaline and fibrocartilage

Question 4

alternative names for a primary and secondary cartilaginous joint

Answer 4

primary = synchondrosis 
secondary = symphysis

Question 5

an example of a primary and secondary cartilaginous joint

Answer 5

primary - epiphyseal growth plate

secondary = intervertebral disc

Question 6

4 common features of a synovial joint

Answer 6

synovial cavity
synovial membrane
fibrous capsule
articular cartilage

Question 7

3 other features which a synovial joint may contain

Answer 7

ligaments
bursae
articular discs

Question 8

List some types of synovial joints and an example of each

Answer 8

plane - facet joint in vertebrae 
condylar - wrist 
hinge - elbow 
saddle - thumb 
pivot - proximal radio-ulnar 
ball and socket - shoulder

Question 9

3 things joint stability is determined by

Answer 9

shape of articulating surfaces
capsule and ligaments
muscles

Question 10

What types of cartilage are in synovial joints and where are they both found?

Answer 10

hyaline lines epiphysis

fibrocartilgae in the fibrous cartilage

Question 11

Briefly describe the superficial later of articular cartilage

Answer 11

flattened chondrocyted produce collagen and glycoproteins

horizontally arranged

Question 12

example of glycoprotein

Answer 12

lubricin

Question 13

Briefly describe the transitional layer of articular cartilage

Answer 13

round chondrocytes produce proteoglycans

diagonally arranged

Question 14

example of proteoglycan

Answer 14

aggrecan

Question 15

is water compressible?

Answer 15

no

Question 16

Are glycoproteins and proteoglycans more protein or carbs?

Answer 16

g - more protein

p - more carbs

Question 17

What is a glycosaminoglycan?

Answer 17

long unbranched polysaccharide which are highly polar and therefore attract water

Question 18

example of GAG

Answer 18

hyaluronic acid

Question 19

average cartilage thickness and the thickness of patella and interphalangeal joint

Answer 19

2-3mm
IP = 1mm
patella = 5-6mm

Question 20

3 A’s of cartilage

Answer 20

avascular
aneural
alymphatic

Question 21

How does cartilage get nourished and remove waste?

Answer 21

via synovial fluid

Question 22

What produces synovial fluid?

Answer 22

synoviocytes in the synovial membrane

Question 23

Does the synovium have an epithelial lining?

Answer 23

no

Question 24

Type A synoviocytes

Answer 24

look like macrophages
remove debris
contribute to synovial fluid production

Question 25

Type B synoviocytes

Answer 25

fibroblast like

main producer of synovial fluid

Question 26

are type A or B synoviocytes the main producer of synovial fluid?

Answer 26

B

Question 27

components of synovial fluid

Answer 27

viscous
hyaluronic acid and lubricin
fluid component from plasma

Question 28

volume and turnover of synovial fluid

Answer 28

small volumes, high turnover

Question 29

3 main functions of synovial fluid

Answer 29

nutrition of cartilage
removal of waste products
lubrication

Question 30

How is the boundary part of lubrication achieved?

Answer 30

glycoproteins (lubricin) bind to receptors on articular surfaces and form a thin film

Question 31

How is the hydrodynamic property of synovial fluid lubrication achieved?

Answer 31

surfaces kept apart by liquid pressure

viscosity changed with load and velocity

Question 32

How is weeping of synovial fluid lubrication achieved?

Answer 32

fluid present in cartilage squeezed into synovial cavity to increase the fluid volume

Question 33

What are bursae?

Answer 33

fluid filled sacs which reduce friction and can become inflamed - bursitis

Question 34

2 main changes of joints with ageing and the overall consequence of this

Answer 34

viscosity of synovial fluid inc. - slow joint move and dec lubrication
water content of cartilage dec.- red. shock absorption
less protection of articular surfaces and increased risk of damage