Synovial (True) Joints

Question 1

Hoe can joints be classified?

Answer 1

• number of bones involved in a joint
• the degree of movement possible
• the form of the joint surfaces

Question 2

What are the three common features that all synovial joints share? In Latin?

Answer 2

• joint capsule (capsula articularis)
• joint cavity (cavum articularis)
• hyaline joint cartilage (cartiligo articularis)

Question 3

How do you say “joint” in Latin?

Answer 3

articularis

Question 4

What is the name for the hyaline joint cartilage in Latin? What does it do?

Answer 4

hyaline joint cartilage = cartilago articularis
- it covers the end of the two or more bones forming the joint

Question 5

What two layers is the joint capsule composed of? And in Latin?

Answer 5

• the outer fibrous layer (stratum fibrosum)
• inner layer: synovial membrane (stratum synoviale)

Question 6

What does the structure and thickness of the outer fibrous layer depend on? What is its Latin name?

Answer 6

• stratum fibrosum
• depends on the mechanical load placed in the area

Question 7

What can the fibrous layer contain? What is its Latin name?

Answer 7

• capsule ligaments
• stratum fibrosum

Question 8

What is the purpose of the synovial inner membrane? What is its Latin name?

Answer 8

• stratum synoviale
• lines the joint cavity and is supplied with cells, blood vessels, and nerves

Question 9

What does the synovial membrane appear as (colour)? What is its Latin name?

Answer 9

• stratum synoviale
• ivory colour with a slight yellow tinge

Question 10

What kind of accessories does the synovial membrane contain? Latin names?

Answer 10

• synovial villi (villi synoviales)
• synovial folds (plicae synoviales)

Question 11

How do you say “synovial folds” in Latin?

Answer 11

plicae synoviales

Question 12

What further subdivisions does the synovial membrane have?

Answer 12

1) Inner synoviocytes layer- intima synovialis (comprised of cover cells, the synoviocytes)
2) subsynovial layer- startum subsynoviale

Question 13

What two types of cells exist in the inner synoviocytes layer? Latin name? What are they responsible for?

Answer 13

1) type-A synoviocytes (responsible for phagocytosis)
2) type-B synoviocytes (produce and secrete proteins)

Question 14

What are joints filled up with? What colour? What function?

Answer 14

• synovial fluid
• pale yellow, viscous fluid
• primary purpose: lubricate the joint, reducing friction between articular surfaces

Question 15

What else, apart from synovial joints, does synovial fluid fill?

Answer 15

tendon sheaths (is found in tendon bursae)

Question 16

Why does hydrarthrosis ocuur?

Answer 16

due to the increased production of synovia

Question 17

What is synovial fluid composed of?

Answer 17

hyaluronic acid, sugar, electrolytes, enzymes
- involved in nutrient supply of cartilage

Question 18

What are “free joint bodies”? What is a different name?

Answer 18

• “joint mice”
• free-swimming intraarticular pieces of cartilage or bone resulting from a chip fracture of ossification of synovial villi.

Question 19

What is joint cartilage? Where is it thick? Where is it thin, thick? What is it attached to?

Answer 19

thin- concave joint
thick- convex joint

it is attached to a thin subchondral bone layer.

Question 20

What does the hyaline cartilage matrix do?

Answer 20

• absorbs shock,
• is flexible, possesses viscoelastic properties

Question 21

What does joint cartilage lack?

Answer 21

nerves, blood vessels (with a few exceptions).

Question 22

How is articular cartilage divided?

Answer 22

1) superficial zone
2) intermediate zone
3) radial zone
4) calcified zone

Question 23

What is the superficial zone of articular cartilage made out of?

Answer 23

tightly woven collagen fibres

Question 24

What is the radial zone of articular cartilage made out of?

Answer 24

cartilage fibres that unite to form radially organised bundles

Question 25

What is the function of the calcified zone of the articular cartilage?

Answer 25

this structure guarantees a strong attachment of the cartilage to the bone structure.

Question 26

What lies beneath the joint cartilage?

Answer 26

the subchondral bone plate

Question 27

What is the metabolism of joint cartilage?

Answer 27

anaerobic

Question 28

How is cartilage supplied with nutrients?

Answer 28

MAIN: diffusion
SIDE: blood vessels of the bone marrow

Question 29

What are joints strengthened by? In Latin?

Answer 29

capsular joint LIGAMENTS (ligamenta articularia)

Question 30

How are joints classified depending on the number of bones involved in the joint?

Answer 30

1) SIMPLE JOINTS (2 bones only)
2) COMPOSITE JOINTS (2+ bones)

Question 31

How are joints classified depending on the degree of possible movement?

Answer 31

1) UNIAXIAL JOINTS (hinge and vivot joint)
2) BIAXIAL JOINTS (saddle and ellipsoidal joint)
3) MULTIAXIAL JOINTS (ball and socket and and spheroidal joint)
4) TIGHT JOINTS (sacroiliac joint)

Question 32

What is a different name for the ball and socket joint?

Answer 32

spheroidal joint

Question 33

What is the cotyloid joint?

Answer 33

a socket joint where the cavity covers more than half of the ball.

Question 34

What is the ellipsoid joint? What is its different name?

Answer 34

an oval ball and socket joint.
- condylar joint

Question 35

What is the saddle joint?

Answer 35

opposing surfaces are reciprocally concave and convex.

Question 36

What is the plane joint?

Answer 36

gliding joint