A&p.articulations.2

Front 1

what are articulations?

Back 1

how bones interact with each other where those bones are interconnected

Front 2

what are the three functional categories of joint design and movement?

Back 2

1. synarthrosis (joint that has no motion)
2. amphiarthrosis (joint that has little motion)
3. diarthrosis (joint that has free movement

Front 3

what type of joints are diarthrosis?

Back 3

all are synovial joints

Front 4

what are synarthrotic and amphiarthrotic joints?

Back 4

-they are relatively simple structures
-they direct connections between two or more bones
- they are very strong without most range of motion due to fibrous or cartilaginous
- they have accessory structures

Front 5

what are diarthrotic joints?

Back 5

-found in the knee
-they complex in structure
-they permit greatest range of motion
-they are all synovial joints

Front 6

what are the three components of synovial joints?

Back 6

1. articular cartilages
2. synovial fluid
3. joint capsule (articular capsule)

Front 7

what are articular cartilages?

Back 7

-they cover opposing bone surfaces
-have no perichondrium
-slick and smooth which reduces frictin due to no perichondrium and more water in the matrix

Front 8

what other type of cartilage do reticular cartilages resemble?

Back 8

hyaline cartilage

Front 9

why does reticular cartilage resemble hyaline cartilage?

Back 9

because it is left over from fetal skeleton and the matrix contains more water comparatively than in the fetal skeleton

Front 10

what is articular cartilage separated by?

Back 10

a thin film of synovial fluid

Front 11

what are the functions of synovial fluid?

Back 11

-lubrication- reduces friction
-nutrients and takes wastes away from cartilage as well as the cells lining
-shock absorption

Front 12

what is shock absorption?

Back 12

less pressure on bones because water takes it away

Front 13

what is synovial fluid similar in composition to?

Back 13

similar to ground substance in loose connective tissues (like areolar)
-looks like uncooked egg whites

Front 14

how is synovial fluid similar to the ground substance in loose CT?

Back 14

-it consists of hyaluronic acid produces by cells lining the cavity
-it contains interstitial fluid from blood plasma from CT of the lining of cavity (inner synovial membrane)

Front 15

where is synovial fluid produced?

Back 15

at the synovial membrane

Front 16

what are the two layers of the synovial membrane?

Back 16

-an inner layer that consists of areolar CT
-an incomplete epithelial layer

Front 17

where does the synovial fluid circulate?

Back 17

-from the areolar tissue to the joint cavity
-interstitial fluid circulates

Front 18

what does synovial fluid percolate through?

Back 18

percolates through articular cartilages (imagine articular cartilage is like a sponge)

Front 19

how does synovial fluid percolate through articular cartilages?

Back 19

it sucks in interstitial fluid after it circulates from areolar tissue and then exerts pressure on the tissue

Front 20

what are the functions of joint capsule (articular capsule)?

Back 20

-surrounds joint enclosing the cavity and synovial fluid
-interconnects the articulation bones

Front 21

describe the joint capsules membrane:

Back 21

its a two layered membrane that consists of an inner synovial membrane and an outer fibrous layer

Front 22

explain the outer fibrous layer of the joint capsules membrane:

Back 22

dense and fibrous; dense irregular CT so we get some movement and a lot of strength

Front 23

how may joint capsules be reinforced?

Back 23

with accessory structures (tendons and ligaments); some fibers will be arranged as dense regular which are going to create the ligaments

Front 24

what is the joint capsule continuous with?

Back 24

the periosteum of each bone

Front 25

what creates ligaments?

Back 25

when fibers of the joint capsule are arranged as dense regular

Front 26

what are the four accessory structures in the knee?

Back 26

1. bursa (a pouch)
2. fat pads
3. meniscus (a crescent)
4. ligaments

Front 27

what is a bursa?

Back 27

-its a synovial membrane in the knee but is separated from the joint cavity; its the same thing as the joint cavity but its more superficial
-small pockets filled with synovial fluid
-reduce friction and act as shock absorbers

Front 28

where do bursas often form?

Back 28

in areas where tendon or ligament rubs against other tissues

Front 29

what is a bursas main function?

Back 29

reduces friction in the knee and acts as shock absorbers

Front 30

what are fat pads?

Back 30

they are localized masses of adipose tissue and the adipose tissue is covered by synovial membrane

Front 31

what are the fat pads two main functions?

Back 31

1. protect articular cartilages
2. act as packing material for joint (as joint relaxes, the fat fills in the area between the joints)

Front 32

what is the meniscus?

Back 32

a pad of fibrous cartilage between bones of synovial joint

Front 33

what is the function of the meniscus?

Back 33

it may subdivide joint cavity and affect fluid flow or allow variations in shapes of articular surfaces so it adds stability

Front 34

how does the meniscus affect fluid flow or allow variations in shapes of articular surfaces?

Back 34

because it can wrap around an area that is not shaped the same on both bones

Front 35

what do ligaments do?

Back 35

support, strengthen, and reinforce joint

Front 36

what are the two types of ligaments?

Back 36

intrinsic ligaments and extrinsic ligaments

Front 37

what is an intrinsic ligament?

Back 37

localized thickening of the joint capsule

Front 38

what is an extrinsic ligament?

Back 38

they separate from the joint capsule and may pass inside or outside the joint capsule

Front 39

what does intracapsular mean?

Back 39

when extrinsic ligaments pass inside the joint capsule

Front 40

what does extracapsular mean?

Back 40

when extrinsic ligaments pass outside the joint capsule