Structure and Function of Joints

Question 1

define synarthrosis:

Answer 1

immoveable joint

Question 2

Define amphiarthrosis

Answer 2

joint allowing slight movement, like spine

Question 3

Define diarthrosis

Answer 3

joints allowing for free movement, our MAIN focus of the lectures

Question 4

Synchondrosis means almost _____ joint between bones bound by layer of _____ ex: ____

Answer 4

immoveable; cartilage; ribs

Question 5

What is the capsule around joints made out of?

Answer 5

Collagen connective tissues and is comprised of articular capsule which is overflow of periosteum from bone, fibrous outer layer aka capsular layer, and synovial inner layer

Question 6

Which part of the joint capsule is the most vascular. It also has nerve endings, absorbs/secretes synovial fluids and is responsible for nutrient exchange between blood and joint

Answer 6

Synovial layer (inner)- secretes synovial fluids and surrounds tendons passing through the joint cavity

Question 7

Synovial fluids are made up of what 4 components?

Answer 7

HA, lubricin, proteinases, collagenases

Question 8

Where does synovial fluids come from?

Answer 8

Plasma of cells within the jt

Question 9

Synovial fluid is sterile and composed of Vascular connective tissues ___ and ___

Answer 9

A and B

Question 10

Vascular connective tissue A

Answer 10

blood monocyte in origin and removes wear and tear debris

Question 11

Vascular connective tissue B

Answer 11

produces hyaluronan

Question 12

What two things are desirable to reduce tissue stress?

Answer 12

Cartilage deformation and increased joint conformity

Question 13

What are the cartilage zones?

Answer 13

Superficial Zone: high water, low proteoglycan conc., soft

Intermediate Zone: thickest part, slightly elastic, high proteoglycan conc. But low water and collagen

Deep zone: Lowest conc. Of water, highest conc. Of proteoglycans, transfers load to subchondral bone

Zone of Calcified cartilage: contacts the bone, deepest layer, tidemark is the barrier between subchondral bone and articular cartilage (no nutrient transfer here)

Question 14

___ connect bone and tissue to tissue

Answer 14

ligaments

Question 15

fibrous cords of CT of collagen, elastic fibers and fibrocytes=

Answer 15

ligament- poorly vascular and acellular, makes primary healing of tears difficult, gets nutrition from synovial fluid like tendons do, has roles in proprioception.

Question 16

Muscle to bone =

Answer 16

tendons

Question 17

Mostly type 1 collagen, not very vascular, stabilize jt and absorb shock, get nutrition from synovial fluids and heal slowly

Answer 17

tendons

Question 18

What is the term for when pressure causes a barrier against cells migrating into or out of the joint space via hyaluronan in the fluid?

Answer 18

Molecular seiving

Question 19

____ cells predominate in synovial fluid

Answer 19

mononuclear cells

Question 20

Collagen makes up how much of the total cartilage mass? Proteoglycans make up how much of the cartilage?

Answer 20

Collagen makes up 10-20% and proteoglycans make up 15%

Question 21

Chondrocytes produce what three things?

Answer 21

Collagen, proteoglycans, and enzymes

Question 22

Components of the ECM that trap and hold water are ______ and ______

Answer 22

proteoglycans and glycosaminoglycans

Question 23

What is the most common proteoglycan ?

Answer 23

Aggrecan