Joints and their connective tissues

Question 1

what are joints?

Answer 1

where 2 bones meet and articulate

Question 2

structure of a joint allows?

Answer 2

mobility and overall stability

Question 3

the 2 classifications of joints are?

Answer 3

structural: can be fibrous, cartilaginous, synovial.
Functional: (focused on movement) can be synarthroses, amphiarthroses, diathroses

Question 4

what does synarthroses mean

Answer 4

immovable joints

Question 5

what does amphiarthroes mean

Answer 5

slightly movable joints

Question 6

what does diarthroses mean

Answer 6

freely movable joints

Question 7

describe fibrous joints. Give 3 examples

Answer 7

have dense regular CT, no cartilage. no joint cavity. it is fixed or scarcely movable. sutures, syndesmoses, gomphoses

Question 8

describe sutures

Answer 8

Mainly in the skull. The bones is coved by a layer of osteogenic cells called CAMBIAL, and covered by a fibrous tissue continuous with the periosteum called capsular lamella. there is a loose CT in between

Question 9

what are syndesmoses?

Answer 9

bones connected by only ligaments, whose movements depend on length of the fibers (its a fibrous connection)

Question 10

what are gomphoses?

Answer 10

ligament is a short periodontal ligament

Question 11

describe cartilaginous joints

Answer 11

the bone connection is made of cartilage, no joint cavity, slightly movable, there are 2 types (synchondrosis, symphysis)

Question 12

what is a Synchondroses?

Answer 12

is a cartilgenous joint made of non-articular hyaline cartilage. It tends to synostose with age

Question 13

give an example of synchondroses?

Answer 13

epiphyseal plates, and joint between first costal cartilage and manubrium

Question 14

what is a symphysis joint? Give 2 examples

Answer 14

the ends of the articulating bones are covered by hyaline cartilage but a disc of fibrocartilage connects the bones. Pubic symphysis and intervertebral discs

Question 15

describe synovial joints

Answer 15

the bones are not directly joined, there is a joint cavity, highly movable, there are 6 types: plane/gliding/hinge/pivot/condyloid/saddle/ball and socket

Question 16

what are 5 characteristics of synovial joints?

Answer 16

hyaline cartilage present, fibrous capsule present, synovial membrane present, fibrocartilagenous structures also present, joint stability is provided by ligaments and tendons

Question 17

what is the general structure of articular surfaces

Answer 17

have an irregular shape, covered by articular hyaline cartilage which can be permanent(deep coating) or transient(superficial coating near cavity)

Question 18

what is the general structure of a fibrous capsule?

Answer 18

it is attached to the whole circumference of the bone tip, it entirely surrounds the articulation. It is made of dense irregular CT. Can be intrinsic or extrinsic, inner surface is completely covered by synovial membrane

Question 19

function of articular cartilage?

Answer 19

to absorb shock and reduce friction during movement

Question 20

what is the general structure of a synovial membrane? (visually)

Answer 20

pink/smooth/small villi/secretes synovial fluid/dynamic changes in shape during movement/may protrude through capsule fibrous bundles forming bursae and tendon sheets

Question 21

name a few microscopic aspects of synovial membranes

Answer 21

has an intima (granular amorphous fiber-free matrix embedding packed synovial cells. Has subsynovial tissue (a fibrovascular layer, lamella of collagen and elastin, small fat lobules surrounded by highly vascularized septa, aspecific cell types)

Question 22

what is the general structure of fibrocartilagineous joints?

Answer 22

A fat pad, a disc or meniscus, labrum (additionally there is also tendons, accessory ligaments, bursae)

Question 23

what is a tendon sheath?

Answer 23

cylinders of CT lined with synovial membrane and wrapped around a tendon

Question 24

describe plane/gliding joints and give examples

Answer 24

are uniaxial, limited rotation is possible. Intervertebral, intercarpal

Question 25

describe saddle joints and give examples

Answer 25

are biaxial, thumb, intercarpal

Question 26

describe hinge joints

Answer 26

monoaxial, convex cylinder in one bone, corresponding concavity in other bone, elbow ankle interpharyngeal

Question 27

describe pivot joints

Answer 27

monoaxial, rotation around a single axis, cylindrical bone process rotating within a circle of bone and ligament, articulation between dens and atlas

Question 28

describe ball and socket joints

Answer 28

smooth hemispherical head fits within a cuplike depression, multiaxial, shoulder and hip joints

Question 29

describe condyloid joint

Answer 29

oval convex surface on one bone fits into a similarly shaped depression on other bone, atlantooccipital

Question 30

what are ligaments?

Answer 30

they hold joints together, guide movement, they can tear and cause the joint to dislocate

Question 31

what are ligaments made of?

Answer 31

dense CT which are sparcely vascularized, 20% fibroblasts, 80% extracellular cells– 70% water and 30% collagen, elastin