Chapter 8 joints

Question 1

joints

Answer 1

the junction of two or more bones

Question 2

synarthosis

Answer 2

immovable joint

Question 3

amphiarthorsis

Answer 3

a slightly movable joint

Question 4

diarthrosis

Answer 4

freely movable joint

Question 5

fibrous joints

Answer 5

bones joined by fibrous tissue; no joint cavity is present

Question 6

suture

Answer 6

an immovable fibrous joint; with one exception, all the bones of the skull are united by sutures

Question 7

synostoses

Answer 7

a completely ossified joint; a fused joint

Question 8

syndesmosis

Answer 8

a fibrous joint in which the bones are united by a ligament or a sheet of fibrous tissue

Question 9

gomphosis

Answer 9

a fibrous joint; peg-in-socket fibrous joint, ex. tooth with bony alveolar socket.

Question 10

cartilaginous joints

Answer 10

bones united by cartilage; no joint cavity

Question 11

synchondrosis

Answer 11

a cartilaginous joint in which the bones are united by hyaline cartilage; almost all are synarthrotic (immovable)
ex. epiphyseal plates in children

Question 12

symphysis

Answer 12

a cartilaginous joint in which the bones are connected by fibrocartilage.

Question 13

plane joint

Answer 13

flat articular surfaces, nonaxial movement, gliding, found in intercarpal joints

Question 14

hinge joint

Answer 14

cylinder & trough; uniaxial movement, flexion and extension (medial/lateral axis) found in elbow joints

Question 15

pivot joints

Answer 15

sleeve(bone and ligament) & axle; uniaxial movement (vertical axis) rotation; proximal radioulnar joints

Question 16

condylar joint

Answer 16

oval articular surfaces, biaxial movement, medial/lateral axis, flexion and extension, adduction and abduction; wrist joints

Question 17

saddle joint

Answer 17

articular surfaces are both concave and convex; biaxial movement, medial/lateral axis, anterior/posterior axis; adduction and abduction; flexion and extension; carpometacarpal joints of the thumbs

Question 18

ball-and-socket joint

Answer 18

cup(socket) and spherical head (ball); multiaxial movement, medial/lateral axis, flexion and extension; anterior/posterior axis, adduction and abduction; and vertical axis, rotation, shoulder joints,

Question 19

synovial joint

Answer 19

freely movable joint exhibiting a joint cavity; also called a diarthrosis

Question 20

6 synovial joint features

Answer 20

articular cartilage, joint cavity, articular capsule, synovial fluid, reinforcing ligaments, nerves and blood vessels

Question 21

articular cartilage

Answer 21

hyaline cartilage covering bone ends at movable joints

Question 22

joint (articular cavity)

Answer 22

potential space that contains a small amount of synovial fluid

Question 23

articular capsule

Answer 23

double-layered capsule composed of an outer fibrous layer lined by synovial membrane; encloses the joint cavity of a synovial joint.

Question 24

synovial membrane’s function

Answer 24

make synovial fluid

Question 25

synovial fluid

Answer 25

fluid secreted by the synovial membrane; lubricates joint surfaces and nourishes articular cartilages.

Question 26

reinforcing ligaments

Answer 26

synovial joints are reinforced and strengthened by a number of band-like ligaments.

Question 27

weeping lubrication

Answer 27

a form of hydrostatic lubrication in which the interstitial fluid of hydrated articular cartilage flows into its surface when a load is applied.

Question 28

capsular ligaments

Answer 28

thickened fibrous structures, lined with synovial membrane and surrounding articulations.

Question 29

intrascapsular ligaments

Answer 29

ligaments located within and separate from the articular capsule of a synovial joint.

Question 30

fatty pads

Answer 30

cushioning between fibrous layers and synovial membrane or bone.

Question 31

menisci (articular discs)

Answer 31

discs or wedges of fibrocartilage separating articular surfaces

Question 32

bursa

Answer 32

a fibrous sac lined with synovial membrane and containing synovial fluid; occurs between bones and muscle tendons (or other structures) where it acts to decrease friction during movement

Question 33

tendon sheath

Answer 33

an elongated bursa that wraps completely around a tendon subjected to friction

Question 34

factors influencing the stability of synovial joints

Answer 34

1. the shapes of the articular surfaces 2. the number & position of ligaments 3. muscle tone (for many, this is most important)

Question 35

muscle tone

Answer 35

low levels of contractile activity in relaxed muscles that keep the muscles healthy and ready to react to stimulation

Question 36

origin

Answer 36

attachment of a muscle that remains relatively fixed during muscular contraction (one end)

Question 37

insertion

Answer 37

(other end) movable attachment of a muscle

Question 38

body movement happens when

Answer 38

muscles contract across joints and their insertion moves towards their origin.

Question 39

nonaxial movement

Answer 39

slipping movements only

Question 40

uniaxial movement

Answer 40

movement in one plane

Question 41

biaxial movement

Answer 41

movement in two planes

Question 42

multiaxial movement

Answer 42

movement in or around all three planes of space & axes.

Question 43

3 general types of movement

Answer 43

gliding, angular movements and rotation

Question 44

gliding

Answer 44

occurs when one flat or nearly flat, bone surfaces glides or slips over another without appreciable angle and rotation

Question 45

angular movements

Answer 45

increase or decrease the angle between two bones

Question 46

flexion

Answer 46

movement that decreases the angle of the joint, ex. bending the knee from a straight to an angled position,

Question 47

extension

Answer 47

is the reverse of flexion and occurs at the same joints. increases the angle of the joints.

Question 48

hyperextension

Answer 48

movements beyond the anatomical position.

Question 49

abduction

Answer 49

to move away from the midline of the body

Question 50

adduction

Answer 50

moving toward, movement of a limb toward the body midline

Question 51

circumduction

Answer 51

circular movement of a body part so that it outlines a cone in space.

Question 52

rotation

Answer 52

the turning of a bone around its own long axis.

Question 53

pronation

Answer 53

(palm down) radius rotates over ulna, inward rotation of the forearm causing the radius to cross diagonally over the ulna-palms face posteriorly.

Question 54

supination

Answer 54

(palm up) radius and ulna are parallel, outward rotatiuon of forearm causing palms to face anteriorly

Question 55

doriflexion

Answer 55

pointing foot up

Question 56

plantar flexion

Answer 56

pointing foot down

Question 57

inversion

Answer 57

sole towards midline

Question 58

eversion

Answer 58

sole towards lateral

Question 59

protraction

Answer 59

nonangular anterior movement in a transverse plane

Question 60

retraction

Answer 60

nonangular posterior movement in a transverse plane (mandible)

Question 61

elevation

Answer 61

lifting a body part superiorly, ex. shrugging shoulders

Question 62

depression

Answer 62

moving the elevated part inferiorly

Question 63

opposition

Answer 63

of the thumbs, is the action taken when you touch your thumb to the tips of the other fingers on the same hand