4. Articulations/Joints

Question 1

What is a joint?

Answer 1

Place of contact between two or more bones (articulation)

Some joints are very mobile, others immobile

Question 2

Mobility/stability relationship of joints

Answer 2

More planes or motion = reduced stability

Question 3

How is joint stability increased?

Answer 3

Muscular support and ligamentous attachment

Question 4

How are joints classified

Answer 4

By structure or function

Question 5

Structural classifications of joints

Answer 5

Fibrous, cartilaginous, and synovial

Question 6

Joint that connects bones connected and made of dense regular connective tissue

Answer 6

Fibrous joint

Question 7

Joint that connects bones by plates of cartilage

Answer 7

Cartilaginous joint

Question 8

Articular capsule with joint cavity

Answer 8

Synovial joint

Question 9

Types of fibrous joints

Answer 9

Gomphosis, sutures, and syndesmosis

Question 10

Characteristics and example of gomphosis

Answer 10

Immobile and consist of small amounts of dense connective tissue

Ex) teeth and sockets

Question 11

Characteristics and example of sutures

Answer 11

Immobile and consist of small amount of dense connective tissue with irregular edges

Ex) skull bones

Question 12

What does irregular edges do for sutures

Answer 12

Increases surface area, which increases stability

Question 13

Characteristics and example of syndesmosis

Answer 13

Slightly mobile and consists of large amounts of dense regular connective tissues

Ex) interosseous membrane of tibia-fibula and radius-ulna

Question 14

Types of cartilaginous joints

Answer 14

Synchondrosis and symphysis

Question 15

Characteristics and example of synchondrosis

Answer 15

Immobile and connected by hyaline cartilage

Ex) 1st rib-manubrium, epiphyseal plates

Question 16

Characteristics and example of symphysis

Answer 16

Slightly mobile and connected by fibrocartilage

Ex) intervertebral discs, pubic symphysis

Question 17

Types of synovial joints

Answer 17

Planar, hinge, pivot, saddle, condylar, and ball-socket

Question 18

Characteristics of synovial joints

Answer 18

Very mobile, consists of articular capsule with joint cavity, lined by articular/hyaline cartilage, and stable due to ligaments/muscles

Question 19

Components of articular capsule of synovial joints

Answer 19

Fibrous capsule for support

Synovial membrane that lines joint cavity and secretes synovial fluid

Question 20

Joint movement that decreases angle

Answer 20

Flexion

Question 21

Joint movement that increases angle

Answer 21

Extension

Question 22

Joint movement away from midline

Answer 22

Abduction

Question 23

Joint movement toward midline

Answer 23

Adduction

Question 24

Joint movement rotating outward

Answer 24

Lateral rotation

Question 25

Joint movement rotating inward

Answer 25

Medial rotation

Question 26

Joint movement superiorly

Answer 26

Elevation

Question 27

Joint movement inferiorly

Answer 27

Depression

Question 28

Joint movement forward

Answer 28

Protraction

Question 29

Joint movement backward

Answer 29

Retraction

Question 30

Joint movement where palm is rotated anteriorly

Answer 30

Supination

Question 31

Joint movement where palm is rotated posteriorly

Answer 31

Pronation

Question 32

Joint movement of sole of foot inward

Answer 32

Inversion

Question 33

Joint movement of sole of foot outward

Answer 33

Eversion

Question 34

Joint movement of elevating foot

Answer 34

Dorsiflexion

Question 35

Joint movement of depressing foot

Answer 35

Plantar flexion

Question 36

Types of movement at synovial joints

Answer 36

Nonaxial, uniaxial, biaxial, multiaxial

Question 37

Movement in which bones slide across each other on plane (not around an axis)

Answer 37

Nonaxial movement

Question 38

Movement around one axis

Answer 38

Uniaxial movement

Question 39

Movement around 2 axes/planes Ex) front to back and side to side

Answer 39

Biaxial movement

Question 40

Movement around all three axes/planes Ex) front to back, side to side, rotation/twisting

Answer 40

Multiaxial movement

Question 41

Flat articular surface that undergoes nonaxial movement via gliding

Answer 41

Plane joint

Question 42

Examples of plane joints

Answer 42

Intercarpal joints, intertarsal joints, and joints between vertebral articular surfaces

Question 43

Joint consisting of a cylinder and trough that undergoes uniaxial movement via flexion and extension

Answer 43

Hinge joint

Question 44

Examples of hinge joints

Answer 44

Elbow joints and interphalangeal joints

Question 45

Joint consisting of a sleeve and axle that undergoes uniaxial movement via rotation

Answer 45

Pivot joint

Question 46

Examples of pivot joints

Answer 46

Proximal radioulnar joints, atlantoaxial joint

Question 47

Joint consisting of oval articular surfaces that undergoes biaxial movement via flexion/extension and adduction/abduction

Answer 47

Condylar joint

Question 48

Examples of condylar joints

Answer 48

Metacarpophalangeal (knuckle) joints, wrist joints

Question 49

Joint consisting of articular surfaces that are both concave and convex and undergoes biaxial movement via adduction/abduction and flexion/extension

Answer 49

Saddle joint

Question 50

Examples of saddle joints

Answer 50

Carpometacarpal joints of the thumbs

Question 51

Joint consisting of a cup (socket) and spherical head (ball) that undergoes multiaxial movement via flexion/extension, adduction/abduction, and rotation

Answer 51

Ball-and-socket joint

Question 52

Examples of ball-and-socket joints

Answer 52

Shoulder joints and hip joints