Joints

Question 1

what is another name for joint?

Answer 1

articulations

Question 2

site where two or more bones meet

Answer 2

joint

Question 3

function of a joint

Answer 3

1. gives skeleton mobility
2. holds skeleton together

Question 4

structural classifications of a joint (based on type of material binded to joint)

Answer 4

1. fibrous
2. cartilaginous
3. synovial (cavity)

Question 5

functional classification of a joint, (based on the movement the joint allows)

Answer 5

1. synarthrosis
2. amphiarthrosis
3. diarthrosis

Question 6

synarthrosis

Answer 6

immovable, ex: skull

Question 7

amphiarthrosis

Answer 7

slightly movable, ex: pubic symphysis, and vertebrae

Question 8

diarthrosis

Answer 8

freely movable, ex: knees, ankles, fingers, etc.

Question 9

Three types of fiberous joints

Answer 9

sutures
syndesmoses
gomphoses

Question 10

sutures

Answer 10

joints of the skull, protect the brain

Question 11

syndesmoses

Answer 11

-Bones connected by ligaments, bands of fibrous tissue
-Short fibers offer little to no movement
-Ex: inferior tibiofibular joint
-Long fibers offer a larger amount of movement
-Ex: interosseous membrane connecting radius and ulna

Question 12

Gomphoses

Answer 12

Peg-in-socket joints
Ex: teeth
Held in by periodontal ligament

Question 13

Cartilaginous joints

Answer 13

-United by cartilage
-No joint cavity
-Not highly movable
-Synchondroses - bar or plate of hyaline cartilage unites bones
-Ex: cartilage of 1st rib with manubrium of sternum
-Sympheses - joined by hyaline and articular cartilage
-Are slightly movable
-Ex: intervertebral joints, pubic symphysis

Question 14

Synovial joints

Answer 14

All have fluid filled joint cavity
All are diarthrotic, freely movable
All share 6 characteristics

Question 15

6 characteristics of synovial joints

Answer 15

1. Articular cartilage
   - Consists of hyaline cartilage
   - Prevents crushing of bone ends
2. Joint (synovial) cavity
3. Articular joint capsule
   - Fibrous layer → external
   - Inner synovial membrane → internal
4. Synovial fluid
   - Lubricates and nourishes cartilage
   - Phagocytic cells
5. Reinforcing ligaments
   - Capsular - thickened part of fibrous layer
   - Extracapsular - outside the capsule
   - Intracapsular - deep to capsule; covered by synovial membrane
6. Nerves and blood vessels
   - Nerves detect pain; monitor joint position and stretch
   - Blood vessels supply filtrate for synovial fluid

Question 16

Other features of synovial joints

Answer 16

-Fatty ads for cushioning
-Discs - menisci
Made of fibrocartilage
Improve fit
Stabilize joint
Reduce wear and tear
-Bursae
Bags filled with synovial fluid “ball bearing”
Reduce friction where ligaments, tendons, muscles, skin, and bones rub together
-Tendon sheaths
Bursae that wrap around tendons

Question 17

Joint stability

Answer 17

-Shape of articular surface
Minor role
Shallow are less stable than ball-and-socket
-Ligament number and location
More ligaments = more strong joint
-Muscle tone
Most important for reinforcing knee and shoulder

Question 18

Movements

Answer 18

-All muscles attach bones or connective tissue at no fewer than two points
-Origin - attachment to immovable bone
-Insertion - attachment to moveable bone

Question 19

Gliding

Answer 19

princess wave

Question 20

Flexion

Answer 20

Angle smaller

Question 21

extension

Answer 21

angle bigger

Question 22

hyperextension

Answer 22

Angle beyond normal position

Question 23

abduction

Answer 23

Take away from body

Question 24

adduction

Answer 24

bring to (add) body

Question 25

Circumduction

Answer 25

circle movement

Question 26

Medial rotation

Answer 26

Turn head/foot to middle from side

Question 27

lateral rotation

Answer 27

Turn head/foot to side from middle

Question 28

supination

Answer 28

Bowl of soup → palm up

Question 29

pronation

Answer 29

No soup → palm down

Question 30

Dorsiflexion FOOT ONLY

Answer 30

toes to ceiling

Question 31

Plantar flexion FOOT ONLY

Answer 31

toes to floor

Question 32

Inversion

Answer 32

inward twist

Question 33

eversion

Answer 33

outward twist

Question 34

protraction JAW

Answer 34

stick out chin

Question 35

retraction JAW

Answer 35

pull chin back in

Question 36

elevation JAW AND SHOULDER

Answer 36

lifting

Question 37

depression JAW AND SHOULDER

Answer 37

dropping

Question 38

synovial joint types

Answer 38

-Plane → carpals -Hinge → elbow -Pivot → between radius and ulna → --allows us to flip board -Condylar → between phalanges and -metacarpals → biaxial -Saddle → thumbs -Ball-and-socket → shoulder and hips