Joint classification

Question 1

3 major types of joints (structural), 3 major types of joints (function)

Answer 1

Structure
1. FIBROUS
- sutures
- syndesmosis
- gomphoses
2. CARTILAGENOUS
- synchondrosis
- symphysis
3. SYNOVIAL

Function
1. Synarthrosis (no movement)
2. Amphiarthrosis (slight movement)
3. Diarthrosis (free movement)

Question 2

fibrous joints

Answer 2

• bones united by fibrous connective tissue
• no join cavity
• no movement

3 types
1. SUTURES
- dense regular collagenous CT
- no movement
- e.g. skull sutures
2. SYNDESMOSIS
- bones further apart
- joined by ligaments
- dense regular collagenous CT
- some movement
- e.g. between radius and ulna
3.GOMPHOSES
- peg and socket
- bundles of regular collagenous CT
- e.g. teeth

Question 3

what connects frontal and parietal bones?

Answer 3

coronal suture

Question 4

what connects parietal bones

Answer 4

sagittal suture

Question 5

what connects parietal bones to occipital bone

Answer 5

lambdoid suture

Question 6

fontanels

Answer 6

membranous spaces between cranial bones when young, allow for movement
- anterior, posterior and lateral sides

Question 7

catilagenous joints

Answer 7

bones united by hyaline cartilage or fibrocartilage

2 types
1. SYNCHRONDROSIS
- joined by hyaline cartilage
- no movement
- e.g. bones around epiphyseal plate before ossification
2. SYMPHYSIS
- united via fibrocartilage
- somewhat flexible
- e.g. pubis symphysis, between vertebral bodies

Question 8

wide area between sutures in a newborn is called

Answer 8

fontanels

Question 9

what makes up the joint (articular) capsule of a synovial joint?

Answer 9

fibrous membrane (outside) and synovial membrane (inside) create join cavity filled with synovial fluid

Question 10

synovial joints

Answer 10

• contain synovial fluid (hyaluronic acid = slippery)
• articular cartilage
• freely moveable
• joint cavity made of fibrous membrane (outside) and synovial membrane (inside)

Question 11

where do synovial joints get nutrients?

Answer 11

• diffuse through synovial membrane (blood vessels can’t get through)
• synovial fluid
• spongy bone

Question 12

purpose of nerve in synovial joints

Answer 12

not to detect pain!
gives info about position of joint

Question 13

bursae

Answer 13

found at many synovial joints
sac-like structures filled with synovial fluid that cushion movement (reduce friction)

Question 14

tendon sheaths

Answer 14

found at many synovial joints
tube-like sacs that wrap around tendons exposed to a lot of friction

Question 15

menisci

Answer 15

crescent shaped pads of fibrocartilage found within joint capsule between the bones
e.g. knee and wrist joints

Question 16

6 types of synovial joints

Answer 16

classified according to shape of the articular surface
1. plane
2. hinge
3. pivot
4. ellipsoid (condyloid)
5. saddle
6. ball and socket

Question 17

3 types of movement at synovial joints

Answer 17

1. uniaxial (mono)
2. biaxial
3. multiaxial (triaxial)

Question 18

plane joint

Answer 18

gliding joint
- 2 flat surfaces
- uniaxial
- held by ligaments
- e.g. intervertebral joint, intertarsal/intercarpal joints

Question 19

2 types of joints in vertebrae

Answer 19

symphysis joint (@ disk) and plane joint (intervertebral)

Question 20

hinge joint

Answer 20

• uniaxial
• e.g. elbow (trochlea and troclear notch), ankle, knee, interphalangeal

Question 21

pivot joint

Answer 21

• uniaxial (only rotates around single axis)
• e.g. head of radius against ulna (ANNULAR LIGAMENT wraps around to facilitate pro/supination), dens

Question 22

ellipsoid

Answer 22

• biaxial, no rotation
• oval concave surface articulates with oval convex
• atlanto-occipital joint, knuckles, radius with wrist bones

Question 23

saddle joints

Answer 23

• biaxial
• e.g. thumb joint

Question 24

ball and socket joint

Answer 24

• multi axial

Question 25

synovial fluid secreted by

Answer 25

synovial membrane