Arthrology 8

Question 1

How are joints classified functionally?

Answer 1

classified by the degree of movement permitted at the articulation

Question 2

What features are used to determine structural classification of joints?

Answer 2

a) the presence/absence of a joint cavity

b) the kind of connective tissue that binds the bones together

Question 3

What are the general classes of joints when structure is the determining factor?

Answer 3

1. fibrous
2. cartilaginous
3. synovial

Question 4

How is a fibrous joint classified functionally?

Answer 4

They are immovable (synarthroses).

Question 5

Does a fibrous joint have a joint cavity?

Answer 5

No.

Question 6

What is used to hold the articulating bones together in a fibrous joint?

Answer 6

Fibrous connective tissue.

Question 7

List the 3 main types of fibrous joints and give an example of each.

Answer 7

1. Sutural: sutures between the flat bones of the skull
2. Syndesmosis:
   a. white fibrous: interosseous membrane between r/u
   b. yellow fibrous: ligamentum flavum b/t lamina
3. Gomophosis: root of tooth with bone

Question 8

What are the two subgroups seen in the syndesmosis classification? Ex?

Answer 8

a. white fibrous: interosseous membrane between r/u

b. yellow fibrous: ligamentum flavum b/t lamina

Question 9

How is a cartilaginous joint classified functionally?

Answer 9

Generally considered slightly movable (amphiarthrotic).

Question 10

Does a cartilaginous joint have a joint cavity?

Answer 10

No.

Question 11

What is used to hold the articulating bones together in a cartilaginous joint?

Answer 11

Primary: hyaline cartilage
Secondary: hyaline and fibrocartilage

Question 12

What are the two main types of cartilaginous joints and how do they differ? Give an example of each.

Answer 12

Primary (synchondrosis) and secondary (symphysis) cartilaginous joints. The primary cartilaginous joint is typically temporary in nature (ie. epiphyseal plate/disc) and the secondary joint is permanent (intervertebral disc/pubic symphysis).

Question 13

How is a synovial joint classified functionally? Does it have a joint cavity?

Answer 13

Diarthrotic (freely moveable).

Yes.

Question 14

What is used to hold the articulating bones together in a synovial joint?

Answer 14

1. A connective tissue capsule, the collagen fibers of which blend with the periosteum of the articulating bones
2. ligaments (the collagen fibers of which also blend with the periosteum).

Question 15

Make sure you can label a diagram of a typical synovial joint indicating its major anatomical components.

Answer 15

Joint capsule blue
Synovial membrane red
Articular cartilage purple
Intra-articular disc

Question 16

What is a bursa and where might they be found?

Answer 16

A flattened sac lined by synovial membranes and filled with SF. They are located over certain diarthrotic joints and bony structures.

Question 17

What is a specific function of a bursa?

Answer 17

To provide cushion and to allow free movement of skin over bony pertuberance.

Question 18

What is bursitis and why is it clinically important?

Answer 18

Inflammation of the bursae. It is a clinically debilitating problem, limiting movement and activity.

Question 19

What might restrict movements at an articulation?

Answer 19

Apposition of softy body parts
tension of ligaments
muscle tension

Question 20

Be able to give an example of where the various types of movement might occur: 
Gliding
Angular
Rotation
Circumduction
Inversion/eversion
Dorsiflexion/plantarflexion
Protraction/retraction

Answer 20

Gliding: between carpal/tarsal bones
angular: elbow/knee joint
rotation: skull and C1
circumduction: upper limb at shoulder joint
inversion/eversion: foot
dorsiflexion/plantarflexion: foot
protraction/retraction: mandible
supination/pronation: forearm
elevation/depression: mandible

Question 21

How does structure reflect function with regard to movement at articulations? Give an example.

Answer 21

Shape of the articulating surfaces is the primary structural feature determining the degree of movement at any articulation. For example, flat surfaces (carpal bones) = limited movement, and concave/convex surfaces (knee joint) = free movement.

Question 22

Be able to list the 6 different types of synovial joints and give an example of each.

Answer 22

1. Gliding: carpal/tarsal bones
2. hinge: elbow/knee joint
3. pivot: proximal radius/ulna
4. ellipsoidal: radius and carpal bones
5. saddle: trapezium and metacarpal
6. ball and socket: shoulder/hip joints
   God has patience every Sunday brunch

Question 23

What axiom is exhibited throughout these subgroups of synovial joints? What’s the big idea here?

Answer 23

Shape of articulating surfaces determines variable number of degree of freedom (movement).