Lecture 18 - Articular System and Joints

Question 1

Name the 3 types of cartilage found in the body and give an example of where each type of cartilage can be found

Answer 1

a. Hyaline – most common type, covers bony articular surfaces e.g.
b. Elastic – flexible, forms discrete structures in external ear, auditory tube, parks of larynx
c. Fibrocartilage – forms specialised in joints (e.g. discs, meniscus, labrum)

Question 2

Describe the structure and function of fibrous and cartilaginous joints

Answer 2

a. Fibrous joints
i. Solid, minimal movement
ii. Bones united y fibrous tissue; degree of movement depends on length of fibres
b. Cartilaginous
i. Solid, minimal movement
ii. Bones united by hyaline or fibrocartilage
iii. Provide strength and shock absorption

Question 3

Describe the general features of a synovial joint including accessory structures

Answer 3

a. Moveable
b. Bones united by a joint/articular cavity; many associated structures
c. Associated structures
i. Articular discs
ii. Menisci
iii. Labrum
iv. Fat pads
v. Bursae
vi. Tendon sheaths

Question 4

plane joint

Answer 4

Allows sliding or gliding movement when one bone moves across the surface of another
e.g. – intercarpal joints, joints between vertebral articular surfaces

Question 5

hinge joint

Answer 5

Allow movement at right angles to the joint, produces flexion/extension
e.g. elbow joints, interphalangeal joints

Question 6

pivot joint

Answer 6

Allows movement in line with the longitudinal axis of the bones, produces rotation
e.g. proximal radioulnar joint, atlantoaxial joint

Question 7

condylar joint

Answer 7

Allows movement around two axes at right angles, produces flexion, extension, adduction and abduction
e.g. metacarpophalangeal (knuckle) joints, wrist joints

Question 8

saddle joint

Answer 8

Allows movement around two axes at right angles, bones are saddle shaped, produce flexion, extension, adduction and abduction
e.g. carpometacarpal joints of the thumb

Question 9

ball and socket

Answer 9

Allow movement around multiple axes, bones are shaped like ball and socket, produce flexion, extension, adduction, abduction, circumduction and rotation
e.g. shoulder and hip joints

Question 10

what are the factors that affect joint mobility and stability?

Answer 10

a. Structure/shape of articulating bones
b. Strength and tension of joint ligaments
c. Arrangement and tension of muscles
d. Contact of soft parts
e. Hormones
f. disuse