Joints

Question 1

Joint definition

Answer 1

Union between two or more rigid components (bone or cartilage) - can allow for articulation

Question 2

What are joints needed for?

Answer 2

Growth + movement

Question 3

Types of Joints

Answer 3

1. Fibrous
2. Cartilaginous
3. Synovial

Question 4

Fibrous joints (structure and properties)

Answer 4

Dense fibrous CT
Have high tensile strength with little movement in adults

Question 5

3 Types oif fibrous joint

Answer 5

• Sutures - skull (cranial sutures)
• Gomphoses - immobile joints between the teeth and their sockets in the mandible and maxillae (periodontal ligament)
• Syndesmoses -slightly movable joints (amphiarthroses) - 2 parrellel bones joined (e.g. tibia and fibula - interosseus membranes)

Question 6

Explain cartilaginous joints

Answer 6

Attached by cartilage (fibrous or hyaline)

Question 7

What are the two types of cartilaginous joint called

Answer 7

• Synchondroses (primary)
• Symphyses (secondary)

Question 8

Synchrondroses properties

Answer 8

No movement and dissapear in adults. Uses hyaline cartilage

Question 9

What is the purpose of synchrondroses

Answer 9

Allow for bone growth - endochondral ossification

Question 10

Symphyses

Answer 10

Don’t ossify with age, found in the midline of the body and have limited movement - ex inc. pubic symphysis, intervertebral discs

Question 11

Properties of synovial joints

Answer 11

• greatest movement
• 6 Types

Question 12

Parts of synovial joints

Answer 12

Synovial fluid, synovial (joint) cavity - other joints don’t have, fibrous capsule, synovial membrane, articular cartilage

Question 13

What cartilage is found in synovial joints

Answer 13

Articular (hyaline) cartilage

Question 14

What does the synovial membrane do?

Answer 14

Produce synovial fluid

Question 15

What may synovial joints also contain

Answer 15

• Articular discs
  *Ligaments

Question 16

6 Types of synovial joint + example

Answer 16

• Hinge - elbow
• Pivot - between (C1 and C2) vertebrae
• Saddle - finger (trapezium carpal and 1st metacarpal bone)
• Condylar (ellipsoid) - radius and carpal bone of wrist
• Plane - between tarsal bones (ankle)
• Ball and socket - hip/shoulder joint

Question 17

Joint stability

Answer 17

Joints need support - ligaments (/fibrous caspsules = protection) do this however, the tighter a ligament is (more stable), the less motion the joint has.

Question 18

Why is flexation at elbow and knee in opposite directions?

Answer 18

Upper limb - lateral rotation in womb
Lower limb - medial rotaion (and more rotation)

Question 19

briefly describe blood and nerve supply to joints

Answer 19

Joints have a rich blood and nerve supply (proprioception - where joint is). Anastomoses are common around joints. Hilton’s law is that the nerve supplying a muscle that crosses a certain joint will also innervate this joint.

Question 20

What are symphyses made of

Answer 20

hyaline cartilage

Question 21

Synchrondroses (primary/secondary and why)

Answer 21

Primary (like in kids) so endochondral ossification and gone in adults