Cartilage

Question 1

What is cartilage?

Answer 1

Cartilage is a type of avascular connective tissue which forms part of the skeleton that needs more flexibility

Question 2

What is the function of cartilage?

Answer 2

Cartilage functions to support soft tissue, provide a smooth gliding surface for bone articulations at joints and enable the development and growth of long bones

Question 3

Cartilage is nourished by diffusion as it has no blood vessels, lymphatic vessels or nerves. T/F?

Answer 3

True

Question 4

What are the cells of the cartilage called?

Answer 4

Chondrocytes

Question 5

What is the function of cartilage cells?

Answer 5

To lay down a resilient, hydrated matrix of type II collagen and aggregates of glycosaminoglycans and proteoglycans.
They are responsible for the synthesis and turnover of cartilage

Question 6

What is the most important proteoglycan within cartilage and what does it do?

Answer 6

Aggrecan can rapidly bind to water molecules to assume a shape which occupies the maximum possible volume available so is particularly important in the function of cartilage as a shock absorber.

Question 7

What is the cartilage equivalent of the periosteum and what does it do?

Answer 7

The perichondrium is capable of laying down more cartilage and provides an attachment site for tendons and ligaments

Question 8

What are the three types of cartilage?

Answer 8

Hyaline
Elastic
Fibrocartilage

Question 9

What is the function and composition of hyaline cartilage?

Answer 9

Hyaline contains a moderate amount of collagen fibres with some elastic fibres and forms the temporary skeleton of the foetus, forms the epiphyseal plates of growing long bones, provides support to respiratory passages and covers the articular surfaces of joints.

Question 10

What is the composition and function of elastic collagen?

Answer 10

It contains a large number of elastic fibres with some collagen fibres and provides the shape of various structures such as the auricle of the ear.

Question 11

What is the composition and function of fibrocartilage?

Answer 11

Fibrocartilage contains many collagen fibres and provides high levels of strength and rigidity. It is a major constituent of the intervertebral discs, tendon attachment to bones and the junctions between flat bones of the pelvis.

Question 12

What is the composition of cartilage?

Answer 12

5% chondrocyte cells

95% ECM of which 70% is water and 30% is organic components

Question 13

What type of collagen is present in cartilage?

Answer 13

Type II

Question 14

There is a constant turnover of cartilage. How is degradation brought about?

Answer 14

Colagenases
Gelatinases
Stomelysins
Aggrecanases
Tissue inhibitors of metalloproteinases

Question 15

What affect do glucocorticoids and NSAIDs have on the degradation of cartilage?

Answer 15

They decrease the degradation of cartilage

Question 16

What affect does IGF and TGF beta have on cartilage synthesis?

Answer 16

Increases synthesis

Question 17

What affects do NSAIDs and cytokines have on cartilage synthesis?

Answer 17

Decrease synthesis

Question 18

Which cells carry out cartilage repair?

Answer 18

Chondrocytes

Question 19

Subchondral bone must be penetrated in order for cartilage to heal. T/F?

Answer 19

True

Question 20

When cartilage repair occurs, what type of cartilage is commonly laid down?

Answer 20

Fibrocartilage

Question 21

Which imaging modality is used to look for cartilage injuries?

Answer 21

MRI

Question 22

What are the no operative treatment options for cartilage injuries?

Answer 22

Physiotherapy - increase ROM, strengthen muscles

Analgesia - NSAIDs (not long term), paracetamol, glucosamine, chondroitin sulphate, steroid injection, steroid injection

Question 23

What are the operative treatment options for cartilage injuries?

Answer 23

Arthroscopy
Micro fracturing
Cartilage transplant
Joint replacement