Osteoarthritis

Question 1

What is osteoarthritis?

Answer 1

Chronic, progressive failure of articular cartilage

Question 2

Which joints are typically affected in osteoarthritis?

Answer 2

Hand (esp pinch grip)
-DIP
-PIP
-First CMC
Spine
Hips 
Knees (weight bearing joints)
Lower limb
-First MTP

Question 3

What do you call the growth of new bone at joints?

Answer 3

Osteophytes

Question 4

What do you call osteophytes at DIP?

Answer 4

Heberden’s nodes

Question 5

What do you call osteophytes at PIP?

Answer 5

Bouchard’s nodes

Question 6

Describe the symptoms of osteoarthritis

Answer 6

Joint pain worse with activity, better at rest

Joint stiffness after immobility e.g. in the morning

Question 7

What signs can be associated with osteoarthritis?

Answer 7

Joint crepitus (creaking)
Joint instability
Joint enlargement (nodes)
Limitation of motion

Question 8

Which phenomenon describes stiffness after immobility?

Answer 8

Gel phenomenon (gelling)

Question 9

Describe the radiographic features of osteoarthritis

Answer 9

Narrowing of joint space
Hardening of bone under cartilage (subchondral bony sclerosis)
Osteophytes
Subchondral cysts (fluid filled sacks under cartilage)

Question 10

List two things you see in rheumatoid arthritis, which would not be seen in osteoarthritis

Answer 10

Osteopenia

Bony erosions

Question 11

List two things seen in osteoarthritis but not in rheumatoid arthritis

Answer 11

Subchondral sclerosis

Osteophytes

Question 12

List a radiographic change seen in both rheumatoid arthritis and osteoarthritis and explain the difference

Answer 12

Joint space narrowing
In RA this is a secondary damage due to synovitis
In osteoarthritis it is a primary abnormality

Question 13

Why does osteoarthritis develop?

Answer 13

Excessive loading on joints

Abnormal joint components

Question 14

Describe the cartilage changes seen in osteoarthritis

Answer 14

Reduced proteoglycan
Reduced collagen
Chondrocyte changes e.g. apoptosis

Question 15

Describe the composition of articular cartilage

Answer 15

Type 2 collagen
Chondrocytes
Proteoglycan monomers

Question 16

Give an example of intracellular proteoglycan

Answer 16

Serglycin

Question 17

Give an example of cell-surface associated proteoglycan

Answer 17

Betablcan

Syndecan

Question 18

Give five examples of proteoglycan secreted into ECM

Answer 18

Aggrecan
Decorin
Fibromodulin
Lumican
Biglycan

Question 19

What are GAGs?

Answer 19

Glycosaminoglycans i.e. repeating polymers of disaccharides

Question 20

Give five examples of GAGs

Answer 20

Chondroitin sulphate 
Heparan sulphate
Keratan sulphate
Dermatan sulphate
Heparin

Question 21

What is the major proteoglycan in articular cartilage?

Answer 21

Aggrecan

Question 22

What is the ONLY non-sulphated GAG?

Answer 22

Hyaluronic acid

Question 23

What is the role of hyaluronic acid?

Answer 23

Maintains synovial fluid viscosity

Question 24

How do the chemical properties of GAG enable their weight-bearing properties?

Answer 24

Negatively charged GAG attracts water, therefore can expand and shrink as load is placed onto the cartilage

Question 25

What are the monomers in the following GAG: chondroitin sulphate

Answer 25

Glucoronic acid | N acetyl galactosamine

Question 26

What are the monomers in the following GAG: keratan sulphate

Answer 26

Galactose | N acetyl galactosamine

Question 27

What are the monomers in the following GAG: hyaluronic acid

Answer 27

Glucoronic acid | N acetyl galactosamine

Question 28

How do you manage osteoarthritis?

Answer 28

Education Physical therapy (physiotherapy, hydrotherapy) Occupational therapy Weight loss where appropriate Exercise Analgesia (paracetamol, NSAIDs, intra-articular corticosteroid injection) Joint replacement

Question 29

What other approaches to osteoarthritis exist, but are NOT approved of in the UK?

Answer 29

Glucosamine and chondroitin sulphate supplements | Intra articular injections of hyaluronic acid

Question 30

What could future therapies for osteoarthritis look like?

Answer 30

Aggrecanase inhibitors Cytokine inhibitors Stimulate the repair of matrix/stop matrix breakdown

Question 31

What type of collagen is in the synovium and in the articular cartilage?

Answer 31

Synovium - Type 1 | Articular cartilage - Type 2

Question 32

Which joints are commonly spared in osteoarthritis?

Answer 32

``` MCP Wrist Elbow Shoulder Ankle Tarsal joints ```