Discuss the basic epidemiology, pathophysiology, presentation, investigation, management and prognosis of osteoarthritis

Question 1

What is the pathophysiology behind cysts and sclerosis in OA?

Answer 1

cysts and new bone is laid down (sclerosis) as a result of microfracturing of the articular surface

Question 2

What developmental abnormalities predispose to 2º OA?

Answer 2

• developmental dysplasia of the hip
• slipped femoral epiphysis

Question 3

What are heberden’s nodes?

Answer 3

Small bony growths that appear on the DIP joints

Question 4

What is the pathophysiology behind osteophytes?

Answer 4

osteophytes are caused by disorganised new bone formation at the joint margins

Question 5

When is osteoarthritis described as primary?

Answer 5

when no single underlying cause is identified

Question 6

What can you see on this image?

Answer 6

herbeden’s nodes

bouchard’s nodes

Question 7

What is osteoarthritis?

Answer 7

osteoarthritis is a disorder of synovial joints characterised by articular surface damage, formation of new bone and secondary inflammation

Question 8

What are the four cardinal features found on X ray examination of osteoarthritis joints?

Answer 8

1. joint space narrowing
2. sclerosis
3. cyst formation
4. osteophytes

Question 9

How does osteoarthritis typically present?

Answer 9

• Pain worse on movement
• Pain worse at the end of the day
• Morning stiffness <30 minutes
• Joint instability

Question 10

What are 6 risk factors for 1º OA?

Answer 10

1. increasing age
2. female gender
3. occupation
4. muscle weakness
5. obesity
6. inflammatory joint disease

Question 11

What are Bouchard’s nodes?

Answer 11

Bony growths on the PIP joints

Question 12

What is the joint pattern of OA?

Answer 12

• joints are usually affected in an asymmetrical pattern
• single or multiple joints involved
• most commonly the knees, hips and hands
• within the hands: 1st carpometacarpal joint, DIPs, PIPs
• wrists, shoulders and elbows are also susceptible

Question 13

Histologically, what causes osteoarthritis?

Answer 13

• repeated microtrauma or abnormal biomechanical forces cause damage to the weight-bearing cartilage surface
• which eventually wears away completely exposing the subchondral bone
• chondrocytes attempt repair by releasing degradative enzymes

Question 14

What hormonal abnormality predisposes a patient to OA?

Answer 14

oestrogen deficiency

Question 15

What is the pathophysiology behind effusions?

Answer 15

• the synovial lining becomes thickened and inflamed
• producing excess synovial fluid (effusions)