OSTEOARTHRITIS

Question 1

What is the only cell found in hyaline cartilage? What happens to the cells in osteoarthritis?

Answer 1

Chondrocytes

when hyaline cartilage starts to break down the chondrocytes proliferate and attempt to repair by secreting proteases and cytokines. This repair is inadequate and they eventually die, exposing bone

Question 2

Why is osteoarthritis referred to as non-inflammatory even though there is inflammation?

Answer 2

Low white blood cell count in synovial fluid

Question 3

What are the 4 classic x-ray findings and osteoarthritis?

Answer 3

• Loss of joint space
• Osteophytes
• Subchondral sclerosis
• Subchondral cyst

Question 4

Why is there subchondral sclerosis in osteoarthritis?

Answer 4

Hyaline cartilage breaks down → bone on bone rubbing → increased collagen with abnormal mineralisation of bone

Question 5

The thickening of subchondral bone and joint margins cause which x-ray finding?

Answer 5

Osteophyte

Question 6

How are subchondral cysts formed?

Answer 6

Bone cracks/contusion and is filled with synovial fluid

Question 7

Which joint is often involved in osteoarthritis? Will it be one or both?

Answer 7

Both knees

Question 8

Explain the asymmetry of the loss of joint space in this x-ray

Answer 8

There is more weight-bearing on medial side of knee and therefore narrowing is expected more on this side

Question 9

What is this x-ray finding? What is it believed to be caused by?

Answer 9

Bouchard’s node

Believed to be caused by osteophytes

Question 10

Which joints of the spine are often involved in osteoarthritis?

Answer 10

Facet joints - particularly cervical and lumbar spine

Question 11

When do you expect the joint pain of osteoarthritis to worsen? What normally goes along with joint pain?

Answer 11

• Worsens after use of joint, at end of day and improves with rest
• Stiffness
• Restricted motion

Question 12

What is main non-modifiable risk factor for osteoarthritis? What is main modifiable risk factor?

Answer 12

• Female gender and advanced age
• Obesity (esp knee, hands, hip)

Question 13

What are the two main lifestyle modifications to improve osteoarthritis?

Answer 13

• Exercise, weight loss

Question 14

What is the definitive treatment for osteoarthritis?

Answer 14

Surgery: knee and hip replacements

Question 15

Acute onset monoarthritis must have which two causes excluded as an emergency?

Answer 15

• Septic arthritis
• Gout

Question 16

Which haematological condition very commonly presents with joint pain in young patients? How can this be differentiated from osteoarthritis?

Answer 16

Haemochromatosis

→ Mostly involves MCP joints and accompanies high serum ferritin level