Osteoarthritis

Question 1

Define Osteoarthritis

Answer 1

Chronic slow progressive disorder due to failure of ARTICULAR CARTILAGE

Question 2

Which joints does it affect

Answer 2

Hand: Proximal & distal interphalangeal joints, first carpo-metacarpal joints

Spine

Weight-bearing joints (hips & knees)

Question 3

Symptoms?

Answer 3

Joint pain, crepitus, instability, enlargement, stiffness
Limited motion
Worse with activity

Question 4

Rhuematoid vs osteoarthritis?

Answer 4

Osteoarthritis:
NO osteopenia or bony erosions
OSTEOPHYTES present

Question 5

Causes?

Answer 5

Excessive load on joints

Abnormal joint components (e.g. articular cartilage)

Question 6

Structure and function of articular cartilage?

Answer 6

WEIGHT-BEARING and allows movement of joints
Components:
1. Type 2 collagen
2. CHONDROCYTES
3. AGGRECANS (proteoglycans)
4. HYALURONIC ACID - important for maintaining synovial fluid viscosity

Question 7

Mechanism of osteoarthritis?

Answer 7

Cartilage changes:

• reduced proteoglycan + collagen
• chondrocyte changes (e.g. apoptosis)

Bone changes:
OSTEOPHYTES (new bone at joint margins)
Sclerotic bone formation

Question 8

Management?

Answer 8

Education
Physical therapy
Occupation therapy
Weight loss?
Exercise
Analgesia (paracetamol, NSAIDs, corticosteroids)
Joint replacement if severe