Osteoarthritis

Question 1

What is osteoarthritis?

Answer 1

Condition characterised by progressive loss of articular cartilage and remodelling of the underlying bone

Question 2

Describe the pathogenesis of OA

Answer 2

Degradation of cartilage and remodelling of bone due to an active response of the chondrocytes in the articular cartilage and inflammatory cells in surrounding tissues
The release of enzymes from these cells break down collagen and proteoglycans, destroying the articular cartilage.
The exposure of the subchondral bone results in sclerosis, followed by reactive remodelling changes that lead to formation of osteophytes and subchondral bone cysts. The joint space is progressively lost.

Question 3

What are the two types of OA

Answer 3

Primary and secondary

Question 4

Give risk factors for primary OA

Answer 4

Female, increased age, manual labour occupation and obesity

Question 5

Give the causes of secondary OA

Answer 5

Trauma
Infiltrative disease
Connective tissue disease

Question 6

Which joints are commonly affected by OA?

Answer 6

Hands
Feet
Knees
Hips

Question 7

Give the typical symptoms of OA

Answer 7

Chronic and gradually worsening pain and stiffness.
Pain worsens with activity over the course of the day whereas stiffness decreases with activity.
If chronic, may have deformity
Pain is relieved by rest

Question 8

Give the typical findings on examination in OA

Answer 8

Bouchards nodes - PIPJ
Heberden's nodes - DIPJ
Fixed flexion deformity 
Varus malalignment of the knees 
Crepitus

Question 9

Give the investigations for OA

Answer 9

Clinical diagnosis

Bloods and imaging to rule out infective/inflammatory cause and fractures

Question 10

Describe the classical radiological features of OA

Answer 10

Loss of joint space
Subchondral sclerosis
Subchondral cysts
Osteophytes

Question 11

Describe the management of OA

Answer 11

Conservative - encourage exercise, educate the patient, encourage weight loss, local heat and ice, joint supports
Medical - simple analgesia and topical NSAIDs, intra-articular joint injections
Surgical - Osteotomy, arthrodesis (joint fusion) and arthroplasty