Osteoarthritis

Definition/diagnostic criteria Osteoarthritis (OA) is a degenerative joint disease characterised by progressive cartilage deterioration, joint space narrowing, osteophyte formation and subchondral sclerosis. It results in joint pain, usually accompanied by varying degrees of functional limitation and reduced quality of life. Diagnosis is primarily clinical, based on symptoms and physical findings rather than definitive laboratory or imaging tests.

Epidemiology OA is the most common form of arthritis in the UK, affecting millions of people. Its prevalence increases with age, particularly in individuals over 50 years. It affects an estimated 10% of men and 18% of women over 60. Obesity, joint injury and genetics are notable risk factors.

Diagnosis
Clinical features:

• Pain – often worsens with joint use and improves with rest.
• Stiffness, typically less than 30 minutes, often described as ‘gelling’ stiffness.
• Limited range of motion and crepitus.
• Bony swelling – osteophyte formation leading to joint enlargement.
• Tenderness on palpation.

Investigations: Routine laboratory tests are not necessary for diagnosis but may be used to exclude other conditions. Radiographic findings, while not always correlating with symptoms, typically include:

• Joint space narrowing.
• Subchondral bone sclerosis.
• Osteophyte formation.
• Possible cystic areas.

Treatment Management is primarily non-pharmacological and pharmacological:

Non-pharmacological:

• Patient education and self-management.
• Exercise, tailored to the individual, focusing on muscle strengthening and general fitness.
• Weight management for overweight or obese patients.
• Assistive devices if needed.

Pharmacological:

• Analgesia – paracetamol is often the first choice.
• Topical NSAIDs, for knee or hand OA.
• Oral NSAIDs/COX-2 inhibitors – consider if adequate pain relief is not achieved with paracetamol or topical NSAIDs. Use the lowest effective dose for the shortest duration.
• Intra-articular corticosteroids, for moderate to severe pain in people with OA, especially with evidence of local inflammation.

Referral for specialist assessment may be considered for severe symptoms, atypical presentation, or when surgery (like joint replacement) is contemplated.

Prognosis OA is a chronic condition with a variable course. Symptoms can fluctuate, but there is generally a gradual worsening over time. Joint damage is irreversible, but symptom control and improved function can often be achieved with appropriate management. Quality of life can be significantly affected, and OA is a major cause of disability among older adults.