Osteoarthritis UK: Symptoms, Joints Affected & Management

A clinically reviewed UK conditions guide to osteoarthritis — who gets it, joints affected, causes and risk factors, diagnosis, disease staging, and evidence-based treatment options.

What Is Osteoarthritis?

Osteoarthritis is a chronic joint disease characterised by the progressive breakdown of articular cartilage — the smooth tissue that covers the ends of bones within a joint — alongside changes to the underlying bone, joint lining, ligaments, and surrounding muscles. It is not simply “wear and tear” (a term that is both imprecise and unhelpfully fatalistic) — it involves active biological processes including low-grade inflammation that contribute to pain and structural change.

The distinction matters clinically. OA flares have a genuine inflammatory component, which is why anti-inflammatory treatment is effective during flares. But OA is not primarily an inflammatory disease in the same way as rheumatoid arthritis — the inflammation is secondary to structural joint change rather than driving it. This means the treatment approach differs: exercise and load management are as important as medication.

Who Gets Osteoarthritis?

OA becomes significantly more prevalent with age — it is uncommon before 45 and very common over 65. However, it is not an inevitable consequence of ageing: many people in their 80s have minimal OA, while others develop significant OA in their 40s or 50s. Age is a risk factor, not a cause.

OA is more common in women than men, particularly for hand and knee OA. The sex difference becomes more pronounced after the menopause, suggesting oestrogen plays a protective role in joint health.

Joints Most Commonly Affected

Causes and Risk Factors

• Age — the single strongest risk factor; cumulative joint loading over time and reduced cartilage repair capacity
• Obesity — strongly associated with knee and hip OA; each kilogram of body weight imposes approximately 3–5kg of force on the knee during walking; also has metabolic and inflammatory effects independent of load
• Previous joint injury — anterior cruciate ligament tears, meniscal injuries, and intra-articular fractures substantially increase future OA risk in the affected joint
• Occupational factors — jobs involving repetitive kneeling, squatting, or heavy lifting increase knee and hip OA risk
• Genetics — significant hereditary component, particularly for hand and hip OA; first-degree relatives of OA patients have 2–3× higher risk
• Joint malalignment — varus (bow-legged) or valgus (knock-kneed) alignment increases compartmental loading; joint dysplasia increases hip OA risk
• Sex — women, particularly post-menopausal, have higher rates of OA

Symptoms

• Joint pain — typically a deep, aching pain; worsened by activity and weight-bearing; relieved by rest (though severe OA causes rest pain and night pain)
• Morning stiffness — characteristically brief (<30 minutes); longer morning stiffness suggests inflammatory arthritis rather than OA
• Stiffness after inactivity — “gelling”; stiffness on rising from a chair or after prolonged sitting; improves quickly with movement
• Crepitus — a grating, creaking, or grinding sensation within the joint; caused by articular surface irregularity
• Reduced range of movement — joint feels stiff and restricted; functional consequences depend on the joint affected
• Joint swelling — can occur, particularly in knee OA; combination of osteophytes (bony enlargement), synovitis, and effusion
• Flares — intermittent episodes of increased pain and swelling lasting days to weeks; often precipitated by overactivity, minor trauma, or changes in weather

Diagnosis

OA is diagnosed clinically in most cases. NICE guidance states that OA can be diagnosed in adults over 45 with activity-related joint pain and either no morning stiffness or morning stiffness lasting less than 30 minutes — without requiring investigations. X-ray can confirm the diagnosis and grade severity but is not required for initial management.

Classic X-ray features of OA are: LOSS — Loss of joint space, Osteophytes, Subchondral sclerosis, Subchondral cysts. MRI is rarely needed for OA management but may be used to assess meniscal or ligament pathology in younger patients or when considering surgery.

Blood tests are normal in OA and are used mainly to exclude inflammatory arthritis (negative RF, normal CRP and ESR in OA).

Disease Stages

Treatment Overview

The core of OA management is non-pharmacological. Exercise — land-based and aquatic — is the single most evidence-based intervention for OA and more effective than many medicines for long-term outcomes. Weight management is equally important for lower-limb OA.

When to Seek Help

• Joint pain significantly affecting your daily activities, sleep, or quality of life
• Sudden severe worsening of a joint that was previously manageable — may indicate an acute flare, crystal arthropathy, or haemarthrosis
• Joint that becomes hot, red, and acutely swollen — possible septic arthritis (infected joint), which requires emergency assessment
• Progressive loss of joint function despite conservative management — orthopaedic referral for consideration of joint replacement