Adults only (18+)

What Is OA Arthritis?

Understanding Osteoarthritis (OA)

Osteoarthritis, often abbreviated as OA, is the most common form of arthritis. It is a degenerative joint disease characterised by the gradual breakdown of cartilage—the smooth, protective tissue that cushions the ends of bones within a joint. As cartilage wears away, bones begin to rub directly against each other, leading to pain, stiffness and reduced joint mobility. OA primarily affects older adults but can also develop earlier due to injury, repetitive stress or genetic factors.

Causes and Risk Factors

Osteoarthritis develops over time as joints undergo wear and tear. Age is the most significant risk factor, as cartilage naturally becomes thinner and less resilient with ageing. Joint injuries, repetitive movements (common in certain occupations or sports), obesity and genetic predisposition can accelerate cartilage deterioration. Unlike autoimmune arthritis, OA is not caused by immune system dysfunction but by mechanical and biological changes in joint tissues.

Common Symptoms

People with osteoarthritis commonly experience joint pain that worsens with activity and improves with rest. Stiffness is especially noticeable after periods of inactivity, such as in the morning or after sitting. Joints may feel swollen or tender, and movement can become limited. Crepitus—a grinding or crackling sensation during joint movement—is also common due to roughened cartilage surfaces and bone changes.

Joints Commonly Affected

OA most frequently affects weight-bearing joints such as the knees, hips and spine. It also commonly involves the hands, particularly the finger joints near the fingertips (Heberden’s nodes) and middle joints (Bouchard’s nodes). Symptoms and severity can vary widely between individuals.

Diagnosis and Treatment

Diagnosis involves a clinical examination and imaging tests like X-rays to assess cartilage loss and bone changes. Treatment focuses on managing symptoms and improving function through pain relief medications, physical therapy, exercise and weight management. In severe cases, joint replacement surgery may be necessary.

Summary

Osteoarthritis (OA) is a degenerative joint disease caused by cartilage breakdown, leading to joint pain, stiffness and reduced mobility. It primarily affects older adults and weight-bearing joints. Management includes medication, exercise and sometimes surgery.