Osteoarthritis
Osteoarthritis is the most common form of arthritis, a joint disease that can cause pain, stiffness, swelling, and reduced movement as joint tissues change over time.
What osteoarthritis is
Osteoarthritis is a chronic joint disease that develops as joint tissues change over time. It has often been described as wear and tear, but that phrase is too simple. Cartilage, bone, joint lining, ligaments, tendons, and muscles can all contribute to pain, stiffness, swelling, and reduced function.
How joints change
Healthy cartilage helps bones move smoothly against each other. In osteoarthritis, cartilage can break down and the joint may respond by changing nearby bone, forming bony growths, and becoming inflamed. Pain does not always match the amount of change seen on an X-ray, because nerves, inflammation, muscle strength, and movement patterns also matter.
Symptoms
Common symptoms include joint pain during or after activity, stiffness after rest, swelling, tenderness, reduced range of motion, and grinding or clicking sensations. Symptoms often develop gradually. Some people have mild imaging changes with significant pain, while others have obvious joint changes and fewer symptoms.
Risk factors
Risk increases with age, previous joint injury, repetitive joint stress, higher body weight, family history, joint shape, muscle weakness, and some medical conditions. Osteoarthritis can affect younger adults after injuries or heavy joint stress, but it becomes more common later in life.
Diagnosis
Clinicians diagnose osteoarthritis using symptoms, medical history, physical examination, and sometimes imaging or lab tests. X-rays can show joint space narrowing, bone changes, or osteophytes, but they are not always needed for every case. Blood tests may help rule out inflammatory or other types of arthritis when the pattern is unclear.
Management goals
Management focuses on reducing pain, improving movement, protecting joints, and supporting daily life. Plans can include physical activity, strengthening, weight management when relevant, assistive devices, heat or cold, education programs, medicines for pain, injections for selected cases, and surgery when severe joint damage limits function.
Movement and self-management
Appropriate movement is often part of osteoarthritis care, even when a joint hurts. Low-impact aerobic activity, strengthening, stretching, balance work, and pacing can help many people maintain function. A clinician or physical therapist can help match activity to the joint, symptoms, and other health conditions.
Why it matters
Osteoarthritis matters because joint pain can reshape work, sleep, mobility, independence, mood, and physical activity. It is common enough to be a public health issue, but personal enough that care must fit the specific joint, person, goals, and daily environment.