Osteoarthritis
A degenerative joint disease where the protective cartilage that cushions the ends of bones wears down over time, causing pain, stiffness, and reduced mobility.
Extended Definition
Osteoarthritis (OA) is the most common form of arthritis, affecting millions of people worldwide. It occurs when the cartilage—the smooth, protective tissue covering the ends of bones in a joint—gradually breaks down. As cartilage deteriorates, bones may begin to rub against each other, causing pain, swelling, and stiffness.
Unlike rheumatoid arthritis, which is an autoimmune condition, osteoarthritis is primarily a mechanical “wear and tear” disease. It typically develops slowly over many years and most commonly affects weight-bearing joints like knees, hips, and spine, as well as hands.
Risk factors include age (over 50), previous joint injuries, obesity, repetitive stress on joints, genetics, and bone deformities. While there’s no cure for osteoarthritis, various treatments can help manage symptoms and improve quality of life, including lifestyle modifications, physical therapy, medications, injections, and in severe cases, joint replacement surgery.
Related Terms
More Conditions Terms
View allBilateral Arthritis
Arthritis affecting the same joint on both sides of the body, such as both knees or both hips. Common in osteoarthritis due to similar wear patterns.
Bone Spur
A smooth, bony growth that develops along the edges of bones, especially in joints affected by osteoarthritis. Also called an osteophyte.
Bone-on-Bone
A colloquial term describing advanced osteoarthritis where cartilage has worn away completely, allowing direct contact between bone surfaces. Often painful and may require surgery.
Chondromalacia
Softening and deterioration of cartilage, most commonly affecting the underside of the kneecap. Often considered an early stage of patellofemoral arthritis.
Crepitus
A crackling, popping, or grinding sensation or sound that occurs during joint movement, often felt or heard when bones with damaged cartilage rub together.