OA is a type of arthritis that is caused by the breakdown and eventual loss of the cartilage of one or more joints. Cartilage is a protein substance that serves as a cushion between the bones of the joints. OA is also known as degenerative arthritis. Among the over 100 different types of arthritis conditions, OA is the most common and occurs more frequently with age. Before age 45, OA occurs more frequently in males. After age 50, it occurs more frequently in females.1 OA commonly affects the hands, feet, spine and large weight-bearing joints, such as the hips and knees.2 Most cases of OA have no known cause and are referred to as primary OA.
Symptoms of OA manifest in patients as joint pain, tenderness, stiffness, limited joint movement, joint cracking or creaking (crepitation), locking of joints and local inflammation. OA can also lead to joint deformity in later stages of the disease. Many drugs are now used to treat the inflammation and pain associated with OA, including aspirin and other NSAIDs, such as ibuprofen and naproxen, that have a rapid analgesic and anti-inflammatory response.
- Lawrence RC, Felson DT, Helmick CG, Arnold LM, Choi H, Deyo RA, Gabriel S, Hirsch R, Hochberg MC, Hunder GG, Jordan JM, Katz JN, Maradit Kremers H, and Wolfe F for the National Arthritis Data Workgroup. “Estimates of the prevalence of arthritis and other rheumatic conditions in the United States: Part II.” Arthritis & Rheumatism. 2008;58(1):26-35.
- Arthritis Foundation. “What is Osteoarthritis?” http://www.arthritis.org/what-is-osteoarthritis.php. Accessed April 21, 2011.