• Also Known As:
  • OA
  • Degenerative Joint Disease
  • DJD
  • Osteoarthrosis
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What is osteoarthritis?

Osteoarthritis (OA) is the most common form of arthritis, affecting over 30 million people in the United States. Also called degenerative joint disease (DJD), OA is associated with joint injury and with the aging process (“wear and tear”). The joints most commonly affected by OA are those of the hips, knees, and spine (neck and lower back) as well as the fingers and thumbs.

OA is a chronic, progressive disease that causes deterioration of the joint cartilage and the formation of new bone (bone spurs) at the edges of the joints. Cartilage and synovial fluid are meant to provide a smooth, low-friction transition between the ends of bones. When cartilage loses its elasticity and wears down, joint movement becomes less smooth. Eventually, cartilage can completely erode and the opposing bone ends rub together. This leads to joint pain that may be intermittent or chronic, to stiffness in the morning and after rest, to small pieces of bone and fragments of cartilage in the remaining synovial fluid, and to a loss of coordination, posture, and mobility.

It is uncommon to see OA in people under 40 years of age. More men than women have OA before age 45 while it is more common in women after the age of 45. Overall, women, particularly elderly women, are more likely to develop OA than men. This is thought to be possibly related to menopausal hormone loss, though not fully understood why, or to long-term stress on the knees from women’s broader hips.

Athletes who sustain multiple joint injuries over time also can be affected by OA. The primary cause is mechanical, such as joint damage caused by running or excess weight-bearing activities. For example, recreational runners may be prone to hip OA but less so to knee OA while professional runners (e.g., Olympic athletes) tend to be at greater risk of both hip and knee OA. However, any major injury to bone, joints, tendons, or ligaments (e.g., anterior cruciate ligament – ACL, meniscal tears) can increase the risk of OA. Repetitive motion or heavy weight-bearing activities as seen in certain occupations or with leisure activities can also contribute to developing OA.

More rarely, OA may be metabolic, genetic, or chemical in nature. In some studies, up to 50% of hand and hip cases were attributed to a positive family history of OA. Muscle weakness and anatomic misalignment (e.g., knock-kneed, bowlegged) can increase the risk of developing OA.

It is expected that the number of OA cases will almost double by the year 2020 due to increased longevity of the general population and the prevalence of obesity. Increased body weight can cause significant stress on the knees; three to six times a person’s body weight is placed on knee joints during a normal, single stride. Excess body weight exacerbates this stress, increasing the risk of OA within the joint area.


About Osteoarthritis


The goals of testing are to distinguish osteoarthritis (OA) from other forms of arthritis and causes of joint pain and stiffness and to monitor the side effects of various treatments.

Laboratory tests
In general, blood tests are not considered useful in diagnosing osteoarthritis. It is usually diagnosed using someone’s personal and family medical histories, a physical exam, X-rays, and in some cases with an examination of synovial fluid from an affected joint. Tests that may be ordered to rule out other conditions and to evaluate the person’s health include:

Non-laboratory tests

  • X-rays of the affected joints may show loss of cartilage, bone damage, bone spurs, and narrowing of the joint space but will frequently not show significant changes early in the disease.
  • MRI (magnetic resonance imaging) – may also be used to examine affected joints


The goals of treatment for osteoarthritis (OA) are to relieve pain, maintain and improve joint mobility, and to minimize further joint damage. OA cannot be cured, but a combination of treatment alternatives can be successful at controlling pain and improving joint function. Exercise is one of the best therapies for those with OA and weight loss is important for those who are overweight. Non-drug therapies include the use of hot and cold treatments and massage.

There are also several medications available to alleviate symptoms. Acetaminophen is an over-the-counter drug that is commonly recommended for pain management. Other medications to control pain include non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen; COX-2 inhibitors, such as celecoxib, which act like NSAIDs but have been shown to minimize gastric ulcer complications often seen with NSAID use; and steroids, such as cortisone, which are injected directly into the affected joint to help relieve pain.

Artificial joint fluid is sometimes injected into affected knees by an orthopedic surgeon, and joint surgery may be necessary to replace or repair damaged joints in severe cases of OA.

Many of these treatments may have associated risks and side effects. Patients should talk to their health care provider about current treatment options and weigh the benefits against the risks in their own situation. Researchers continue to examine other drugs that could be useful in preventing, slowing down, or reversing joint damage and in pain management.

View Sources

Sources Used in Current Review

Centers for Disease Control and Prevention. 2017. Osteoarthritis Fact Sheet. Available online at https://www.cdc.gov/arthritis/basics/osteoarthritis.htm. Accessed July 27, 2017.

Kalunian, Kenneth MD. 2017. Patient education: Osteoarthritis treatment (Beyond the Basics). Available online https://www.uptodate.com/contents/osteoarthritis-treatment-beyond-the-basics. Accessed July 28, 2017.

NIH: U. S. National Library of Medicine. 2017. Osteoarthritis. Available online at https://medlineplus.gov/ency/article/000423.htm. Accessed July 28, 2017.

Pereira, Duarte, et. al. 2015. Acta Medica Portugesa. Arthritis. Available online at http://www.actamedicaportuguesa.com/revista/index.php/amp/article/view/5477/4229. Accessed July 28, 2017.

(March 20, 2017) Lozada, C. Osteoarthritis. Medscape Reference. Available online at http://emedicine.medscape.com/article/330487-overview. Accessed July 2017.

Sources Used in Previous Reviews

Arthritis Foundation. Osteoarthritis. Available online at http://www.arthritis.org/conditions-treatments/disease-center/osteoarthritis/. Accessed August 2013.

Arthritis Foundation. Who Gets Osteoarthritis? Available online at http://www.arthritis.org/who-gets-osteoarthritis.php. Accessed August 2013.

National Institute of Arthritis and Musculoskeletal and Skin Diseases. Handout on Health: Osteoarthritis. Available online at http://www.niams.nih.gov/Health_Info/Osteoarthritis/default.asp#2. Accessed August 2013.

Patient Education Institute. MedlinePlus Interactive Tutorial: Osteoarthritis. Available online at http://www.nlm.nih.gov/medlineplus/tutorials/osteoarthritis/op189105.pdf. Accessed August 2013.

MayoClinic.com. Osteoarthritis. Available online at http://www.mayoclinic.com/health/osteoarthritis/DS00019. Accessed August 2013.

Up To Date. Osteoarthritis symptoms and diagnosis. Available online at http://www.uptodate.com/contents/osteoarthritis-symptoms-and-diagnosis-beyond-the-basics. Accessed August 2013.

Hospital for Special Surgery. Diagnosing Osteoarthritis. Available online at http://www.hss.edu/osteoarthritis-diagnosis.asp. Accessed August 2013.

Silverstein FE, Faich G, Goldstein JL, et al. Gastrointestinal Toxicity With Celecoxib vs Nonsteroidal Anti-inflammatory Drugs for Osteoarthritis and Rheumatoid Arthritis. The CLASS Study: A Randomized Controlled Trial. JAMA. 2000;284(10):1247-1255.

Felson DT. Chapter 332. Osteoarthritis. In: Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison’s Principles of Internal Medicine. 18th ed. New York: McGraw-Hill; 2012. Available online at http://www.accessmedicine.com/content.aspx?aID=9139147. Accessed September 9, 2013.

(© 2006) Osteoarthritis. Arthritis Foundation Disease Center [On-line information]. Available online at http://www.arthritis.org/conditions/diseasecenter/OA/.

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MayoClinic.com. Osteoarthritis – Risk Factors. Available online at http://www.mayoclinic.com/health/osteoarthritis/DS00019/DSECTION=risk-factors. Accessed October 2010.