The Difference between Rheumatoid Arthritis and Osteoarthritis

Rheumatoid arthritis and osteoarthritis are both relatively common arthritic conditions.  Both cause joint pain and both can be extremely debilitating in those who suffer from the conditions.  There are, however, differences between the two arthritic conditions that you should know about when trying to decide which type of arthritis you have.

The Difference between Rheumatoid Arthritis and Osteoarthritis

Here are some key differences between the two types of arthritis:

  • Rheumatoid arthritis is an autoimmune disease. Rheumatoid arthritis is caused by autoantibodies made by the immune system of the person who has the disease. The autoantibodies attack the connective tissue around the joints, causing inflammation and pain.  On the contrary, there are no autoantibodies in osteoarthritis, which instead is secondary to wear and tear on the joints over time.
  • Rheumatoid arthritis affects the small joints more than the large joints. People with rheumatoid arthritis can have all of their joints affected but appear to have more problems with the small joints of the feet and hands.  In contrast, osteoarthritis affects the larger weight-bearing joints, such as the knees and hips.  People who use their hands a lot can get pain and inflammation of the hands but different joints are affected in osteoarthritis than are affected in rheumatoid arthritis.
  • Rheumatoid arthritis can be diagnosed with a blood test. Doctors can check for the level of rheumatoid factor (RF) in the bloodstream in order to make the diagnosis of rheumatoid arthritis.  Rheumatoid factor is seen primarily just in rheumatoid arthritis and is a measurement of the autoantibodies that cause the disease.  There is no blood test that can detect osteoarthritis.  Instead, the diagnosis is a clinical one, based on the changes the doctor can see with the naked eye or with an x-ray showing the telltale signs of osteoarthritic changes in the joint.
  • Rheumatoid arthritis involves redness to the joints. Because there is inflammation in the joints of rheumatoid arthritis, the joints affected are often red and swollen.  The redness can be seen by the naked eye and reflects the amount of inflammation going on inside and around the joints themselves.  In contrast, there usually isn’t any redness around the joints of people who are suffering from osteoarthritis.
  • Different joints in the hands are affected. While both osteoarthritis sufferers and rheumatoid arthritis sufferers have arthritic changes in the hands, there are different joints involved in each type of arthritis. Rheumatoid arthritis mostly affects the metacarpal-phalangeal joints (MP joints) of the hands, while osteoarthritis affects the interphalangeal joints (IP joints).  The doctor can simply look at the hands or do an x-ray that can tell the difference between the two forms of arthritis.
  • Rheumatoid arthritis is often bilateral. Rheumatoid arthritis usually affects both sides of the body equally, while in osteoarthritis, the arthritic changes may or may not be bilateral. For example, if the person suffered a knee injury and secondarily got osteoarthritis, the injured knee would be more severely involved in osteoarthritis when compared to the knee that was not injured.

Rheumatoid arthritis can be treated with biologic agents.  The treatment of osteoarthritis strictly involves taking nonsteroidal anti-inflammatory medications while biologic agents and chemotherapy can be used to treat rheumatoid arthritis.  There are a wider range of choices of treatment for rheumatoid arthritis when compared to osteoarthritis.

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