The joints of the wrist and hand are often involved, but RA can affect other joints as well. Joint stiffness tends to be worse in the morning or after a long rest.
To understand how RA affects joints, it first helps to understand some of the components of a healthy joint. A joint refers to a place in the body where two or more bones meet. The ends of the bones are covered in cartilage, which absorbs shock and allows the joint to work more smoothly. Surrounding the joint is a protective capsule that is lined with tissue called synovium. The synovium produces fluid that nourishes and lubricates the joint.1
In RA, the synovium becomes inflamed. The inflammation causes the joint pain and swelling, and can also damage bone and cartilage in the joint. This damage to bone and cartilage is thought to begin early in the course of the disease, highlighting the important of early diagnosis and treatment. Surrounding muscles, ligaments, and tendons can also be affected.
Symptoms related to inflammation
- Prolonged morning stiffness of the spine lasting hours
- Spine stiffness associated with sitting for variable lengths of time
- Back pain improvement with exercise
- Eye inflammation – iritis
- Radiating leg pain – pseudosciatica
Other Effects of RA
Rheumatoid arthritis can affect the entire body, particularly if the RA becomes severe.2 In addition to joint problems, people with RA may notice occasional fevers, fatigue, and a sense of being generally unwell. RA can lead to anemia (low red blood cell count) and, less commonly, to problems with the blood vessels, lungs, heart, and other organs.
General Symptoms of RA
- Disordered sleep
- Mild weight loss
RA is an autoimmune disease. An autoimmune disease occurs when the immune system—which normally protects the body from infection—turns against some of the body’s own tissues. Other examples of autoimmune diseases are Type I diabetes, lupus, Sjogren syndrome, Grave’s Disease, and multiple sclerosis.
In the case of RA, the immune system attacks the synovium and causes inflammation. It’s unclear what starts this process, but some combination of genetic and environmental factors is likely to play a role. Factors that increase the likelihood of RA include being female, smoking, and having a family history of rheumatoid arthritis.3,4
Although family history may contribute to RA, it does not entirely explain an individual’s risk. Many people with a family history of RA will never develop the condition themselves. Similarly, RA may develop in someone with no family history of the condition.
RA is not contagious (people cannot “catch” RA from someone else).
What are rheumatoid nodules?
Rheumatoid nodules are firm lumps located just under the skin. The nodules most commonly grow close to the affected joints and can be as small as a pea and as large as a chestnut. The nodules can be firmly connected to tendons or fascia under the skin or quite moveable. Rheumatoid nodules are also often found at pressure points, including the hands, fingers, knuckles, or elbows; however, they may appear almost anywhere, including the lungs, heart, other internal organs, and even on the vocal cords, causing hoarseness.
Nodules can be asymptomatic or quite painful, but they are typically not problematic unless they interfere with daily activities by putting pressure on nerves or by limiting joint movement. Rheumatoid nodules in areas such as the heart and lungs may affect organ function.
What are the causes of rheumatoid nodules?
Rheumatoid nodules usually occur in patients with more severe disease. Nearly all patients with nodules will test positive for rheumatoid factor, and studies have suggested that when RA is linked with a positive rheumatoid factor test, it may indicate more aggressive disease. Other risk factors that may lead to the development of rheumatoid nodules include cigarette smoking and the use of Methotrexate, a drug commonly used to treat RA.
1 National Institutes of Health, National Institute of Arthritis and Musculoskeletal and Skin Disease. Handout on Health: Rheumatoid Arthritis. Last revised April 2009.
2 Young A, Koduri G. Extra-articular manifestations and complications of rheumatoid arthritis. Best Practice & Research Clinical Rheumatology. 2007;21:907-27.