What Are Rheumatic Diseases and What Is Arthritis?
Rheumatic diseases are characterized by inflammation (signs are redness and/or heat, swelling, and pain) and loss of function of one or more connecting or supporting structures of the body. They especially affect joints, tendons, ligaments, bones, and muscles. Common symptoms are pain, swelling, and stiffness. Some rheumatic diseases can also involve internal organs. There are more than 100 rheumatic diseases. Many people use the word “arthritis” to refer to all rheumatic diseases. However, the word literally means joint inflammation. The many different kinds of arthritis comprise just a portion of the rheumatic diseases. Some rheumatic diseases are described as connective tissue diseases because they affect the supporting framework of the body and its internal organs. Others are known as autoimmune diseases because they occur when the immune system, which normally protects the body from infection and disease, harms the body’s own healthy tissues. Throughout this fact sheet the terms “arthritis” and “rheumatic diseases” are sometimes used interchangeably.
What Causes Arthritis Pain? Why Is It So Variable?
The pain of arthritis may come from different sources. These may include inflammation of the synovial membrane (tissue that lines the joints), the tendons, or the ligaments; muscle strain; and fatigue. A combination of these factors contributes to the intensity of the pain. The pain of arthritis varies greatly from person to person, for reasons that doctors do not yet understand completely. Factors that contribute to the pain include swelling within the joint, the amount of heat or redness present, or damage that has occurred within the joint. In addition, activities affect pain differently so that some patients note pain in their joints after first getting out of bed in the morning, whereas others develop pain after prolonged use of the joint.
Each individual has a different threshold and tolerance for pain, often affected by both physical and emotional factors. These can include depression, anxiety, and even hypersensitivity at the affected sites due to inflammation and tissue injury. This increased sensitivity appears to affect the amount of pain perceived by the individual. Social support networks can make an important contribution to pain management.
Examples of Rheumatic Diseases
This is the most common type of arthritis, affecting an estimated 21 million adults in the United States. Osteoarthritis primarily affects cartilage, which is the tissue that cushions the ends of bones within the joint. In osteoarthritis, the cartilage begins to fray and may entirely wear away. Osteoarthritis can cause joint pain and stiffness. Disability results most often when the disease affects the spine and the weight-bearing joints (the knees and hips).
- Rheumatoid arthritis
This inflammatory disease of the synovium, or lining of the joint, results in pain, stiffness, swelling, joint damage, and loss of function of the joints. Inflammation most often affects joints of the hands and feet and tends to be symmetrical (occurring equally on both sides of the body). This symmetry helps distinguish rheumatoid arthritis from other forms of the disease. About 1 percent of the U.S. population (about 2.1 million people) has rheumatoid arthritis.
- Juvenile rheumatoid arthritis
This is the most common form of arthritis in childhood, causing pain, stiffness, swelling, and loss of function of the joints. The arthritis may be associated with rashes or fevers, and may affect various parts of the body.
Fibromyalgia is a chronic disorder that causes pain throughout the tissues that support and move the bones and joints. Pain, stiffness, and localized tender points occur in the muscles and tendons, particularly those of the neck, spine, shoulders, and hips. Patients may also experience fatigue and sleep disturbances.
- Systemic lupus erythematosus
Systemic lupus erythematosus (also known as lupus or SLE) is an autoimmune disease in which the immune system harms the body’s own healthy cells and tissues. This can result in inflammation of and damage to the joints, skin, kidneys, heart, lungs, blood vessels, and brain.
Also known as systemic sclerosis, scleroderma means literally “hard skin.” The disease affects the skin, blood vessels, and joints. It may also affect internal organs, such as the lungs and kidneys. In scleroderma, there is an abnormal and excessive production of collagen (a fiber-like protein) in the skin or internal organs.
This group of rheumatic diseases principally affects the spine. One common form–ankylosing spondylitis–not only affects the spine, but may also affect the hips, shoulders, and knees as the tendons and ligaments around the bones and joints become inflamed, resulting in pain and stiffness. Ankylosing spondylitis tends to affect people in late adolescence or early adulthood. Reactive arthritis, sometimes called Reiter’s syndrome, is another spondyloarthropathy. It develops after an infection involving the lower urinary tract, bowel, or other organ and is commonly associated with eye problems, skin rashes, and mouth sores.
This type of arthritis results from deposits of needle-like crystals of uric acid in the joints. The crystals cause inflammation, swelling, and pain in the affected joint, which is often the big toe.
- Infectious arthritis
This is a general term used to describe forms of arthritis that are caused by infectious agents, such as bacteria or viruses. Parvovirus arthritis and gonococcal arthritis are examples of infectious arthritis. Arthritis symptoms may also occur in Lyme disease, which is caused by a bacterial infection following the bite of certain ticks. In those cases of arthritis caused by bacteria, early diagnosis and treatment with antibiotics are crucial to getting rid of the infection and minimize damage to the joints.
- Polymyalgia rheumatica
Because this disease involves tendons, muscles, ligaments, and tissues around the joint, symptoms often include pain, aching, and morning stiffness in the shoulders, hips, neck, and lower back. It is sometimes the first sign of giant cell arteritis, a disease of the arteries characterized by inflammation, weakness, weight loss, and fever.
This is a rheumatic disease that causes inflammation and weakness in the muscles. The disease may affect the whole body and cause disability.
- Psoriatic arthritis
This form of arthritis occurs in some patients with psoriasis, a scaling skin disorder. Psoriatic arthritis often affects the joints at the ends of the fingers and toes and is accompanied by changes in the fingernails and toenails. Back pain may occur if the spine is involved.
This condition involves inflammation of the bursae, small, fluid-filled sacs that help reduce friction between bones and other moving structures in the joints. The inflammation may result from arthritis in the joint or injury or infection of the bursae. Bursitis produces pain and tenderness and may limit the movement of nearby joints. Tendinitis (Tendonitis). This condition refers to inflammation of tendons (tough cords of tissue that connect muscle to bone) caused by overuse, injury, or a rheumatic condition. Tendinitis produces pain and tenderness and may restrict movement of nearby joints.
What Causes Rheumatic Disease?
Scientists are studying risk factors that increase the likelihood of developing a rheumatic disease. Some of these factors have been identified. For example, in osteoarthritis, inherited cartilage weakness or excessive stress on the joint from repeated injury may play a role. In lupus, rheumatoid arthritis, and scleroderma, the combination of genetic factors that determine susceptibility and environmental triggers are believed to be important. Family history also plays a role in some diseases such as gout and ankylosing spondylitis. Gender is another factor in some rheumatic diseases. Lupus, rheumatoid arthritis, scleroderma, and fibromyalgia are more common among women. This indicates that hormones or other male-female differences may play a role in the development of these conditions.
Who Is Affected by Arthritis and Rheumatic Conditions?
An estimated 43 million people in the United States have arthritis or other rheumatic conditions. By the year 2020, this number is expected to reach 60 million. Rheumatic diseases are the leading cause of disability among adults age 65 and older. Rheumatic diseases affect people of all races and ages. Some rheumatic conditions are more common among certain populations. For example: Rheumatoid arthritis occurs two to three times more often in women than in men. Scleroderma is more common in women than in men. Nine out of 10 people who have lupus are women. Nine out of 10 people who have fibromyalgia are women.
Gout is more common in men than in women. Lupus is three times more common in African American women than in Caucasian women. Ankylosing spondylitis is more common in men than in women. What Are the Symptoms of Arthritis? Different types of arthritis have different symptoms. In general, people who have arthritis feel pain and stiffness in the joints. Some of the more common symptoms are listed below. Early diagnosis and treatment help decrease further joint damage and help control symptoms of arthritis and many other rheumatic diseases.
Common Symptoms of Arthritis
- Swelling in one or more joints.
- Stiffness around the joints that lasts for at least 1 hour in the early morning.
- Constant or recurring pain or tenderness in a joint.
- Difficulty using or moving a joint normally.
- Warmth and redness in a joint.