Types of Arthritis

Did you know there is more than one type of arthritis? In fact, there are more than 100 types of arthritis. It's a condition that affects more than 46 million U.S. adults -- a number that's expected to increase to 67 million adults by the year 2030.

The false notion that all arthritis is alike has led people to try treatments that have little effect on their arthritis symptoms. Since each type of arthritis is different, each type calls for a different approach to treatment. That means an accurate diagnosis is crucial for anyone who has arthritis. With the proper diagnosis, you'll know what causes thepain. Then, you can be sure you're taking the proper steps to relieve the pain and continue to be active.

What Are the Common Types of Arthritis?

There are two major types of arthritis --osteoarthritis, which is the "wear and tear" arthritis, and rheumatoid arthritis, an inflammatory type of arthritis that happens when the body's immune system does not work properly.

Gout, which is caused by crystals that collect in the joints, is another common type of arthritis. Psoriatic arthritis,lupus, and septic arthritis are other types of the condition.

What Is Osteoarthritis?

Osteoarthritis is also called degenerative joint disease or degenerative arthritis. It affects about 33 million Americans and is the most common chronic joint condition.

Osteoarthritis results from overuse of joints. It can be the consequence of demanding sports, obesity, or aging. If you were an athlete or dancer in high school or college, you may be wondering why your knee or hip aches when you climb out of bed in the morning. Ask your doctor about osteoarthritis. It can strike earlier in life with athletes or those who suffered an injury in young adulthood. Osteoarthritis in the hands is frequently inherited and often happens in middle-aged women.

Osteoarthritis is most common in joints that bear weight -- such as the knees, hips, feet, and spine. It often comes on gradually over months or even years. Except for the pain in the affected joint, you usually do not feel sick, and there is no unusual fatigue or tiredness as there is with some other types of arthritis.

With osteoarthritis, the cartilage gradually breaks down. Cartilage is a slippery material that covers the ends of bones and serves as the body's shock absorber. As more damage occurs, the cartilage starts to wear away, or it doesn't work as well as it once did to cushion the joint. As an example, the extra stress on knees from being overweight can cause damage to knee cartilage. That, in turn, causes the cartilage to wear out faster than normal.

As the cartilage becomes worn, cushioning effect of the joint is lost. The result is pain when the joint is moved. Along with the pain, sometimes you may hear a grating sound when the roughened cartilage on the surface of the bones rubs together. Painful spurs or bumps may appear on the end of the bones, especially on the fingers and feet. While not a major symptom of osteoarthritis, inflammation may occur in the joint lining as a response to the breakdown of cartilage.

What Are the Symptoms of Osteoarthritis?

Symptoms of osteoarthritis, depending on which joint or joints are affected, may include:

• Deep, aching pain 
• Difficulty dressing or combing hair
• Difficulty gripping objects
• Difficulty sitting or bending over
• Joint being warm to the touch
• Morning stiffness for less than an hour
• Pain when walking
• Stiffness after resting
• Swelling of joint
• Loss of motion in a joint

What Are Common Risk Factors for Osteoarthritis?

Risk factors for osteoarthritis include:

• Abnormal alignment of the joints
• Age
• Athletics (wear-and-tear and injuries from sports and athletics)
• Changing forces (putting weight on one knee or hip)
• Gender
• Heavy, constant joint use
• Joint injury by other types of arthritis
• Knee surgery
• Overuse or injury
• Obesity or being overweight

Osteoarthritis is very common and can coexist with other types of arthritis such as rheumatoid or gout.

What Is Rheumatoid Arthritis?

Rheumatoid arthritis is the most common type of inflammatory arthritis. More than 1.3 million Americans are affected. According to the American College of Rheumatology, about 75% of those affected are women. In fact, between 1% and 3% of women are likely to develop rheumatoid arthritis in their lifetime.

Rheumatoid arthritis is an autoimmune disease. That means that the immune system attacks parts of the body. For reasons that aren't clear, the joints are the main areas affected by this malfunction in the immune system. Over time, chronic inflammation can lead to severejoint damage and deformities. About one out of every five people who have rheumatoid arthritis develop lumps on their skin calledrheumatoid nodules. These often develop over joint areas that receive pressure, such as over knuckles, elbows, or heels.

What Are the Symptoms of Rheumatoid Arthritis?

Symptoms of rheumatoid arthritis can come on gradually or start suddenly. Unlike osteoarthritis, symptoms of rheumatoid arthritis are often more severe, causing pain, fatigue, loss of appetite, stiffness.

With rheumatoid arthritis, you may feel pain and stiffness and experience swelling in your hands, wrists, elbows, shoulders, knees, ankles, feet, jaw, and neck. Sometimes the pain occurs in one body part. But more commonly, rheumatoid arthritis pain occurs in combinations of several joints such as in the hands, knees, and feet.

With rheumatoid arthritis, the joints tend to be involved in a symmetrical pattern. That is, if the knuckles on the left hand are inflamed, the knuckles on the right hand will also be inflamed. After a period of time, more of your joints may gradually become involved with pain and swelling and may feel warm to the touch. The joint swelling is persistent and interferes with activities. For example, it can interfere with opening a jar, driving, working, and walking -- the very activities that allow us to function in our daily lives.

The stiffness on arising in the morning, which may have started as a temporary nuisance, can soon last for hours or even most of the day. Fatigue can be debilitating. Inflammation can cause reduced appetite and weight loss. Fever, rash, and even involvement of the heart or lungs and eyes can occur with rheumatoid arthritis. These feelings and symptoms -- other than joint pain and the inflammation in other organs -- happen when the damage done by the immune system spills over from the joints to other areas of the body.

What Causes Rheumatoid Arthritis?

With rheumatoid arthritis, some of your body's cells recognize one of your own proteins as a foreign intruder. The exact protein involved in rheumatoid arthritis has not yet been discovered. Some experts believe the immune system becomes "confused" after infection with a bacteria or virus and begins attacking the normal joint tissues. Certain immune cells called lymphocytes are stimulated to react to this protein. The reaction causes the release of cytokines, which are chemical messengers that trigger more inflammation and destruction. This battle between the body's chemicals occurs mainly in the joints, but it can spresd to other areas of the body.

There are many cytokines, but the most important in terms of causing inflammation are tumor necrosis factor (TNF) and interleukin-1. These cytokines are thought to trigger other parts of the immune system in rheumatoid arthritis. Medicines that block TNF, interleukin-1, and interleukin-6 can improve the symptoms and prevent joint damage in rheumatoid arthritis.

What Is Psoriatic Arthritis?

Psoriatic arthritis is a chronic disease characterized by inflammation of the skin (psoriasis) and joints (arthritis). With psoriasis, there are patchy, raised, red, and white areas of skin inflammation with scaling. Psoriasis usually affects the tips of the elbows and knees, the scalp, the navel, and skin around the genital areas or anus.

About 10% of people with psoriasis also develop an associated inflammation of their joints called psoriatic arthritis. Psoriatic arthritis can cause a sausage-like swelling of fingers and toes and is often associated with fingernails that are pitted or discolored. In some people with psoriatic arthritis, only one joint or a few joints are affected. For example, a person may be affected in only one knee. Sometimes the spine is affected, or just the fingers and toes.

Psoriatic arthritis usually strikes around the age of 30 to 50, affecting both men and women equally. But it can also start in childhood. The skin disease (psoriasis) and the joint disease (arthritis) often appear separately. In fact, the skin disease precedes the arthritis in nearly 80% of patients. The arthritis may precede the psoriasis in up to 15% of patients.

Rheumatoid Arthritis Health Center

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