Top 3 Types of Arthritis

Did you know that there are more than 100 types of arthritis? Learn about the three most common ones, including what they are, what happens, and their symptoms.


What it is: More people have this condition than any other form of arthritis. It's the "wear and tear" that happens when your joints are overused. It usually happens with age, but it can also come from joint injuries or obesity, which puts extra stress on your joints.


Joints that bear weight -- such as your knees, hips, feet, and spine -- are the most common places it affects. It often comes on gradually over months or years. It makes the affected joint hurt. But you don’t feel sick or have the fatigue that comes with some other types of arthritis.


What happens: You lose your body's shock absorber. Cartilage, the slippery material that covers the ends of bones, gradually breaks down.


One example is what can happen to your knees when you're overweight. The extra pounds put more pressure on the cartilage as it gets squeezed between the bones. It gets damaged and wears away, so there isn't as much left to cushion the joint.


The damaged cartilage makes movement painful. You may hear a grating sound when the roughened cartilage on the surface of the bones rubs together. You may get painful spurs or bumps on the end of the bones, especially on fingers and feet. The joint lining can get inflamed, but it's not common with osteoarthritis.


Symptoms depend on which joint or joints are affected. You may have:


  • Deep, aching pain
  • Trouble dressing, combing hair, gripping things, bending over, squatting, or climbing stairs. depending on which joints are involved
  • Morning stiffness that typically lasts less than 30 minutes
  • Pain when walking
  • Stiffness after resting


Your joint may be:


  • Warm to the touch
  • Swollen and harder to move
  • Unable to move through a full range of motion



Rheumatoid Arthritis

What it is: RA is an autoimmune disease. That means the immune system attacks parts of the body, especially the joints. That leads to inflammation, which can cause severe joint damage if you don't treat it. About 1 out of every 5 people who have rheumatoid arthritis get lumps on their skin called rheumatoid nodules. These often form over joint areas that receive pressure, such as over knuckles, elbows, or heels.


What happens: Doctors don't know exactly what causes RA. Some experts believe the immune system becomes "confused" after infection with a bacteria or virus and starts to attack your joints. This battle can spread to other areas of the body.

Scientists think two of the body's chemicals that are related to inflammation, tumor necrosis factor (TNF) and interleukin-1, 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.

Symptoms can come on gradually or start suddenly. They're often more severe than with osteoarthritis.

You may feel pain and stiffness and have swelling in your hands, wrists, elbows, shoulders, knees, ankles, feet, jaw, and neck. Rheumatoid arthritis usually affects multiple joints.

There tends to be a symmetrical pattern, too. When the knuckles on your left hand are inflamed, the knuckles on your right hand probably will be as well. After some time, you may notice more of your joints feel warm or become painful or swollen.

The joint swelling doesn't go away. It gets in the way of things like opening a jar, driving, working, walking, and other activities of daily living.

The stiffness that usually starts in the morning may later last for hours or even most of the day. You may also feel fatigued and notice that your appetite is down and you've lost weight. RA can also affect other organs including the heart, lungs, and eyes.

Psoriatic Arthritis

What it is: People with this condition have inflammation of the skin (psoriasis) and joints (arthritis).


Psoriasis causes patchy, raised, red, and white areas of inflamed skin with scales. It usually affects the tips of the elbows and knees, the scalp, the navel, and skin around the genital areas or anus.


Only about 10% to 30% of people with psoriasis will also get psoriatic arthritis.


What happens: This type of arthritis usually starts between ages 30 and 50, but it can start as early as childhood. It's equally common among men and women. The skin disease (psoriasis) usually shows up first.


Symptoms:Psoriatic arthritis can swell the fingers and toes. People who have it often have fingernails that are pitted or discolored, too.


In some people, only one joint or a few joints are affected. For example, you could have it in only one knee. Sometimes it affects the spine or just the fingers and toes.

WebMD Medical Reference Reviewed by Nayana Ambardekar, MD on November 21, 2017




National Institute of Arthritis and Musculoskeletal and Skin Diseases: "Arthritis."


The Arthritis Society: "An Introduction to Arthritis."


Arthritis Foundation: "Frequently Asked Questions About Osteoarthritis."


American College of Rheumatology: "Rheumatoid Arthritis."


McIlwain, H., MD and Bruce, D., PhD. A Diet for a Pain-Free Life, Marlowe, 2007.

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