The Most Common Types of Arthritis, and Who’s at Risk for Each
More than 100 conditions involve inflammation of the joints.
If you’ve been feeling extra stiff lately, you may wonder if you have arthritis—a condition in which one or more of your joints is inflamed. About 54 million Americans experience some type of arthritis, but there are actually more than 100 joint-related conditions that may fall under this general umbrella.
While some types of arthritis can be genetic, other risk factors for developing arthritis include age, gender (women are more likely to have certain types of arthritis, while men are more likely to have others), a previous joint injury, and obesity. Here are the three most common forms of arthritis, how to tell the difference, and the ways health-care providers will treat it.
Also known as "wear and tear" arthritis, osteoarthritis is the most common form of arthritis. It causes cartilage—the tissue that covers the ends of bones where they form a joint—to break down to the point at which bone grinds against bone, leading to pain and stiffness. Osteoarthritis generally appears in the knees, hips, feet and spine, and can either evolve over many years or be prompted by an injury or infection.
RELATED: 13 Natural Remedies for Arthritis
People who have osteoarthritis experience pain, decreased range of motion, aches, pain when walking, and a feeling of stiffness that sets in after you’ve rested. Sometimes, joints like the knees even emit creaky sounds when bent.
With this form of arthritis, symptoms typically come and go. “Osteoarthritis joint pain is worse in the morning, and improves with activity as the day goes on,” says Stella Bard, MD, a rheumatologist in New York City.
If you have osteoarthritis, your healthcare provider will want you to manage your weight and stay active, which can help support and maintain the structures around the joint, says Lisa Gale Suter, MD, a Yale Medicine rheumatologist. Physical therapy can also be helpful in teaching exercises that will help keep the muscle around that arthritic joint strong.
“If it’s your knee that’s painful, for example, you will want to be sure your quad and hamstring muscles are healthy and strong,” says Dr. Suter, “and that you have flexibility in those muscles so that the tendons and ligaments can work.” In addition, patients often take anti-inflammatory medications (such as over-the-counter pain relievers) to ease symptoms.
This common forms of arthritis is actually an autoimmune disorder. That means that the body’s immune system is targeting the lining of the joints—which, in turn, prompts inflammation in the part of the joint that protects and lubricates. Once it becomes inflamed, pain and swelling occur.
Rheumatoid arthritis (RA) causes joint pain and swelling, especially in the knuckles, heels, or elbows. It also causes skin lumps, known as rheumatoid nodules, and stiffness that can last for hours or days.
After a diagnosis of RA, people may be prescribed oral medications or injections to manage their symptoms. These drugs can include corticosteroids (such as prednisone), DMARDs (an acronym for disease-modifying anti rheumatic drugs), and biologic injections to control the inflammation.
“We recommend powerful anti-inflammatories that work to change the inflammation pathways,” Dr. Suter says. But she adds one caution: “These medications carry a risk of lowering your immunity, so patients have to be particularly vigilant about infections and may need to stop medications if they become ill.”
While the cause of psoriatic arthritis is not entirely clear, experts do know that it’s also an autoimmune disease that manifests in similar ways to rheumatic arthritis. The main difference is that when you have psoriatic arthritis, the skin can be involved, as well.
Between 5% and 20% of psoriasis patients will also have psoriatic arthritis. “Some patients can have it with a lot of skin disease, where the body is very covered in rashes, while others have more joint symptoms and no active skin disease,” Dr. Suter says.
Symptoms of psoriatic arthritis include pain, swelling, redness in the joints (especially in the hands), nail changes, fatigue, eye problems, skin rashes, and swelling and tenderness in fingers and feet.
To control inflammation, psoriatic arthritis patients will take similar medications as those who have RA. These include NSAIDs, DMARDs, biologics, as well as new oral treatments.
Other forms of arthritis
While osteoarthritis, RA, and psoriatic arthritis tend to be the most common forms of arthritis, there’s a long list of other types of arthritis. These include bursitis, carpal tunnel syndrome, gout, Raynaud’s phenomenon, and ankylosing spondylitis, according to the Arthritis Foundation. Other conditions—such as Lyme disease, lupus, fibromyalgia, and inflammatory bowel disease—can also include arthritis as one component of a more complex illness.
Arthritis usually occurs in adults, and advanced age is a risk factor for many different types. But children can also get a rare type of arthritis known as childhood or juvenile arthritis.
Because inflammation of the joints can be caused by so many different conditions, it’s important to see a doctor if you’re experiencing pain and stiffness. A primary-care physician is a good first step, or you may be referred to a rheumatologist who can help diagnose and treat your specific joint problems.
To get our top stories delivered to your inbox, sign up for the Healthy Living newsletter