Rheumatoid arthritis (RA) and osteoarthritis (OA) have a number of differences, such as onset, length of development, the types of joints affected, and treatment options. However, there are some similarities in symptoms, as they both involve joint pain.

Arthritis is an umbrella term used to describe inflammation of the joints. There are different kinds of arthritis, including rheumatoid arthritis (RA) and osteoarthritis (OA).

Although RA and OA both affect your joints, they’re very different forms of arthritis. Keep reading to learn more about RA and OA.

Rheumatoid arthritisOsteoarthritis
When it startsAny age.Usually later in life.
How it developsFairly quickly, over weeks or months.Slowly over many years.
Risk factorsCan run in families. RA is 2–3 times more common in women.Overweight and obesity, joint deformities, traumatic joint injuries, diabetes, and gout. It’s more common in men under age 45 and women older than 45.
SymptomsIn addition to joint pain and swelling, you may have a low-grade fever, muscle aches, and fatigue. RA can affect your entire body, including your heart and lungs. In advanced cases, hard lumps called rheumatoid nodules may develop under the skin near joints.Mostly limited to joint pain. Excessive bone growths, called Heberdens and Bouchards nodes, may develop on the small finger joints.
Joints affectedUsually begins in smaller joints, especially in the fingers. Symptoms are symmetrical (on both sides of the body) and may later develop in larger joints.Often joints in the hands and fingers, but less symmetrical than RA. Also affects the knees, spine, and hips.
TreatmentDisease-modifying medications and biologics that target your immune system.Anti-inflammatory medications and intra-articular steroid injections

RA is an autoimmune disorder, which means your body begins to attack itself. If you have RA, your body interprets the soft lining around your joints as a threat, similar to a virus or bacteria, and attacks it.

This attack causes fluid to accumulate within your joint, which is produced by the inflamed tissue. The swelling and fluid buildup also causes:

  • pain
  • stiffness
  • inflammation around your joints
  • decrease joint flexibility

OA, the most common form of arthritis, is primarily a degenerative joint disorder.

People with OA experience a breakdown of the cartilage that cushions their joints. The wearing down of cartilage causes the bones to rub against each other. This exposes small nerves, causing pain.

OA doesn’t involve an autoimmune process like RA does, but inflammation can still occur.

“Fatigue was my first major symptom. They did all sorts of tests, including testing my thyroid. Then, they suggested an HIV test. When joint pain started, they thought it was a blood clot in my knee. Finally, I was referred to a rheumatologist.” —Anonymous, living with rheumatoid arthritis

Both types of arthritis are more common in women than in men. RA and OA are more common in older adultsTrusted Source, but RA can develop at any age.

RA can run in families. You have a higher chance of developing the condition if a parent, child, or sibling has it.

Many of the basic symptoms of RA and OA are the same, including:

Characteristics of RA

Each kind of arthritis also has its own unique set of symptoms. RA is a systemic disease, which means it can affect your entire body — lungs, heart, eyes — and not just your joints. Early signs of RA can include:

People with advanced stages of RA may notice hard lumps underneath the skin near joints. The lumps, called rheumatoid nodules, can be tender.

Characteristics of OA

People with OA are unlikely to experience systemic symptoms. The degenerative nature of OA is limited to the affected joints.

You might develop lumps under the skin around joints, but these lumps are different from rheumatoid nodules. People with OA tend to develop Heberdens and Bouchards nodes, or excess bone growth in the fingers.

RA and OA may affect different joints.

Affected joints in RA

RA usually beginsTrusted Source in the smaller joints. You’re likely to have pain, stiffness, and swelling in the finger joints. As RA progresses, symptoms can develop in larger jointsTrusted Source such as knees, shoulders, and ankles.

RA is a symmetrical disease. This means you may experience symptoms on both sides of your body at the same time.

Affected joints in OA

OA is less symmetrical. You might have pain in both your left and right knee, for example, but one side or one joint is worse.

OA, like RA, is common in the hand and fingers. OA often affects the spine and hips in addition to the knees.

The primary goal in treating both OA and RA is to:

  • reduce pain
  • improve function
  • minimize damage to your joints

Your doctor will approach these goals differently, depending on which condition you have.

Anti-inflammatory medications are generally effective for both OA and RA.

Oral steroids can be used temporarily at low doses during RA flares. Intra-articular steroids can be used for OA. Keep in mind that the use of corticosteroids in both RA and OA is minimized due to severe side effects.

If you have RA, drugs that suppress your immune system can prevent damage by stopping your body from attacking your joints, and prevent joint damage.

Although they’re different forms of arthritis, both RA and OA affect your joints. Treatments are available to help reduce the symptoms of both conditions.

Contact your doctor if you think you’re experiencing symptoms of RA or OA. If needed, they can refer you to a specialist who can help you find the right treatment to manage your condition.