Knee Inflammation, Swelling, and Stiffness

In most cases, knee pain, swelling, and inflammation develop in the later stages of rheumatoid arthritis (RA). The knee is the largest and strongest joint in the body. When it becomes affected by RA, you may have trouble doing everyday activities like walking and climbing stairs.^1,2

Since RA in the knee can greatly impact mobility and quality of life, the sooner treatment is started, the greater chance that joint damage can be reduced or prevented.

How does RA affect the knee?

The knees are formed where the bones of the lower and upper leg bones meet. It includes 3 bones:³

• Femur (upper leg bone, or thigh bone)
• Tibia (bone at the front of the lower leg, or shin bone)
• Patella (kneecap)

Two large pieces of cartilage called the meniscus work to absorb shock between the femur and tibia and keep the joint stable. The knee joint is surrounded by the synovium, a thin membrane that cushions the joints and releases a fluid that makes it easier for your joints to move. This is called synovial fluid.^2,3

In people with RA, the body’s immune system attacks the synovium and healthy tissues inside the joints. This causes an inflammatory response that results in swelling, stiffness, and pain, especially when the joint is used. Other common symptoms of RA in the knee joints include:²

• Pain or swelling that is worse in the morning, or after sitting or resting
• Pain that is worse after intense activity
• Knees that lock or stick during movement
• Knees that creak, click, snap, or making grinding noises
• Feelings of weakness or buckling in the knee

Some people also develop a Baker’s cyst (fluid-filled sac) in the hollow space at the back of the knee. In some cases, the cyst may rupture and extend down the calf.^1,2

RA is sometimes symmetrical, which means it usually affects the same joints on both sides of the body. As the condition gets worse, ligaments, joints, and cartilage become more damaged. This can lead to significant disability.^4,5

There are periods of time when RA symptoms become worse, known as flare-ups or flares. These flares are then followed by periods when symptoms decrease.

The exact cause of RA is not known. Doctors believe that some people have genes that make them more likely to develop RA. However, this does not mean that people with these genes always develop RA. There is usually something that triggers the condition, like an infection. This causes the immune system to start attacking the joints.^4,5

How is RA knee pain treated?

While there is no cure for RA, there are different ways you can manage the inflammation, pain, and stiffness that affect your knees. Treatment depends on your symptoms and how severe they are. The goals of RA treatments include:^1,6

• Stop or reduce inflammation
• Relieve symptoms
• Prevent joint and organ damage
• Improve function and well-being
• Reduce long-term complications

Nonsurgical and surgical options are available to treat RA knee pain, swelling, and inflammation.

Nonsurgical treatments for RA knee pain

In most cases, the first treatment approach includes nonsurgical options like lifestyle changes and medicines. They can help reduce your symptoms and help them from getting worse. The options may include:²

• Limiting or stopping activities that make your wrist pain worse, like climbing stairs
• Switching to low-impact exercises like biking and swimming, which can help you stay healthy while reducing the impact on your knees
• Losing weight, which can reduce stress on the knee joints
• Wearing a knee brace to help support your joints and ease the stress placed on them
• Taking nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen to help reduce pain and inflammation. Topical NSAIDs (medicine applied directly to the skin) can also be applied in the areas of the joints.
• Doing exercises that help improve the range of motion and function in your knees. Your doctor may have you work with a physical therapist to find exercises that work best for you.
• Getting steroid injections into your knee joints can help reduce inflammation
• Applying ice or heat to your knees to help reduce pain and swelling
• Using assistive devices to reduce stress on the joints, like a cane or impact-absorbing shoes/inserts

If none of these options control your RA symptoms, your doctor may prescribe disease-modifying anti-rheumatic drugs (DMARDs). These are drugs that are designed to stop the immune system from attacking the joints. This slows or prevents joint deformity. There are both benefits and risks of DMARDs, so talk to your doctor about whether these drugs are right for you.⁷

Surgical treatments for RA knee pain

If your RA symptoms do not respond to lifestyle changes or medicines and your quality of life has been impacted by your rheumatoid arthritis, your doctor might recommend surgery. The type of surgery used depends on how severely your joints are damaged. Surgeries include:²

• Synovectomy – During this procedure, the surgeon removes the synovium, the thin membrane that lines the joints
• Osteotomy – During this procedure, either the tibia (shinbone) or femur (thighbone) is cut and reshaped to reduce pressure on the knee joint
• Total or partial knee replacement (arthroplasty) – During this procedure, a surgeon removes your damaged cartilage and bone, then positions new metal or plastic parts

Learn more about Knee surgery