Like all joints, your knees are affected by rheumatoid arthritis, but many treatments are available to help easy your symptoms.
Rheumatoid arthritis (RA) is a type of arthritis where your immune system attacks healthy tissues in your joints.
RA primarily affects the joints in your hands and feet, but your knees and other joints can also be involved. RA is often symmetrical as well. For example, this means both of your knees would be affected.
More than 1.3 million Americans have RA. But your knees may not show signs of RA until much later, even years after symptoms begin to appear.
Untreated RA can cause long-term and progressive inflammation that can ultimately lead to joint damage.
Let’s look into how RA can affect your knees, how to recognize the symptoms, and how you can get RA diagnosed and treated before it causes damage.
In RA, your immune system attacks and damages the synovial cell lining of your joint. The synovial cell is the connective tissue that lines your joints. RA causes your synovial cells to increase, which causes thickening and inflammation. It’s the same with RA in your knees:
- Immune cells target the synovial membrane that lines your knee joint. This membrane protects the cartilage, ligaments, and other tissues of your knee joint. Synovial cells also produce synovial fluid, which lubricates your joints, further allowing smooth movement.
- Your joint becomes inflamed, which causes pain and damage to your joint tissue. Your knee movement is also limited as the swollen membrane takes up more space in the knee area.
Over time, the inflammation can damage the cartilage and ligaments of your knee joints. Along with synovial fluid, these help your knees move and keep your bones from grinding against each other.
As they become damaged, your cartilage wears away and exposes your bone. Bone, unlike cartilage, has pain receptors. As your bone is exposed, your bones start to push and grind against each other. This results in pain and bone damage.
Tissue damage from RA can led to chronic, or lasting, pain, affect your balance and steadiness, and change the appearance of your joints.
A hallmark symptom of RA is tenderness, pain, or joint discomfort that worsens when you stand, walk, or exercise. This is known as a flare. It can range from a mild, throbbing pain to intense, sharp pain.
More common symptoms of RA in your knees
- warmth around your joint
- stiffness or locking of your joint, especially during cold weather or in the morning
- weakness or instability of your joint when you put weight on it
- difficulty moving or straightening your knee joint
- creaking, clicking, or popping noises when you move your joint
Other symptoms of RA you might experience can include:
- dry mouth and eyes, which can be a symptom of Sjögren’s disease
- eye inflammation, such as uveitis (affecting the middle of your eye) or iritis (affecting your iris)
- losing your appetite
- abnormal weight loss
- neuropathy, or tingling or numbness in your feet or fingers
- shortness of breath and dry, chronic cough, which can be a symptom of interstitial lung disease
Here are a few of the methods a doctor or healthcare professional may use to diagnose RA in your knees:
In a physical exam, a doctor may have you sit, and they observe your leg as you extend it. They may place a hand on your knee to feel the joint grinding (crepitus) and friction in your tendons and ligaments.
A doctor may ask you to put weight on your joint and listen for grinding or other unusual noises.
They may also ask general questions about your symptoms, overall health, and medical history.
C-reactive protein or erythrocyte sedimentation rate tests measure the levels of proteins that are increased with inflammation in your body and can help diagnose RA.
A doctor may use imaging tests to get a better look at your joint:
- Ultrasounds can show the fluid in your knee and inflammation. Occasionally, they may be used to guide fluid drainage in difficult cases.
- X-rays can show overall damage, abnormalities, or changes in the shape and size of your joint and joint space.
- MRIs provide detailed, three-dimensional (3-D) images that can confirm damage to your bones or tissues in your joint.
Depending on the severity and progression of RA in your knee, you may only need over-the-counter (OTC) medications.
For advanced RA, you may need surgery to restore your mobility or lower the pain and stiffness in your knee joint.
Treatments for RA that don’t require surgery can include:
- Corticosteroids: A doctor injects corticosteroids into your knee joint to help lower swelling and pain. These injections are only temporary. You may need to get them regularly, usually a few times per year as needed.
- Nonsteroidal anti-inflammatory drugs (NSAIDs): OTC NSAIDs, such as naproxen (Aleve) or ibuprofen (Advil), can lower pain and inflammation. They’re available at almost any drug or grocery store.
- Topical analgesic medications: These creams and gels are applied to your skin to help relieve pain from arthritis. They may include medications such as OTC diclofenac topical gel (Voltaren Arthritis Pain) or prescription diclofenac topical solution (Pennsaid).
- Disease-modifying antirheumatic drugs (DMARDs): DMARDs lower inflammation, making your symptoms less severe and slowing down the progression of RA over time. The DMARD methotrexate [Otrexup (PF), Xatmep, and Trexall] is considered a first-line treatment.
- Janus kinase (JAK) inhibitors: The Food and Drug Administration (FDA) has approved the JAK inhibitors tofacitinib (Xeljanz), upadacitinib (Rinvoq), and baricitinib (Olumiant) for RA. These are oral pills that inhibit the activity of JAK enzymes to prevent the immune response.
- Biologics: Biologics are more targeted in their effect on your immune pathways and inflammation than DMARDs. They lower your immune system response to reduce RA symptoms. Common biologics include adalimumab (Humira) and tocilizumab (Actemra).
Surgical options for RA include:
- Repairing damaged ligaments or tendons: This can strengthen your knee joint and reverse damage from inflammation.
- Reshaping your knee bones or joint tissue (osteotomy): This can lower pain from loss of cartilage and grinding of your knee bone.
- Replacing your knee joint: Replacing your joint with an artificial plastic or metal prosthetic joint can restore strength and mobility.
- Removing the synovial membrane (synovectomy): This removal from around your knee joint was a method used to lower pain from swelling and movement, but it’s rarely done today.
Here are some other strategies and remedies you can try to reduce the symptoms of RA in your knees:
- Exercise tips: Try low impact exercises such as swimming or tai chi to take pressure off your knees. Exercise for shorter periods of time to lower the chance of a flare up. Joint support and bracing can add stability and prevent injury.
- Dietary changes: Try an anti-inflammatory diet or natural supplements such as fish oil or turmeric to reduce symptoms.
- Home remedies: Put a warm compress on your joint to help restore some mobility and relieve swelling, especially in combination with an NSAID or other OTC pain reliever such as acetaminophen.
- Assistive devices: Try customized shoe inserts or insoles. You can also use a cane or wear knee braces to lower the pressure on your knee joints to make it easier to walk.
Schedule an appointment with a doctor if you experience any of the following related to your knee joints:
- inability to walk or do your usual daily activities due to joint pain or stiffness
- intense pain that keeps you up at night or affects your overall mood or perspective
- symptoms that interfere with your quality of life, such as keeping you from doing your favorite hobbies or seeing friends and family
Get immediate medical care if you experience significant knee swelling or hot, painful joints. This may suggest an underlying infection that can lead to joint destruction.
RA can affect your knees just like any other joint in your body and cause pain, stiffness, and swelling that can get in the way of your everyday life.
The key is to get treatment early and often. Your joint can become damaged over time and limit your movement, making it hard to walk or stand.
Talk with a doctor if the pain is interfering with your quality of life and making it hard to do basic tasks that involve your knees.