RA in the knees can seriously affect a person’s mobility. RA typically affects the joints of the hands, wrists, and knees, causing inflammation and deterioration of the lining of the joints. RA is usually symmetrical, affecting both sides of the body equally. Affected individuals may find it difficult to carry out daily activities, and if RA affects their knees, they may have trouble walking, climbing stairs, and moving around in general. If people do not seek treatment for RA, it can cause progressive inflammation, leading to joint damage that can ultimately lead to permanent disability.
In this article, we explain how RA affects the knees, and we outline the symptoms and treatment options.
How arthritis affects the knees
The knees are the largest and strongest joints in the body. The knee is made up of the patella, the lower end of the femur and the upper end of the tibia. The ends of these bones form the knee joint. The protective cartilage that cushions the bone as the knee bends and straightens covers the ends of the bones. A thin capsule of tissue called the synovial membrane lines the joint. The role of this membrane is to release a lubricating liquid that reduces friction and protects cartilage and ligaments.
If RA affects the knees, the immune system mistakenly targets the synovial membrane. This reaction causes inflammation and painful swelling due to the proliferation, or growth, of cells. The swelling of the synovial membrane then limits movement. RA usually affects the knees on both sides equally.
As the disease progresses, the swelling damages the cartilage and ligaments, which can no longer cushion friction. The cartilage then wears away, leading to bone damage.
Sometimes the bones can fuse together, which doctors call ankylosis. Ankylosis affects about 0.8% of people with RA. People with RA can sustain significant damage, which can leave them with debilitating, life-altering symptoms.
Symptoms of knee arthritis
People with RA experience periods when their symptoms worsen, called flare-ups, or improve, called remission. In general, the knees gradually become more painful and inflamed. However, some people may experience sudden and intermittent symptoms.
If a person has RA in the knees, they may experience symptoms such as:
– stiff and swollen joints, difficult to bend and straighten
– pain and swelling, which may get worse after periods of rest
– pain that increases with vigorous physical activity
– sudden blockage during a movement
– creaking, rattling, popping or squeaking noises
– a feeling of weakness or buckling of the knee.
Other generalized symptoms of RA include:
– fatigue or exhaustion
– low fever
– inflamed, dry eyes and dry mouth
– low blood cell count
– nodules or bumps under the skin above bony areas.
How can RA affect a person?
RA can potentially change a person’s life due to reduced mobility and physical weakness. Stiffness and pain in the knees can make it difficult to get out of bed, bathe, and get dressed. Also, regular daily activities can become extremely difficult as the disease progresses and causes further damage. Therefore, some people need support in all aspects of their lives.
The unpredictability of symptoms makes activities difficult to plan and can make people with RA feel like they have lost control of their lives. This is why many people with RA feel depressed and anxious. Additionally, a number of people with RA experience extreme fatigue, which leaves them feeling excessively tired. Fatigue increases the need for sleep and makes the simplest activities excessively demanding. RA can alter relationships because people can no longer participate in old hobbies and interests. As people lose mobility and feel increasingly tired, they may avoid taking part in strenuous social activities and spending quality time with others.
Also, RA can impact a person’s job because they are no longer able to function as before. For example, in a 2002 study, researchers note that approximately 1 in 3 people with RA quit their job within 5 years of being diagnosed with RA.
Doctors use a combination of medical history, physical exam, and lab tests to diagnose RA of the knees:
– Medical history: A doctor will ask about joint symptoms, including when they started, their severity, and what makes them better or worse, and ask if any relatives have RA or other autoimmune diseases .
– Physical exam: The doctor will look for signs of tenderness, swelling, warmth, or limitation of movement in the knees and joints. He will also check for a mild fever and bumps under the skin.
– Blood tests: These tests identify inflammatory markers, such as erythrocyte sedimentation rate and C-reactive protein. The tests also look for rheumatoid factor (RF), an antibody present in 80% of people with RA, or cyclic citrullinated peptide (CCP), which is present in 60-70% of people with the condition.
– Imaging tests: Because RA can damage joints, doctors may use X-rays, ultrasounds, or MRIs to identify bone and joint erosion. However, images may not help doctors diagnose RA in the early stages, when bone damage is minimal.
Depending on the severity of RA in the knee joints, a person may only need over-the-counter nonsteroidal anti-inflammatory drugs to relieve pain and inflammation. A doctor may also prescribe corticosteroids.
Disease-modifying antirheumatics are a class of drugs that reduce inflammation and symptom severity and slow the progression of RA. Other options include hydroxychloroquine (Plaquenil) and sulfasalazine (Azulfidine).
For people with significant knee damage, a doctor may recommend knee replacement surgery to allow them to return to their usual daily activities.
When to contact a doctor
A person should see a doctor if they experience pain, stiffness, or swelling in their knees or other joints. Likewise, people should seek advice if they have other symptoms of RA. A doctor can make an accurate diagnosis, rule out any other problems, and recommend appropriate treatment.
In general, people are diagnosed within 6 months of the onset of their symptoms. This allows them to start a treatment regimen that minimizes bone destruction and the impact of RA on their lives. If a person experiences pain and swelling in the knee joint, as well as fever, tremors, and chills, they should seek medical attention immediately. These symptoms could indicate a serious infection, which requires emergency treatment.
Support for people with RA
Being diagnosed with RA can make you feel overwhelmed and lonely. If possible, they should find emotional and physical support from family and friends to learn to live with a chronic illness. Affected people may also find it helpful to connect with other people living with RA and learn from their experiences.
RA is an autoimmune disease that affects the joints, especially the knees. It causes pain, stiffness and swelling that can disrupt a person’s life, making it difficult to walk or stand. People should see a doctor if they notice signs of RA or have symptoms in the knee. People should start treatment as soon as possible to prevent damage to knees and joints that can be disabling.