- How RA Affects the Knees
- Risk Factors
- Related Resources
RA is a chronic inflammatory disease in which the immune system mistakenly attacks the lining of the membrane that surrounds joints, particularly the smaller joints of the hand and wrist.
Symptoms of RA in the knees
The knee affected by RA becomes painful and inflamed. Over time, other symptoms may develop, including:
- Swelling, inflammation
- Stiffness makes it difficult to bend and straighten the knee
- Pain and swelling may be worse in the morning or after sitting or resting
- Weakness or instability of the joint
- Stiffness, especially in the morning or after sitting for long periods
- Tenderness and warmness around the knee
- Creaking, clicking, or popping noises on movement
- Fatigue, fever, and loss of appetite
Stiffness with immobility is characteristic of RA; it is usually worse in the morning and can last at least 30 minutes or more.
How does rheumatoid arthritis affect the knees?
The knee is the largest and strongest joint in the body, made up of the:
- Lower end of the femur (thighbone)
- Upper end of the tibia (shinbone)
- Patella (kneecap)
The ends of the three bones are covered with articular cartilage, a smooth and slippery substance that protects and cushions the bones during the bending and straightening of the knee.
The knee joint is also surrounded by a thin lining called the synovial membrane, which releases a fluid that lubricates the cartilage and reduces friction.
Rheumatoid arthritis is an autoimmune, chronic, and symmetrical (affects the same joint on both sides of the body) disease that causes the synovial membrane covering the knee joint to swell, resulting in pain and stiffness.
What causes rheumatoid arthritis in the knees?
Although the exact cause of rheumatoid arthritis (RA) is unknown, researchers speculate that a combination of genetic, hormonal, and environmental factors may play a key role in the development of this condition. Infection, smoking, and physical or emotional stress may also be the triggering factors.
Most joints are covered with a lining called the synovium, which lubricates the joint for easy movement.
In RA, the synovium becomes inflamed (synovitis), thickens, and produces an excess of joint fluid. This fluid along with the inflammatory chemicals released by the immune system causes swelling, damages cartilage, and softens the bone within the joint.
The swollen tissues stretch the surrounding ligaments, resulting in deformity, instability, and weakened and damaged tendons and ligaments.
What are the risk factors for rheumatoid arthritis in the knees?
Although rheumatoid arthritis (RA) can affect anyone, certain factors can make you more vulnerable to developing the condition including:
- Age (People older than 40 years are more prone to develop arthritis.)
- Gender (Women are more likely than men to develop RA.)
- A family history of RA
- Certain hereditary conditions, such as joint ligament laxity and malformed joints
- Injuries to the knee joint, such as fractures and sprains
- Activities and jobs that put extreme stress on the knee joints
How is rheumatoid arthritis in the knees diagnosed?
Unfortunately, there is no single test to diagnose rheumatoid arthritis (RA) in its early stages; a healthcare provider will examine the knee joint and may recommend certain tests:
- Blood tests: To check for
- Physical examination: To look for
- Noticeable swelling
- Redness and warmth
- Reduced range of motion
- Joint instability
- Imaging techniques: X-rays reveal signs of arthritis, including
- Bone spurs
- Worn-down cartilage
- Loss of joint space
- Other tests: An MRI or a CT scan may be needed to determine the condition of the bones and soft tissues of the knee.
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How is rheumatoid arthritis in the knees treated?
Currently, there is no permanent cure for rheumatoid arthritis, and treatment generally involves a combination of medication and therapies to curb inflammation or stop the disease progression.
- Topical medications
- Over-the-counter pain relievers
- Prescription pain relievers
- Nonsteroidal anti-inflammatory drugs
- COX-2 inhibitors
- Disease-modifying antirheumatic drugs (DMARDs) fall into three general categories
- Conventional DMARDs
- Targeted DMARDs
- Xeljanz (tofacitinib)
- Olumiant (baricitinib)
- Rinvoq (upadacitinib)
- Biological DMARDs
- Topical medications
- Injections: In case pain relievers are not effective, the doctor might recommend injecting a long-acting corticosteroid into the joint, which may provide temporary pain relief and reduce inflammation.
- Physical therapy: To help regain strength, stability, and movement
Try these home remedies to ease pain and improve joint mobility:
- Apply hot or cold fomentation to the joint for 5 to 15 minutes several times a day can help relieve swelling and pain.
- Eliminate activities that may aggravate your arthritis.
- Try strengthening and stretching exercises to reduce symptoms and improve function.
- Lose weight if you are overweight.
- Try assistive devices, such as a cane or knee braces, to lower the pressure on the knee joints.
Health Solutions From Our Sponsors
Can You Get Rheumatoid Arthritis in a Knee? WebMD: https://www.webmd.com/rheumatoid-arthritis/knee-ra-rheumatoid-arthritis-of-the-knee
Arthritis of the Knee. American Academy of Orthopedic Surgeons: https://orthoinfo.aaos.org/en/diseases--conditions/arthritis-of-the-knee/
Rheumatoid Arthritis. Cleveland Clinic: https://my.clevelandclinic.org/health/diseases/4924-rheumatoid-arthritis
What is rheumatoid arthritis? Versus Arthritis: https://www.versusarthritis.org/about-arthritis/conditions/rheumatoid-arthritis/
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