Rheumatoid arthritis of the knee
Rheumatoid arthritis of the knee causes the joints to become tender or painful, stiff, warm and swollen.
Normally, a small pouch covered with a thin tissue called synovium lies between the two pieces of joint cartilage. Cartilage is a material that covers the ends of joint bones. Cartilage helps to keep bones from rubbing against each other during movement.
The synovium secretes a liquid. This liquid helps keep joints lubricated. When joints are well lubricated, they move smoothly and painlessly. Inflammation of the synovium leads to damage and permanent destruction of the joint.
What are the signs and symptoms of knee rheumatoid arthritis?
With knee rheumatoid arthritis, you may feel the following:
- Swelling, inflammation
- Warmth around the knee joints
- Flu-like symptoms
What causes knee rheumatoid arthritis?
The actual causes of rheumatoid arthritis are not understood. It is known that rheumatoid arthritis occurs when the body's immune system doesn't function properly.
Rheumatoid arthritis may be linked to genetics. Environmental factors also may be involved, but experts are unsure of the exact cause.
How is knee rheumatoid arthritis diagnosed?
Your GP can diagnose knee rheumatoid arthritis. He or she will do a physical examination, talk to you about your personal and family medical history and arrange blood tests.
- Blood tests for rheumatoid arthritis may be positive for the following:
- Anaemia (low red blood cell count)
- Rheumatoid factor (RF), found in about 70% to 80% of those with rheumatoid arthritis
- High erythrocyte sedimentation rate (ESR), which indicates inflammation
- Antibodies to cyclic citrullinated peptides (CCP)
- High levels of C-reactive protein (CRP)
Your doctor may arrange an X-ray of the joints. An MRI scan may also be used to detect evidence of joint damage or destruction.
You may have a sample of joint fluid (synovial fluid) taken to analyse. People with rheumatoid arthritis usually have joint fluid that's filled with inflammatory material.
What's the treatment for knee rheumatoid arthritis?
The best treatment for knee rheumatoid arthritis is early and intensive medical care. Medical treatments include the use of disease-modifying anti-rheumatic drugs (DMARDs), which are used with NSAIDs (non steroidal anti-inflammatory drugs) and/or steroids in low doses.
Some of the most commonly prescribed DMARDs include sulfasalazine, methotrexate, leflunomide and hydroxychloroquine.
Tumour necrosis factor (TNF) blockers are a more recent type of DMARD prescribed to ease symptoms more quickly. They include infliximab, etanercept, certolixumab, tocilizumab, rituximab and adalimomab.
Other treatments are:
- Nonsteroidal anti-inflammatory drugs (NSAIDs) -- over-the-counter and prescription strength
Along with early and intensive medical therapy, regular exercise is important. Exercise helps strengthen the muscles around the knee and helps support the joint. Sometimes physiotherapy and occupational therapy are recommended.
Is surgery necessary for knee RA?
At some point, total joint replacement may be performed. This operation is usually a "last resort" instead of the first treatment option for knee rheumatoid arthritis. Today's advances in total joint replacement give a successful outcome in most cases.
Synovectomy is another procedure that's performed in rheumatoid arthritis. With synovectomy, the surgeon removes the inflamed synovium or joint lining. Synovectomy can be done as an open procedure or by arthroscopy. In general, arthroscopic procedures are associated with fewer complications and faster recovery than more invasive surgery. The relief in knee pain with synovectomy in rheumatoid arthritis may last up to five years or more.