The knee is the intersection of the femur and tibia bones. This hinge joint, which is able to swivel in two directions, is an important load-bearing joint and is protected and cushioned by a layer of cartilage and synovial fluid. Arthritis can cause damage to a knee joint, resulting in pain and stiffness.
Arthritis Types
The American Association of Orthopedic Surgeons explains that there are three kinds of arthritis that can cause knee pain. Osteoarthritis is caused by the protective cartilage in the knee gradually wearing away. Rheumatoid arthritis is caused by the immune system attacking the tissue within the knee joint. Post-traumatic arthritis is the result of an injury to the knee resulting in destruction of the knee's cartilage.
Osteoarthritis
As the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) explains, osteoarthritis commonly afflicts the knees. Patients with osteoarthritis develop pain and stiffness in joints when they have been sitting or resting for an extended period of time. Patients may also hear a crunching or grinding sound from their knees as a result of bone-on-bone contact. Osteoarthritis typically affects older people and people who put extra stress on their knees, such as runners and the obese.
Rheumatoid Arthritis
Rhuematoid arthritis is another form of arthritis that can affect the knees. Rheumatoid arthritis is an auto-immune condition and typically affects patients earlier in life. FamilyDoctor.org explains that because rheumatoid arthritis is caused by the immune system attacking the joints, multiple joints in the body are usually affected. Smaller joints, such as the fingers, wrist and the knees are typically the first joints to be damaged. Patients with rheumatoid arthritis often experience a fever and deformity of the joints as a result of the chronic inflammation.
Conservative Treatments
Both of the major forms of knee arthritis (osteoarthritis and rhuematoid) are commonly treated with non-steroidal anti-inflammatory medications (such as ibuprofen, naproxen and aspirin). These medications can help reduce swelling and relieve pain. Patients also may be instructed to ice their knees frequently and to engage in a physical therapy program to keep the muscles around the injured joints strong. Rheumatoid arthritis is commonly treated with prescription corticosteroids (such as prednisone). These medications suppress the immune system and can relieve the swelling. Corticosteroids can also be injected directly into the knees to relieve pain and swelling for both osteoarthritis and rheumatoid arthritis.
Surgery
The American Association of Orthopedic Surgeons notes that arthritis of the knee can also be treated surgically. One procedure--arthroscopy--uses a small flexible camera which is inserted through small incisions into the knee. This allows the surgeon to see the damaged joint and remove and damaged cartilage or inflamed tissue. An osteotomy cuts and reshapes the tibia (lower leg) and femur (thigh bone) to make the knee align better. Finally, a total knee replacement may be necessary for extreme cases, in which the damaged knee is replaced with a prosthetic joint.
