Having arthritis in the knees is a common condition. There are two main types of arthritis that can affect your knees: osteoarthritis is the most common, and the other is rheumatoid arthritis. They are very different forms of arthritis and have different symptoms and treatment approaches. To help manage your symptoms, the first step is to understand the various causes of arthritis in the knee and then take steps to control the ones you can.
Wear and Tear
Osteoarthritis of the knee occurs when the cartilage in your knees begins to wear away. The result is bone rubbing on bone. This can lead to pain, stiffness and joint deformity. Some loss of cartilage is normal with age. This condition usually occurs in those who are middle age and older. It is especially common in those over age 60. However, the American Academy of Orthopaedic Surgeons states that if you participate in lot of high impact activities, your risk is higher due to the stress placed on the knee joint. Osteoarthritis can also be inherited. However, in some cases, the cause of osteoarthritis in the knee is unknown. The Arthritis Foundation cautions that being overweight also increases your risk of getting this disease. They claim, "For every pound you gain, you add three pounds of pressure on your knees and six times the pressure on your hips." Losing excess weight and switching to lower impact sports can help relieve your symptoms and reduce your chances of developing this condition.
Trauma
According to the University of California, if you suffer a knee injury such as a fracture to one of the bones in the knee, or develop a tendon or ligament problem, your knee joint may be more susceptible to developing arthritis. In addition, not exercising or using your knees enough can cause a loss of strength in the muscles that surround your knee, which can also place pressure on the joint. If the muscles become weak or tight, the cartilage may wear out faster than normal and contribute to knee arthritis.
Autoimmune Disease
You can also develop rheumatoid arthritis in your knees. Rheumatoid arthritis (RA) is an autoimmune disease, meaning the body attacks itself. In the case of RA, the destruction happens to the lining of your joints. According to the National Institute of Arthritis, Musculoskeletal and Skin Diseases, the reason this happens in some people is still not well understood. It may be genetic, the result of a viral infection or the result of abnormal levels of hormones in the body. Rheumatoid arthritis is very different from osteoarthritis. With osteoarthritis, you can have the condition in just one knee. With RA, both knees are usually involved. In addition, with RA you may have other symptoms such as fatigue and other joint involvement since it is a systemic condition.
