Arthritis is inflammation in the joints or area of the body where two bones come together. The one part of the body that is most affected by arthritis is the knee. There are three different types of arthritis that can occur in the knees: These include osteoarthritis, rheumatoid arthritis and post-traumatic arthritis.
Osteoarthritis is the most common form of knee arthritis. Osteoarthritis develops due to wear and tear of the natural cushioning (cartilage) between joints. When joint cartilage gradually wears away, the bones of the joints rub more closely against one another with less of the shock-absorbing benefits of cartilage. The rubbing results in pain, swelling, stiffness, reduced ability to move and, sometimes, the formation of bone spurs. It is usually a slowly progressive degenerative disease and most often affects middle-aged and older people. It can also affect younger people, particularly where they have had joint injury or surgery.
Rheumatoid arthritis is a systemic inflammatory disease of the immune system. It affects multiple joints in the upper and well as the lower limbs. Knees are one of the common joints affected by RA, occurring at any age and potentially affecting both knees. It affects the knee joint synovium that lines the ends of the bones and produces an excess of joint fluid. The excess synovial fluid, together with inflammatory chemicals that the immune system releases, leads to swelling and damage to the cartilage, causing joint pain.
Post-traumatic arthritis is a common form of osteoarthritis that is caused by a previous injury or other form of trauma. It can occur years after a torn meniscus, injury to ligament or fracture of the knee.
Knee Arthritis Symptoms
The symptoms of knee arthritis most commonly include pain and stiffness of the affected joints. Generally, the pain associated with arthritis develops gradually, although sudden onset is also possible. The joint may become stiff and swollen, making it difficult to bend or straighten the knee. The pain is more often than not worse in the mornings and associated with severe stiffness. Pain may also increase after activities such as walking, stair climbing or kneeling. Pain and stiffness is also at its worst after a period of inactivity. The pain may often cause a feeling of weakness in the knee, resulting in a locking or buckling as a result of this disease. Many patients report that changes in the weather also affect the degree of pain from arthritis.