Knee osteoarthritis is a disease that can affect the cartilage surfaces of the joints. In an arthritic knee, the cartilage is worn away, the joint surface becomes indented and eroded, and the joint becomes uneven resulting in pain, stiffness and instability. The most common type of knee arthritis is osteoarthritis. This degenerative form of the disease is most common in patients over the age of 50. It is often confined to the heavily weight-bearing joints of the lower extremities, including the hip and knee joints. Patients with osteoarthritis often develop bone spurs or bony growths around the joints, which can affect joint mobility. Rheumatoid arthritis: It is most common in younger patients, especially women. The disease often involves the surfaces of multiple joints, causing patients to complain of similar symptoms in their hands, feet, shoulders, hips and knees. Common symptoms of rheumatoid arthritis also include anemia, weight loss, and recurrent joint swelling with pain, stiffness, and joint instability. Traumatic arthritis: This is the result of severe trauma causing damage to the joint surfaces and may be accompanied by muscle, tendon and ligament damage resulting in extreme joint instability. In some cases of knee fractures, aseptic gangrene may develop even after the fracture has healed. Impaired blood supply to certain areas of the knee may be attributed to streptocytosis or a side effect of drug therapy, but no definitive cause is known. Infectious arthritis: This is often due to infection from other parts of the body that is broadcast through the bloodstream to the knee joint and takes up residence. The invading bacteria and the body’s own immune system can rapidly destroy joint cartilage over a period of days. Open trauma to the knee joint can also lead to the development of infectious arthritis. Most cases of this type can be cured with medication, physical therapy, and limiting the movement of the overstressed knee. Total knee arthroplasty: This involves removing the damaged part of your knee that needs repair and replacing it with an artificial component called a prosthesis. During the procedure, a set of implants specifically selected to fit your needs is placed into your own bone. The patient’s prosthesis is fixed with a type of acrylic cement called polymethylmethacrylate. This cement has been used successfully in dentistry for 45 years and is a very strong material that is compatible with the body and provides excellent fixation and healing within 15 minutes of mixing and purchasing. The bone cement is injected under pressure and the implant is placed in place. Due to the strong bonding of the bone cement, most patients are able to perform weight-bearing activities on the affected limb within a few days of surgery.