A knee prosthesis is a medical device designed to replace a damaged or diseased knee joint. It is commonly used for patients suffering from conditions like arthritis or after severe injuries. The prosthesis typically consists of metal and plastic components that mimic the natural movement of the knee, allowing for improved mobility and pain relief. The procedure to implant a knee prosthesis is known as knee arthroplasty. During this surgery, the damaged parts of the knee are removed and replaced with the prosthetic components. Rehabilitation and physical therapy are essential after the surgery to help patients regain strength and function in their knee.