Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Knee Replacement ?
    ### Response:
    Knee replacement is surgery for people with severe knee damage. Knee replacement can relieve pain and allow you to be more active. Your doctor may recommend it if you have knee pain and medicine and other treatments are not helping you anymore.    When you have a total knee replacement, the surgeon removes damaged cartilage and bone from the surface of your knee joint and replaces them with a man-made surface of metal and plastic.
    