My wife came home Thursday afternoon after her knee replacement surgery. One of the things they provided for her was an ice box. This consist of a plastic, double lined, box that has a built in pump. There are two hoses that lead to a bladder that is strapped to her knee. You fill the box with ice and water hook up the hoses and turn it on. It circulates cold water though the bladder and back to the box to be cooled again. It is a big help in keeping the inflammation down. So ever since she has been home I've been collecting plastic bottles to fill with water and put in the freezer to keep this thing going. I have enough of them now to keep the machine pumping cold water around the clock. So far she hasn't touched any of the pain meds they gave her. She says having her knee kept cool has helped her a lot with the pain.