I have had 7 knee surgeries and my knees have many, many screws holding them together. I use my knees as a safety example at the beginning of each year, including showing them x-rays of my knees. I got the giggles the other day when a sweet little kindergarten girl came up to me after class, handed me a screw she had found on the gym floor, and asked, "Mrs. Winn-er, did your knee lose a screw?" I’m glad she clarified "knee".