Cutting my hard cast off

I didn't like the feeling of her cutting my cast off. She told me that it couldn't cut me, but when I had a cast cut off of my arm a few years ago they did cut me. She told me that the thing they use now just vibrates instead of turning and there was no way for it to cut my skin. I didn't like the vibrations it made and when she got close to my incisions I could feel it and it wasn't a good feeling. I did live through it though. He had a lot of padding in there as you can see in the picture where she is cutting the gauze.
You can see in the picture where she is cutting the cast off that I was holding my leg trying to keep it from vibrating so much. I was pretty tense and trying hard NOT to pull my leg away from her.