When I was about 7 or so my mom sewed her finger into something she was working on. It was one of her right hand fingers and she couldn't get her finger off the needle while it was still on the machine. I had to unscrew the needle clamp screw and then once the needle was out of the machine she use a pair of pliers to pull it out.
I was a bit traumatized by that. Needless to say I do keep my digits away from the needle.
Joe