Ah. Mine was to set while waiting for surgery so things didn’t tighten up and be harder in the OR. I had tibia and fibula snapped and dislocated ankle. They got the joint back in place and straightened the leg, then put it in a splint to wait in.
They practiced the movements while I was with it and it seemed very violent and physical. Then they dosed me to do the real thing and the next thing I remember was sitting there wondering wtf just happened.