Not an injury but in terms of pain I have occasional severe cramp in my calf muscle.
I generally get a few seconds warning where the pain is slowly building up, at it's peak the pain is terrible best way I can think of describing the feeling is like a poker being jammed into the muscle from the inside my leg, with the muscle feeling like it's trying to burst it's way out of my leg, the pain subsides after a short time leaving me with an aching leg for anything up to a week. I've only ever met one person who's experienced cramp to quite the same degree, she's had 3 kids and described it as the worst pain she's experience, much worse than labour pain, though of course it is over a lot quicker.
