Frequently, when someone gets trapped like that, they are alive. Until the train is jacked away from the side of the platform.
They get twisted at the waist like a plastic bag. It pinches everything off, including the nerves that transmit the pain. Think they're fine. When they body untwists, everything falls into the pelvic cavity.
HBO used to have a show called "Taxicab Confessions". One of the episodes had a firefighter explaining this to the driver. A producer for "Homicide: Life on the Street" saw that and made an episode about it.
I remember seeing that episode, imagine having to be the guy who tells him he's going to die as soon as they move the train and there's nothing they can do.