Biker loses leg, doesn't notice.

Couldn't decide where exactly to put this, and though it's not conspiracy related it certainly is a medical issue! Mods feel free to move this if there's a better place for it.

I just don't understand how he didn't notice he had just cut his leg off! You would think that the pain alone would've been a big clue that something was very wrong.

Japanese biker fails to notice missing leg
TOKYO (Reuters) - A Japanese biker failed to notice his leg had been severed below the knee when he hit a safety barrier, and rode on for 2 km (1.2 miles), leaving a friend to pick up the missing limb.

Alot of the time when you are hurt so very badly your brain doesnt realize what just happened. Comes down to the nerves. The nerves where completely severed and didnt register the loss of a leg.

Have you ever cut yourself and didnt feel it until you look at the cut?

Many times in the kitchen I have cut myself and didnt know it till blood was running down my arm and noticed I cut my finger so deep that I didnt feel a thing till I looked down at it.. Then the pain kicked in and I was like I need to go to the hospital..

So yeah basiclly you just feel a jerk, or a tug on the part that gets ripped off.. YOu dont even know it happened till you look down.
Its our brains way of protecting ourselfs from extream panic..