worst injury?

[drache]

I may be slow, but where do you keep your brain, James?
I just can't think of any appropriate three letter words you wouldn't be able to write out . . .
can you give me a hint?

btw
as a child I was once hung on a tree by a horse
no serious injury - just a tree branch puncture wound on my backside - but pretty funny judging from witness accounts

[Stefan-A]

I may be slow, but where do you keep your brain, James?
I just can't think of any appropriate three letter words you wouldn't be able to write out . . .
can you give me a hint?

The secret word is "***".

I'll give you a hint after all: Equus asinus.