And just for completeness sace, as nearly all answers here seem to address to the question "How can I avoid explicit torture scenes as a DM?"
So after going through the metagame topic of "Is it OK?" (preferrably in advance), and if it is OK, you can role-play it in a nasty simulationist fashion.
Prepare for the session as usual:
- research the topic
- print out some torture devices (in black and white) and maybe some mutilated human bodies
- play out the two concurrent processes of torture - the dialogue with the NPC, and enduring the actions of the NPC (torturer)
- don't start out by "I'll ask nicely", start with some pain in order to put the subject in a stressed state, where lying would be detectable
- tortured subjects usually get executed afterwords, if they hold no more information of interrest
but on the other hand, it's hard to force a player to give up info if he doesn't want to.
- Just hold still while I am doing to you eye what just happened to your finger.
This situation is intended to scare both the character and the player. The character ... well, this is clear. The player, because he/she knows that you, as a GM, stand up to what you declare, and his character is going to have that -5 on any ranged check ... forever (in a non-magic setting).
"Hold Still, I don't have good depth perception!"