Digital rectal-exam is the medical term for "having someone stick their finger up your ass."  So what's the deal?  Most men go through life committed to the fact their assholes are "exit only."  Having a finger pushed up your anus is suddenly like the portal to the New World and is a morbidly unpleasant feeling that ranks up there with getting festering hairs on your taint.  The only other option to this perceived humiliation is to slip on the old pinky cheater and slip yourself the finger and get the job done preferably in the closet, next, give yourself a breast exam.  If all feels well, you're home free.