The best part of watching the Feud is seeing one of these brain farts happen. They are cringe inducing at times, but the other family members will still clap, say "Good Answer" and look expectantly at the board.
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.