Begin by making a spurious distinction. Befuddle the reader with your analytic wizardry. The reader will enter a logical trance, from which she will be unable to recall the initial spurious distinction and will feel strangely compelled to accept your conclusions.
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.