I still do a lot of research on back pain/ surgery and bodybuilding. I've read a bit on Dave Draper but he has some excellent information on this topic. Have a look.
He also is reading Starting Strength - Basic Barbell Training as am I. I am still working on the first chapter which discusses The Squat in great detail. Amazing really, I was doing quite a bit wrong. I use to use the Smith for Squats and a Freeform machine both are problematic with squatting and your risk of injury is much higher. If you are even considering bodybuilding competitively or as a hobby this is a must read.