Re: Second discectomy
Jennifer--I can't be informative about all you ask, but the reason the lowest disks (5/1 and 4/5) get in the most trouble is because they are at the base of the spine, and thus have the most weight on them, supporting all the others. Still, there are exceptions, including me whose biggest problem is at L 2/3.
Regarding second surgeries, I believe there is more concern about scar tissue complicating the outcome, but this is an excellent question for your surgeon, needless ot say.
All the best with it,