Thank you, I was trying to do the planks from my feet, not my knees. I'm almost too scared to even try the latter now, merely holding the plank pose for ten seconds has triggered a pretty nasty flareup that is still giving me problems.

Whereas you had a slipped disc, I had no nerve root impingement. So the neurologists are telling me that my DDD can't account for the neuralgic pain and parasthesia in my feet. STILL trying to get a diagnosis, STILL have no clue what is happening to my body...