My issue was at 2 levels, had the lower back pain, pain extending down the hamstring, calf and numb foot....couldn't lay on my back for 6 months as it was just too painful.
We talked about disc replacement, the Dr I went to has done them.....they are FDA approved in the US, just not often covered by insurance, but if that is the best option a Dr can often get it approved (according to my ins co.).
The problem with fusion on multiple levels is the loss of some flexability and the % of success is not that great. The thing about disc replacement that turned me off was the lack of statistics of success and the fact that there is a HUGE % of impotency because they have to sever a large number of tiny nerves to gain access to the lower back (they come in from the front and lay your guts out) and these tiny nerves are aften damaged and then your pecker doesn't work.
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.....maybe over time they will get this perfected.
I went for a discectomy where they removed the bulging portion of the disc and also removed as much bone as possible to make more room for the nerve root to move away from the disc.....so far I am about 90-95% pain free....just need to be careful not to do any stupid lifting.
Spinal decompression has worked miracles for alot of people also......send a PM to Anthony Oberti on here, he does spinal decompression and can offer some good insight. Good luck, I know it sucks!!