15 years ago they removed a disc L4-l5 as it had degenerative tissue amd bertebrades were fused with no plates, bars or screws.. Currently had a serious injury and the cramps on my left leg and lower back surgery area are just killing me, i guess i torned something in there. I have been told that to avoid this a vertebral separator fan be inserted in ther. The catch is that they fuse my vertebrades 15 yesrs ago. Has anyone had thiis done.?