Hi ~ You're right, a pinched nerve doesn't show up, but do you have any discs that are bulging or herniated?
Sciatica can be caused by more than just a pinched nerve. They can be caused by falls, tumors, spinal stenosis, spondylolisthesis (where one vertebra slips forward over another), trauma , piriformis syndrome (hard to diagnose), and several other things.
Believe it or not, I've had it for 27 years, and I'm so sick of it i could scream! There are days that it's so darn painful I can barely walk! My doc put me on a new med that was working great, but I still have flares, darn it. I thought we had it licked, but I guess not.
Doesn't your doctor have you on any pain medication? You might ask him to send you to physical therapy, as MANY times that will correct sciatica! So ask him for a referral. If that doesn't work, ask for a referral to pain management. They'll help you out. But first try physical therapy.
I wish you the very best. Please keep us posted, will you? We'd like to know how you come out! God bless and take care. Hugs, Lee