Question
I had surgery to correct scoliosis (Harrington Rod from L4 to T?) 28 years ago. In May 2009 I had a disk replacement at L5-S1 to repair a herniated disk.  I have far more sciatica (burning sensation down back of right leg right to the toe) than expected since the surgery.  PT was started in August 2009 and seemed to help some but the pain never really went away.  Sciatica started getting worse in late October (mild sciatica & muscle weakness in left leg rather than the right leg where it had been since before the surgery).  
About 10 days ago, all the pain switched to the right leg; the sciatica is so severe that I can't walk, sit, stand, lie down or anything for more than a few minutes without the burning sensation increasing.  It feels like my hip is "stuck" in the wrong position.  I am on Gabapentin (since the surgery) for the sciatica but it doesn't take it away completely.  My surgeon is saying he needs to fuse L4-L5 and L5-S1.  My chiropractor says that surgery would be useless as it is in the SI and NOT in L4-L5 or L5-S1.  
Today, I had a "drop-table) adjustment and it felt great for a while but I can feel the sciatica coming back.

Is this SIJD?  Would I be a good candidate for prolotherapy?  Are there special stretches/exercises that I should be doing?  Should I have more spinal fusions? Thank you so much for offering your time to answer our questions.

Answer
Its hard to give an opinion on this situation without any mri or xray results.
The harrington rod surgery is very painful and cumbersome, and can contribute to your current condition. surgery does not guarantee you will be out of pain . In fact, surgery research shows you will have a 3 out 5 chance to have more if not equal the amount of pain 5 years later.
i think that if the one adjustment helped you, you should continue with it as he recommends. you may also want to try cold laser therapy. It weill take time but im sure your chiropractor can help with some of the symptoms your having.
good luck! your current doc should have some stretches put together for you.