How To Treat The Back Pain That Spreads To The Foot?

I had back surgery on March 2013 to remove the part of the disc that was ruptured. I woke up from surgery and all my leg pain was gone. I had a second back surgery in November 2013, to remove the ruptured part of the same disc again. I did leak spinal fluid with surgery number 2. When I woke up from surgery number 2 all leg pain was gone. I ruptured the same disc for the 3rd time in mid February. I just had spinal fusion on that disc last Friday. So I am 1 week post op. It s the last disc. The surgeon said the sciatic nerve was compressed all 3 times I ruptured the same disc. This time I woke up and the leg pain is as intense as it was before I had the 3rd surgery (the fusion). When I walk the pain is so bad I cry with every step. They have me taking 2 percocet every 4 hours, valium 3 times a day, and 2 antibiotics a day. All this medicine and I am still in severe pain. I have lost 30 lbs in the last 30 days because of the pain. I still do not have a appetite because of the pain. When I went into hospital last Friday I was dehydrated, but they started giving me fluids and did fusion anyway. I do not have the numbness or needle feelings in my calf or foot any longer. I just have severe pain from my left buttock all the way to the middle of my left foot. I do have ice packs that I put behind my back (I have no back pain at all). I will put ice packs behind my calf,behind my knee and on my ankle to try and help with some of the pain. What do you think is going on? And any idea when this pain might go away??