First of all, it may be scar tissue from the surgery. It may be the surgery didn't work or the surgeon messed up. It may be the discs weren't the problem, as they often aren't. I would say you need to visit your surgeon, and if you don't get good service see another for a second opinion.
sounds painful. Okay, I had similar issues long ago. They would release my hamstring muscles and quads and it helped with my lower back. It's all interrelated. Does stretching help? I've also gotten rid of sciatica with careful stretching of that same area.