I read through all the posts here, but they do not get to the root of the issue, which I would be willing to bet is in your hips. When I hear someone has back pain, sciatica and tight hamstrings, it almost always means they have some form of kyphosis. Simply put, that means you have a flat lower back. that flat lower back is causing the vertebrae in your lower back to compress and put pressure on the delicate nerves back there which causes pain down the leg. Until you deal with the postural distortion in the hips that is causing the flat low back, you aren't going to get much benefit and start feeling less pain.

Check out your posture in a mirror. Take off your shirt and look at yourself from the side. Do you see your butt tucking under your pelvis? Do you see a pretty flat lower back? If so, that would really help explain all of your symptoms. You will need a good rehab program to help correct the kyphotic posture, which, by the way is extremely common. Some of the major components of it are- tight hamstrings and glutes, weak quads and core, including psoas.

talk to your therapist about it and see if they can design a good rehab program for you. Otherwise, if you are looking for a cheaper alternative you can follow at home, check out the SMS low back program. I have seen that program really help a lot of people recover from low back pain without drugs or surgery.