Severe nerve impingement, any hope?

Q: Hi, i'm a 29 year old female in pretty good shape. I fell over at work in Feb 2010 and had slight pain in back of left leg down to calf, that was gradually getting worse. Then, 5 weeks ago I woke up one morning & it was suddenly so bad that my little toe & left side of foot were numb and i am unable to walk without terrible pain. I am in pain constantly & taking endone, oxycontin, Valium & tramadol (just finished a 12 day course of oral steroids - predisolone, didn't seem to help that much). My MRI shows the following: L4/5: Intervertebral disc desiccation. A circumferential posterior annular fissure/tear is associated with a small broad-based posterior disc protrusion. This combines with mild facet joint/flaval hypertrophy to narrow the subarticular lateral recesses, with mild impingement of the traversing left L5 nerve root, while the traversing right L5 nerve root is contacted. L5/S1: Intervertebral disc desiccation. A large left posterolateral (right paracentral to left subarticular) disc protrusion projects up to 7 mm into the spinal canal and left lateral subarticular recess, with severe impingement of the traversing left S1 nerve root, while while the traversing right S1 nerve root is effaced. I would really like your advice. I have seen Osteopaths, Physiotherapists & accupuncture with no improvement. Can this be healed without surgery? I am very afraid that I am causing permanent damage to my nerve - Is there any chance of long term nerve damage due to this severe impingement? I I have also been told that I am an unusual case as walking is excruciatingly difficult for me however I can lie flat on my back & this is the position that is least painful. I can hardly leave my bed now, it just seems to be getting worse & worse.  Any information would be gratefully accepted as I am becoming more than desperate. Thank you so much, Mallika