Pain in back of left thigh. Severe when coughing, reclining or laying in bed then getting up. Can t walk for a few minutes intense pain, equivalent to labor pains, worse if tilt pelvis forward, or try to lift my butt up from bed to switch positions, cry oit in pain often brining me to tears. Subsides after 10 minutes of getting up, unable to walk when it is going on. Same pain is felt when bearing down. This had been constant for 1year now. Negative results from doppler ultra sound. No pain in my back, or buttocks. Stabbing, gripping nerve pain. Only in thr back middle of left thigh. Suggestions please. I am really flexable so no problems there.