I was running 3 months ago and developed a sudden pain in the vicinity of my left ischiopubic ramus. Since then I have that same pain in that area each time I run. I have now developed extreme pain in my left buttocks after sitting for 5 min or more. I have a negative MRI. PT with e-stim has not helped. I can walk, swim or do the elipyptical with no pain. My orthopedic has no answers. I ran 3 half marathons in 2010, pain free. This particular run was an easy 5 miler, 2 weeks after the last half marathon. I can not run now as it is too painful.