hello people.. just to add to the gang i know of someone who had the same problem, Wikipedia reference-linkMRI revealed no abnormalities... so he(also a physio) did a few stretches (sural nerve) and the pain actually had come down.. one easy tip could be to do a slump test and find out if there is any neural restrictions or any fascial tightness along the deep or superficial fascial line and then treat accordingly... hope this helps