Hi Physio and thanks for the reply, I'm 36 by the way - will update profile when i figure out how to!. I have tried a different physio and she says the areas of tenderness are the raised areas of the SI joints (i think these are known as venus dimples?).

She thinks that the pain i feel here is from nerves at the L1/2 disc. To be honest it doesn't feel like sharp nerve pain to me, more like a nagging, throbbing pain which is made worse by pressing on the 'raised' areas themselves. She checked the movement of my legs and there is no restriction in movement to suggest a SI joint problem.

The only thing the Wikipedia reference-linkMRI report mentioned was a 'little low signal change on the iliac side of each joint superiorly representing sclerosis'. I know sclerosis means hardening of tissue- could this be significant. I am getting desperate to find out what is wrong with me as it has gone on for a couple of years now!

chris