Lipoma Causing Back Pain?

I have two lipomas on my lower left back that the doctor thinks is causing my lower back pain. The MRI showed my spine to be in good condition, so he feels the dull ache I've been having (being forced to sleep with a pillow under my left hip when I lie on my back at night) is due to the lipomas. It makes sense in one respect, but I hate to go through the surgery only to have the back ache continue. Any thoughts would be appreciated!