Everyday I Experience Throbbing Pain Around My Lower Back. It

Everyday I experience throbbing pain around my lower back. It radiates to my legs and arms making muscular movement difficult and painful. I've been seen by the ER docs 5 times, family, PA, neurologist, and rheumatologist. My blood work shows high c reactive protein levels and slight anemia. No one can find anything, everyone is stumped. Where do I turn next? Any diseases I should look at?