98% of my back pain is gone since we bought a tempurpedic mattress!!!!!!!!! and hubby too! the other 2% is usually self inflicted from heavy lifting 

  I woke up every morning with a back ache.

 (and about three times during the nite) 
dont know if this could be part of the problem for you or not but dont dismiss it like I did. Our mattress was not a no name or cheapo, or too old. brand name and only a few years old...so I could never believe that was the real problem!!!!