I'm having the same problem as you two guys! I wake up somewhere between 2 and 5 AM every. single. night. with huge mid back pain.
I'm very and very tired now, I can't have a normal sleep, I can't rest normally. Every night I end up taking some pain killers like ibuprofen or at least some other that I can find in pharmacies and then I go to sleep again and stay awaken for more than an hour sometimes. This horrible scenario has been going like that for a little more than a year and for this year I can't remember when I had a full night of sleep!
I've tried every. freakin. thing. that I could imagine to get rid of this and zero effects. Of course I've visited a doctor, of course he made a x ray and of course he found out - nothing. Made a mri test too and - nothing again. I've been to an expensive physical therapy for 2 different periods of time and again - nothing. I've been prescripted to take shots of muscle relaxers - nothing, I've taken vitamin supplements as you can understand - nothing. I have bought a new freakin expensive mattress which was supposed to help people who suffers from back pain at night, it helped me with - nothing.
I'm so upset and angry I can't express myself. I've spent a lot of money, a lot of time and literally nothing works on me. I can't understand why, I'm not having another health problem but this and I'm young. The pain sometime occurs during the day and I'm almost 100% sure that it's something muscular. I just can't believe that doctors can't find a cure for this. However I'm not stopping in searching what will help me, but it's getting much harder than I thought.