I had a microdiskectomy on T6/7 in 1996. Two-inch incision mid-back. It fixed the problem - the herniation - but not ALL of the pain. It was much better, but not completely gone. Ever since the surgery, though, my skin is almost numb to the left of the incision around the left side of my back

I think it may be due to the way they positioned me, but I'm not sure. Maybe there was some nerve injury.
Now it is herniated again, along with T7/8, T9/10 and one other one, due to two car accidents in 2002. My neurosurgeon told me he thought my mid-back pain was coming from my neck, and did an ACDF on C5/6 almost a month ago. I'm hoping he was right, but I am still having some of that pain which discourages me. If it continues, I might just ask if there's some way to kill the nerves back there!
Good luck to you - let us know what the doctor says/recommends. I have also heard that thoracic disc herniations are rare, but that obviously doesn't do US much good, does it?