Hi- There are not any doctors here...
Tramadol won't work because you already take Sub which covers your receptors and disallows any opiate from penetrating. Although Tramadol is not a true opiate, it is "opiate like" in this case.
Tramadol works on the same receptors that the subs attach to, hence the tramadol won't work as vicki said. You most likely won't go into w/d. Have you tried any herbal pain remedies such as cinnamon or turmeric. Both of these help to reduce inflammation which causes pain. I was on massive dosage of oxy to control my pain but since I got clean I have searched for alternative ways to control my pain and have found that there herbs really helped. Take a look at the article below it explains the hows & whys:
http://www.livestrong.com/article/362017-arthritis-pain-relievers-with-turmeric/
I hope you feel better---Rick