Hi mikeo and welcome to the forum!
We've seen a few members on the forum who also have AS. From what I've read it can be treated with Remicade, Humira, Sulfasalazine, Prednisone, and Methotrexate, which are all possible treatments for Crohn's as well. Are you on any medication for Crohn's right now?
Feel free to check out the forum's wiki on AS:
http://www.crohnsforum.com/wiki/Ankylosing-Spondylitis It mentions treatment and there are threads linked down towards the bottom that talk about AS. Here's some more reading on possible treatment:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001457/
Besides NSAIDs such as Advil, Aspirin, Motrin etc which are perfect for that pain but bad for Crohn's, there's other pain medication such as Tylenol, Tylenol 3, Tramadol, Norco, Vicodin etc. Controlling the pain through treatment (meds listed above in the first paragraph) rather than pain management may be best as you do run the risk of dependency with narcotics after long term use so its best to try and limit pain meds to as needed. Also these pain meds (besides Tylenol) can make it difficult to function normally and you may not be able to drive.
Edit: I took the liberty of editing your thread title in hopes of you getting some more responses.