re your specific condition...your doctor should directly consult with any Yoga teacher prescribing exercises.
Yoga is wonderful. There are certainly Yoga postures that will benefit just about any health condition...but every case is slightly different and, again, any Yoga postures for treatment should be cleared by your doctor.
There are Holistic MD's...they are full medical doctors with an orientation toward natural medicine, if you prefer one of those kinds of doctors.
I am not suggesting that natural healers are not qualified to treat conditions. However, Hatha Yoga teachers are primarily exercise instructors and not healers, per se. It is not likely to find a Hatha Yoga teacher with extensive experience in working with this condition. And unless, they have had, say...oh, 50 people with the condition and that kind of experience, they are simply not going to be experts in treating that condition.
But working with an MD or other expert with profound experience with the condition should help...
With back problems you also might want to look into better mattresses. Some people do well with those memory foam mattresses, like Tempur-Pedic (some of the cheaper brands really smell awful, so be careful).
Might want to look into movement therapy in a pool, as it is very low-impact...
and again, run everything by your doctor. Even if a therapy is generally good, doesn't mean it is specifically for you.
best of luck,