hi shane....
I have the same pain often. no other simptoms, but such pain is the one that comes the most often. lower back is sort-of daily hurt, but the leg is a measure for me how am i doing - any bigger change of weather makes me "print" when i walk (my footsteps look a little bit different after my walk in days when it hurts, i call it "printing" cuz you can tell my trail because one step is shorter and less secure than the other)...
my pain is due to the pinched nerve (ischias) in the lumbal part of the spine and my pain usually goes away a little bit after some walking, like, an hour, or something, once my leg gets warmed up, but if it was really bad to start with - it doesn't go away, it chases me like on marry-go-around. when it was really bad, my knee would fail to support me randomly - it would just skip a step, like i didn't ask it do do the step for me, it'd bend in the middle of my walk.... i never fell down,but i had to be really careful because i could and would kneel at the funniest and oddest moments...
however, in those days, i find practice particularly hard to do, yet enormously useful. if i start practice patiently, slowly, with slow and shallow moves and gradually adjust it, it takes time and some pain to do it, but it can really really help me through the day. of course, sometimes it hurts too much for practice, but again, luckily for me, not so often, yet.... chiropractic would also help me sometimes, but i've read somewhere here that chiropractic is not recommended for people with AS, so please take ALL MY ADVICE as something that needs to be run by someone more experienced and knowledgeable... i am a newbee (just got diagnosed recently), although that my methods of practicing and seeing chiropractic occasionaly help me, it might hurt someone else at different stage of AS, or with different disks fused, etc. also, i've had one of the best chiro's in the country available around here (i was his best man at the wedding. now he is living around vancouver, CA.. if anyone needs a home visit, i am be happy to recommend him...)
also, such ischiatic pains are what made me go to the doc in the first place, after years and years of enduring my pain. in fact, i am still coping with pain well enough taht i didn't pick up painkillers she prescribed to me (knock-knock on the wood). i have plenty of time to start with those, i don't want to until it gets so bad that i won't be able to endure it no more without a glossy colored happy pills...
all the best,
L.