Thank you Billin LA. (and thank you for your e-mail notice), good to hear it works. As we grow older, it's easily happened to neglect back bends because forward bends become easier than during the years of growth. Therefore IMO back bends (self paced) are a way to slow down ageing of the spine.
Greg, there are several details that often get wrong in Ardha Matsyendrasana. If you've a mirror, check that none of the shoulders gets higher than the other one, and that the spine is lengthened and straight (and especially, that the heart region is not pulled in/backward). Don't rush the bind (you can use just the tips of your longest fingers, or hold a sock with your palms instead). IMO, Nakrakriya (the crocodile twist, lying on your back) is safer/gentler because you can do it dynamically from side to side, in pace with (very slow, deep) breath. If you've lower-spine issues, you can even use the lungs as an "airbag" in Nakrakriya: Inhale - twist under kumbhaka - get back to middle, exhale - inhale twist to the other side etc. (i.e. the standard breathing scheme reversed), and there are also dozens of leg variations to try (to see if any of those makes the spine get better).
Heal fast & safely
HaTha
