Does anybody know what's the exact problem? Is it muscle related or....?
Sounds like it was muscle related today ie in spasm but he's keeping quiet as to what the original problem was which, in my view, is his prerogative.
I know Andy used to do pilates so I hope he still does because it's really good for the back and keeping the core muscles strong. Apparently Ivan used to travel with a chiropracter. I see a McTimoney Chiropracter for my back and it has helped alot.