Sorry to hear about your back.
If your doc would approve it, you might try Sam-E, sold at Sam’s Club. It’s for joint flexibility and also is a liver cleanser and a mood improver (I first put mood elevator but that looked odd to me).
I only take a half dose, 1 pill each morning on an empty stomach, and I like it better than glucosamine. The reason I don’t take a full dose is that I don’t like having to run to the ladies’ room constantly for potty breaks.
Thanks for the tip!