Hi Lunabelle! Glad to hear your surgery is behind you - I hope that you have a textbook recovery (although they never tell you about the "cabin fever"!).
In answer to your question, I developed spinal scoliosis when I was 17. Despite conservative treatment I started losing feeling in my legs. I had to have extensive fusion, otherwise I would have faced eventual paralysis.
Like Texasgal, I had my surgery in the 1980's. I have had a lot of pain-free riding years since then. I do ache a little these days, but that is muscle-based rather than a spinal issue. I recommend yoga or pilates, once your Dr gives you the all clear, to help maintain core strength.
Wishing you all the best for the future.