What happens if you bend after a scoliosis surgery?

Answer 1

As long as your movement isn't restricted anymore (after surgery, you'll have various post-operation restrictions that your surgeon gives you), nothing. Your spine will be solid bone where it was fused, so if you try to bend it, it's just like trying to bend your thigh in half - impossible. The muscles required to bend your spine are still there, though, so if you try to bend your vertebrae the muscles will strain to perform the impossible, and it sort of feels like trying to lift an insane amount of weight - impossible.

As long as you're not fused all the way to your tailbone, this shouldn't affect you too much. You can still bend over at the hips or kneel down to pick things up off the floor. You'll have great posture all the time. Most people don't have any problems living with fused spines; I was a varsity captain in tennis and had a fused spine all four seasons (fused T3-L3).