For anyone who is having back trouble with a conventional office chair, transition to an exercise ball if you can and then a standing desk.
will not be sitting on an exercise ball though, seems weird to me.
I also once owned a gymnastic ball to sit on at work. As a sort of preventive measure for the sake of my back.
I felt it was kindof weird weird, but I thought it was the rationally correct thing to do (one year earlier I had started wearing a bycicle helmet and that still induces the vague and irrational feeling of being an idiot to this day).
The only actual problem I found with that ball was that apparently the ball hadn’t been designed to be constantly pressed onto a hard floor with a force of more than 800 newton.
So one day it desintegrated right under my ass. Imagine my colleagues’ merriment.
So, from my personal experience: if you are happy when your dear colleagues are, and you are ready to buy a new exercise ball from time to time, they are great.
By the way, for my self, I decided that my back would have to look after itself for the time being.