I don’t know how exactly it happened but I put out my back! There I was at work, merrily trying to readjust a swivel chair by pulling on the lever and trying to pull the seat up at the same time, then wham, my back seizes up!
All this at the semi-young age of 32!
It hurts to sit down, it hurts to walk, and it hurts to go to the toilet.
A sore back is not fun.