Back injury is not exclusive to pilots as they get older I had far more back problems in my 20s than ever in my 50s.
Before considering your case I would look at how active you are? Is your weight what it should be how much stress do you carry etc! Ie is the case the final straw that broke the camels back or the item that caused it to break?
Hope you dont take this the wrong way as it is supposed to be constructive.
Hope the op works out well
Pace