I first experienced proper back pain around 18 years ago - something ‘went' while playing tennis, encouraged by years spent sitting at an office desk. It has limited me ever since, and though things are ok on a day-to-day basis but every now and then it ‘goes’, with severe pain for a couple of days. Standing is very difficult, and more than once I’ve had to drag myself out of bed and along the floor to somehow clamber onto the loo. I suppose this is why I’ve remembered various quotes on the human spine.
A note to those who haven’t had back pain - to keep your discs in decent knick, stretch your spine regularly (toe-touching and arching both back and sidewards) and keep your core muscles active. Stand and walk as much as possible. If you do have back issues or are concerned they are coming, get yourself Sarah Key’s Back Sufferers' Bible - it explains all.