Well good question! It was very intense lower back pain. Xray showed mild spinal degenration...I am 51. Being that I went from deadlifting 405 to being almost unable to get out of bed over night made me very suspicious of arthritis...which is effectively what the Xray showed.

But there was no acute injury. I wasn't maxing out or anything and I have injured my back years ago deadlifitng so I know ehat that is like. Nothing at all like that this time, but the pain was so bad I couldn't even do standing curls. Getting out of bed was hard every morning. Still is to a degree but nothing like a few months back.

So several months later my back has 'healed' a lot and I'm back in the gym. Still not loading the back so no deads or squats for now. Deads are one of my favorites but at least for now they are on pause.

Still not sure what happened to be honest, but really glad to be back in the gym again.