I think I am at the "O" in old, not the "O" in young, now. I was inventory-ing books and pulled a box down from overhead, over-balanced and heard this ginormouse pop in my shoulder. Three days later, I can't brush my hair. I can't flip the sunvisor in the car. And hauling my little cart around at work is torture. So I filed a worker's comp report and trotted off to the doctor. Three hours and an x-ray later, I discovered that I don't have arthritis but since an x-ray doesn't show tendon damage, the doctor really couldn't tell if the rotator cuff was truely torn, or not.
Hurts like heck, though.