I asked Jim, who was 95 at the time, how his arm got buggered up. I had known him for a couple years, and had installed a big off grid solar system at his 450 acre home. This guy was a WW2 Marine Air Corp pilot, with 2,000 hours of combat time, flying Corsairs off of carriers. After that he went on to a 50 year career as a crop duster. Then he retired to a Nevada ranch and flew his Super Cub all over, without using an airport. None of that "got" him. I had noticed he partial use of his arm but didn't realize it had been tore off and flung 30' away, then packed in ice and sewn back on! His nurse daughter told me this, all he would say about it when asked how his arm got buggered up, was " PTO".
I have a bad habit of getting off the tractor while the rear blower is engaged, and hand cranking the chute to a different direction. I never come closer then 24" to that spinning drive shaft, and don't have loose clothing dangling, but still, every time I think of Jim's single word comment.