I'm assuming telekinesis, but it's just a pet theory.
I do love this repeated BS about the arm-rests being too low for his height, as if that was some kind of culpable negligence. Personally I think he suffered the back injury through falling off a step ladder while trying to reach the top shelf of the Insurance Scams section in the Flywheel Shyster and Flywheel Memorial Library (but again, that's pure speculation on my part)
PDR