For a couple of weeks now, my right knee has been giving me fits. I assumed it was arthritis at first, but then the pain increased gradually and reminded me of the time I hyperextended one of my knees several years ago. Been hobbling around for a few days, using a cane when walking farther than from room to room. I figured I hurt it when I hopped off the lawn tractor week before last and landed with some unsteadiness. This past Saturday, I broke the belt on the tractor and had to end up mowing the back yard with a push mower before it rained, planning to go the…