Well, I don't think so. I hadn't adjusted anything and it looks like the saddle is where it always is. I attribute this (at least in part) to a bad habit of very poor posture at the computer over the last year or so. I sometimes sit and turn my chair sideways, and then put my left leg up on a stool, and slouch down in the chair I'm in. Not exactly good posture. I think over time it's put a strain on my knee.

And even if that's NOT the cause, this is a good wake up call to knock off the poor posture at the computer.