An X-ray, of course, would find out immediately, if I could afford health care.

So my grandmother, who is just recovering from three weeks of hand-on-the-phone-ready-to-call-an-ambulance bronchitis, says she knocked her glasses off the nightstand and under her bed, would I please get them?

So I went into her bedroom, got down on the floor, and scooted over to where I could get under the bed to look. In the process my left knee lightly tapped one of the legs of the bedframe.

Cue a couple minutes of crippling, blinding pain and loud uncontrollable cursing.

When I recovered enough to get back on the floor to look, of COURSE the glasses weren't there, or anywhere around the nightstand for that matter. I made several trips back and forth to the den to try to get my grandmother to be more specific about where she last saw them, and each trip required limping because my knee was STILL in intense agony.

Two hours later, the pain is gone, and I still don't know why the hell it hurt so bad. I didn't get a running start, do a home plate slide and bury the metal bedpost into my kneecap. It was just a light bump. If I'd hit my head that lightly, I probably wouldn't even make a sound. But that light tap, right in the middle of the kneecap, had me thinking happy thoughts of amputation at the hip socket.

This isn't the first time, mind you- similar light bumps to my shin, and also to certain toes, have the same effect- pain out of proportion to the force and trauma involved.

But I don't know why, and I can't afford the answer.