This is a true story. It really happened to me.

I was at my Ob/Gyn's office for a procedure. I was lying on the table (you can imagine the position) when my doctor entered the room. He pulled up the stool to position himself for the procedure. When he sat down a wheel fell off the stool and he tipped over.

His comment was, 'It looks like this one has been used a few times!'

Good thing his patient had a good sense of humor.