I know there have been posts/threads about this, but what has been your experience with bilateral symptoms?

I know someone who said that sometimes she feels like she doesn't have any knees. I said, "You mean, you feel as though your knees will give out on you?" And she said, "No, it's kind of a numbness, or tingly thing...like I can't FEEL them...that they aren't THERE."

I have had MS symptoms on both sides of my body, but not simultaneously in the same body part. Interested in your input.