Why is clicking my knee joint so painful, and should I be doing any exercises to help?

Glucosamine helps to cushion the joints!
Not saying that this will work but.....I have "floating" kneecaps and my doctor recommended strengthening my quadricep muscles to help keep my kneecaps where they are supposed to be.  Always best to contact your doctor though, just in case you are looking at something more serious like osteoarthritis or even worse.  Good luck.

First you should find out why your knee is clicking. It has 5 possible causes. 4 of them are because of injuries and tears. The 5th cause is arthritis. Consult your doctor, he will might do an x-ray. A normal knee should not click...