My left knee makes a terrible, ratcheting sound when climbing steps. I don't notice it during walking, and it doesn't cause me pain, but I can hardly stand the sound of it when I go up steps. I just wondered if it is a sign of arthritis, or if I should get it checked out. My mother seems to think it is just a sign of aging, but I don't want to cause any damage that may take me out of commission. Any similar experiences or advice?