question: Hello Doc.  My mother has degenerative disc disease which has caused me to look more into my own symptons.  My lower back is sore many nights, usually needing a rub to soon the sharp pain....when I walk or move or sit - i feel as if my lower back is popping or the discs are rubbing - it sounds and feels like when you pop you knuckles.  It does not come with severe pain but the sound is concerning and I am now more concerned with my mothers recent update on her health.