I am experiencing sharp pain in my sternum and some area of my chest whenever I change my position whether I'm sitting or while lying down. I first experienced this problem 3 years ago. Lt was not as persistent as it is now. There is a sharp pain in my chest area for few seconds. I've to pop/crack my chest joint in order to get relief from the pain. I can live with this pain but it's not ideal if a person has to deal with this everyday. I've visited a doctor regarding this. He told my that it was becoz of low level of Calcium/Vitamin D. And advice me to take Milk and few calcium medicines. I really don't think that there's a connection between this. Please help me if you can? Case history: I am suffering from Scheuermann's disease. If it helps.