Lots of pain. Have had three cortisone shots over three years.First one was good for 12 months. Next one 7 months. Third one was a dud! In the meantime an xray has shown that the shoulder joint itself is in very bad shape ie all soft tissue gone from socket area etc etc.Now I am told that the shoulder pain is from bone spurs in the socket?and the shoulder pain is just referred pain. I am confused! Where should I have this proposed shot? Shoulder or tendon area? Should I get an MRI first?Help please!