I Have Been Diagnosed With Bone On Bone In My

I have been diagnosed with bone on bone in my left shoulder. I was advised of three options for the pain. Ibuprofen, cortisone injections or total shoulder replacement. Every morning I wake up with a very sore, stiff shoulder. I can't take the ibuprofen because it will affect my heart rate (my cardiologist and I already discussed this), I have tried Tylenol for arthritis, but it doesn't seem to help at all. I want to know how would the cortisone injection help with the discomfort.