I have this too. It hurt to touch the chest and was quite a sharp pain. It came on after my back surgery. I suspect from laying around so much. Doctor told me to take an antiinflammatory for it. I think I took Aleve. that helped immediately. Then I started pool walking and doing some arm exercises in the pool and that helped reduce my pain all over, including the chest. I think muscles get tight. I noticed though my back problem is in the lower back, my whole back was tight until I got into the pool.