I had rotator cuff surgery and it is very painful. Expect pain for at least 8 weeks. It is tuff and going to physical therapy after helps a lot. Before surgery I was given shots and they worked like a miracle. But, they wear off. I just keep getting shots until surgery was scheduled. They don't like giving to many shots. No side effects of injections for me. Hope this helps. God bless you.
snicker5555
Most of the answers to your questions will depend on the specifics of your injury; torn rotator cuff injuries can range from small tears that can yield complete recovery, to large tears that cause chronic disability. Steroid injections will not heal a torn rotator cuff, but they reduce inflammation and pain, although the pain can get worse for a day or two after the injection before eventually improving.
It sounds as if your doc is trying to manage things conservatively; to reduce your symptoms and see if your body will heal itself. If the inflammation and fluid goes down you might get some improvement in mobility, but torn muscles generally take a long time to heal-- at least a few months-- so try to be patient.