I have had both total shoulder replacements. I strongly recommend my surgeon, Dr. David Dines at Hospital for Special Surgery in New York. I also have had both hips. The shoulder is much easier. The key is NOT to spend weeks post surgery without movement in a sling, except as a precaution when around crowds. HSS has done research that demonstrates quicker recovery with small movements, following proper protocol, right after surgery. Total recovery and able to play golf in 3 months. Don't wait. It's very clear from the x-ray that the cartilage is gone, then the cortisone won't help much. Just get it done and get better.
