Good to hear from you and wow what a year for you! I am glad your surgery was successful and that you are back at it, no small accomplishment.
The pain is most likely pressure, impingement, or entrapment of an intercostal nerve along the side of your sternum from the wires. It may not be that but your symptoms and the ability to localize it to a specific point suggests it. If that is it, then the fix would probably be removal of the wire at some point. Best discussed with your doc as is ultimately above my pay grade as they say!
Hope this helps you find some relief and I hope you have a blessed, healthy, and prosperous 2018,