Check out my profile picture of my left shoulder and tell me if you see anything.
Hi there!
The acromion is a part of the scapula bone (shoulder blade) and is located towards the back side of the shoulder joint. Pin arising from the region could occur due to injuries to the bone/ tendons/ ligaments etc or due to other causes such as neuro-muscular issues, inflammations etc. I would suggest discussing the situation and the management plan in detail with your treating orthopedician.
Hope this is helpful.
Take care!