This man is a 77 years old male with long standing left shoulder pain and weakness. His initial x-rays confirm the presence of a massive unfixable rotator cuff tear. We know this because the position of the humeral head is immediately beneath the acromion. He has developed pain and weakness as a result of his untreated tendon tear.

The labeled space below indicates how little space exists between the two bone surfaces. There is no room for the rotator cuff tendons in this limited space.

Below the same patient has undergone a reverse shoulder replacement. He now has complete pain relief and is able to lift his arm above his head to 130 degrees at only 2 months after surgery.