When you move your arm, the rotator cuff tendon might rub against the bone. Removing the acromion, which is the piece of bone it is rubbing against, can give more space for the rotator cuff tendon to move and can reduce pain.
An acromioplasty may be done arthroscopically, using minimally invasive techniques, or in a more traditional open surgery. Your surgeon will let you know which method is right for your shoulder.
After surgery you may need to wear a sling. You will go to physical therapy and do rehabilitation exercises to continue improving your shoulder after the surgery.