It sounds like you have an injury to the acromioclavicular (AC) joint. Sometimes this is referred to as a shoulder separation. Treatment for AC joint injuries is usually based on the severity of the damage done to bone, ligaments, capsule, and nearby muscles. AC joint injuries are broken down into six categories classified as I through VI (from mild sprain to severe dislocation). The joint can be unstable in one of three directions: front and back (anterior-posterior), side-to-side, and vertical (up and down).
A type I injury means there’s no visible injury. The patient may have some swelling and tenderness right over the AC joint (front of the shoulder), but X-rays and motion are normal. A type II injury results in pain over the AC joint and positive findings on an X-ray (widening of the AC joint space). Sometimes there’s vertical instability but not often. Types I and II AC joint injuries are treated conservatively (without surgery).
Vertical (up and down) movement of the clavicle is more common with type III injuries. X-rays show the joint is dislocated. The acromion is separated from and slightly above the clavicle. Pushing up on the elbow puts the joint back together. But it may not stay there, which is a sign of instability.
It’s likely that you have a Type III AC separation. Surgeons have the most difficulty in deciding about surgery for Type III injuries. The loss of contact between the clavicle and the acromion means that motion is going to be altered. If a rehab program isn’t enough to successfully treat this injury, then surgery is done to reconstruct the joint.
Sometimes individual patient demands require surgery early on. And in the case of a chronically dislocating AC joint, surgical intervention may be the only way to restore full, normal stability and movement.
Overhead athletes and heavy manual laborers seem to fall into this group most often. And there’s some question that maybe patients with type III injuries fail because they didn’t complete their rehab program or the rehab program wasn’t quite enough. The shoulder can function normally without an intact clavicle. But it cannot do so when the shoulder muscles are weak and unable to stabilize the joint.
You can always complete a rehab program before making this decision. Then, if the shoulder is still unstable, then surgery can be done. The best evidence suggests if you are going to take the conservative (nonoperative) approach, then give it your best and make sure you complete the rehab program. The therapist will test your strength before releasing you on your own. Any painful symptoms, clicking, or other signs of instability should be reviewed by your orthopedic surgeon.