A separated shoulder is not actually an injury to the shoulder joint. Instead, the injury involves the acromioclavicular joint (AC joint).
The shoulder is made up of three bones: the upper arm bone (humerus), the shoulder blade (scapula) and the collarbone (clavicle). The shoulder is a ball-and-socket joint, which means the ball of the upper arm fits into a shallow socket in your shoulder blade. The AC joint is where the collarbone meets the highest point of the shoulder blade (acromion).
Most commonly, shoulder separations are caused from a fall directly onto the shoulder. The fall injures the ligaments that surround and stabilize the AC joint.
If the force is severe, the ligaments attaching to the underside of the clavicle are torn. This is what causes the separation of the collarbone and acromion. The acromion actually moves downward from the weight of the arm and creates a bump or bulge about the shoulder.
- A mild separation involves a sprain of the AC ligament that does not move the collarbone and looks normal on X-rays.
- A more serious injury tears the AC ligament and sprains or slightly tears the coracoclavicular (CC) ligament, putting the collarbone out of alignment.
- The most severe separation completely tears both the AC and CC ligaments and puts the AC joint noticeably out of position.
Symptoms of a separated shoulder
- Bump or bulge above the shoulder
- Injury can range from a little change in configuration with mild pain to noticeably deformed and very painful
Separated shoulder treatment
Nonsurgical options include:
- Shoulder sling
- Cold packs
Surgical Treatment: Surgery may be necessary if your pain is persistent and deformity is severe.
For more severe injuries of the AC joint where the coracoclavicular ligaments are torn surgery can be done to reconstruct these. Both open and arthroscopic procedures are available. A variety of different fixation devices are now commonly used that involve high strength sutures tied over metal buttons. In more chronic injuries soft tissue grafts are also incorporated in the reconstruction. This reduces the clavicle back down so it is in line with the acromion.