Separated shoulder
A separated shoulder, also known as acromioclavicular joint injury, is a common injury to the acromioclavicular joint. The AC joint is located at the outer end of the clavicle where it attaches to the acromion of the scapula. Symptoms include non-radiating pain which may make it difficult to move the shoulder. The presence of swelling or bruising and a deformity in the shoulder is also common depending on how severe the dislocation is.
| Separated shoulder | |
|---|---|
| Other names | Acromioclavicular joint injury, acromioclavicular separation, AC joint separation, AC separation |
| An Xray showing a separated shoulder. Notice the separation between the end of the collarbone and the scapula. | |
| Specialty | Orthopedics, emergency medicine |
| Symptoms | Pain, deformity, decreased range of motion |
| Types | Type I, II, III, IV, V, VI |
| Causes | Trauma such as a fall |
| Risk factors | Contact sports |
| Diagnostic method | Examination, X-rays |
| Differential diagnosis | Dislocated shoulder, clavicle fracture |
| Treatment | Type I and II: Sling and pain medication Type III: Conservative management and surgery if still symptoms Type IV, V, VI: Surgery |
| Frequency | Relatively common |
It is most commonly due to a fall onto the front and upper part of the shoulder when the arm is by the side. They are classified as type I, II, III, IV, V, or VI with the higher the number the more severe the injury. Diagnosis is typically based on physical examination and X-rays. In type I and II injuries there is minimal deformity while in a type III injury the deformity resolves upon lifting the arm upwards. In type IV, V, and VI the deformity does not resolve with lifting the arm.
Generally types I and II are treated without surgery, while type III may be treated with or without surgery, and types IV, V, and VI are treated with surgery. For type I and II treatment is usually with a sling and pain medications for a week or two. In type III injuries surgery is generally only done if symptoms remain following treatment without surgery.
A separated shoulder is a common injury among those involved in sports, especially contact sports. It makes up about half of shoulder injuries among those who play hockey, football, and rugby. Those affected are typically 20 to 30 years old. Males are more often affected than females. The injury was initially classified in 1967 with the current classification from 1984.