Separated shoulder
A common shoulder injury classified into six types.
A separated shoulder, medically termed an acromioclavicular joint injury, affects the joint where the outer end of the collarbone meets the acromion of the shoulder blade. Symptoms include pain that does not radiate and can make moving the shoulder difficult, along with possible swelling, bruising, and a visible deformity depending on the injury's severity. The most common cause is a fall directly onto the front and upper part of the shoulder while the arm is at the side.
The injury is classified into six types (I through VI), with higher numbers indicating more severe damage. Diagnosis typically relies on a physical exam and X-rays. In type I and II injuries, there is minimal deformity; in type III, the deformity becomes more prominent when the arm is lifted upward. For types IV, V, and VI, the deformity persists with arm elevation.
Treatment varies by type. Types I and II are managed without surgery, usually with a sling and pain medication for one to two weeks. Type III may be treated with or without surgery, with surgery generally considered only if symptoms persist after non-surgical treatment. Types IV, V, and VI require surgery.
This injury is common in sports, especially contact sports like hockey, football, and rugby, where it accounts for about 10-20% of shoulder injuries depending on the sport. It most often affects males between 20 and 30 years old. The initial classification system was established in 1967, with the current system dating from 1984.
The separation occurs when the acromion of the scapula, connected to the clavicle by the superior acromioclavicular ligament and the coracoclavicular ligaments (trapezoid and conoid), is disrupted. Four types of soft tissue damage can cause it: tearing of the conoid or trapezoid ligaments at any point, upward displacement of the lateral clavicle after being pulled from its periosteum, tearing of the acromioclavicular ligaments, or avulsion of the conoid-trapezoid ligament origin from the coracoid.
Diagnosis involves physical examination and X-ray. A physical exam can reveal point tenderness, pain at the AC joint during cross-arm adduction (arm raised to 90°, elbow bent to 90°, then moved across the chest), and pain relief with a local anesthetic injection.
Quick Facts
- Field
- Orthopedics, emergency medicine
- Symptoms
- Pain, deformity, decreased range of motion
- Types
- Type I, II, III, IV, V, VI
- Causes
- Trauma such as a fall
- Risks
- Contact sports
- Diagnosis
- Examination, X-rays
- Differential
- 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
Facts from the source article.
Lore & Background
The injury is most commonly due to a fall onto the front and upper part of the shoulder when the arm is by the side. It is 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 becomes more prominent upon lifting the arm upwards. In type IV, V, and VI the deformity does not resolve with lifting the arm.
A separated shoulder is a common injury among those involved in sports, especially contact sports. It makes up about 10-20% 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.
Type VI is extremely rare and generally only involved with motor vehicle collisions, falls from height, or severe sports impacts.
Reader's Guide
A separated shoulder is a common injury, particularly in contact sports such as hockey, football, and rugby, and affects males more often than females, typically between ages 20 and 30. The injury is classified into six types, with types I and II being mild and often treated without surgery, while types IV, V, and VI require surgery. Type III injuries may be treated with or without surgery, with surgery generally reserved for persistent symptoms. The classification system was initially established in 1967 and updated in 1984. Diagnosis relies on physical examination and X-rays, with the acromioclavicular joint space normally 5 to 8 mm. Treatment begins with rest, ice, and anti-inflammatories, followed by sling immobilization and physical therapy for mild cases. The injury can lead to permanent deformity, such as a bump on the shoulder in type II and III injuries. Long-term outcomes for type III injuries show that non-surgical treatment is often as good as or better than surgery, though the body may remodel the joint over time.
Did You Know?
- A separated shoulder is also known as acromioclavicular joint injury.
- The injury was initially classified in 1967, with the current classification from 1984.
- In type II injuries, the bump on the shoulder is permanent.
More in Dislocations, sprains and strains 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced