Question 1

What is the AC joint and what does it do?

Accepted Answer

The AC joint (acromioclavicular joint) is where your collarbone (clavicle) meets the highest point of your shoulder blade (acromion). It's the bump you can feel at the top of your shoulder. This small joint allows your shoulder blade to move smoothly when you raise your arm. It's held together by strong ligaments. When these ligaments are sprained or torn, the collarbone separates from the shoulder blade, creating what's commonly called a 'separated shoulder.' This is different from a 'dislocated shoulder,' which involves the ball-and-socket joint lower down.

Question 2

What are the different types or grades of AC joint injuries?

Accepted Answer

AC joint injuries are graded Type I through VI based on severity. Type I is a mild sprain with no separation - ligaments are stretched but not torn. Type II is a partial separation with one ligament torn. Type III is a complete separation with both main ligaments torn and the collarbone sitting higher. Types IV, V, and VI are severe injuries with the collarbone displaced in different directions. Most injuries are Type I or II (treated non-surgically) or Type III (controversial - some treat non-surgically, some surgically). Types IV-VI usually require surgery. Your doctor uses X-rays to determine your type.

Question 3

What's the difference between a separated shoulder and a dislocated shoulder?

Accepted Answer

This confuses many people. A separated shoulder is an AC joint injury - the collarbone separates from the top of the shoulder blade at the bump on top of your shoulder. A dislocated shoulder is when the ball of your upper arm pops out of the socket lower down in your shoulder. They're completely different injuries in different locations. AC separations usually result from falling directly onto the point of the shoulder, while shoulder dislocations typically happen when the arm is forced into an awkward position. AC separations usually don't require emergency treatment, whereas shoulder dislocations need urgent reduction (putting the ball back in the socket).

Question 4

Will the bump on my shoulder go away?

Accepted Answer

With non-surgical treatment of Type III and higher injuries, the visible bump usually remains permanently, though it often becomes less prominent over time as swelling resolves. The bump is your collarbone sitting higher than normal because the ligaments holding it down are torn. Many people find this cosmetically bothersome initially but adapt to it. The bump doesn't necessarily mean you'll have pain or problems. For Type I and II injuries, there's typically no permanent visible bump. If the appearance really bothers you, surgical reconstruction can eliminate the bump, but surgery is generally not recommended for cosmetic reasons alone.

Question 5

Should I have surgery for a Type III AC separation?

Accepted Answer

This is the most controversial question in AC joint injuries. Research shows that most people with Type III injuries do well with non-surgical treatment and physiotherapy. However, some surgeons recommend surgery for young athletes, manual laborers, or overhead workers. The decision depends on your age, activity level, occupation, and whether you're willing to accept a visible bump. If you're an office worker who plays recreational sports, non-surgical treatment is usually best. If you're a 25-year-old carpenter or competitive athlete, surgery might be considered. There's no definitively 'right' answer - discuss your specific situation with your surgeon. You can always try non-surgical treatment first and have surgery later if problems develop.

Medical Disclaimer

Separated Shoulder (AC Joint Injury)

📖What is Separated Shoulder (AC Joint Injury)?

🔬What Causes It?

⚠️Risk Factors

You may be at higher risk if:

🛡️Prevention