Shoulder Separation (AC Joint Injury)

Medical term: Acromioclavicular Joint Separation

Overview

A shoulder separation is an injury to the acromioclavicular (AC) joint, the point where the collarbone meets the highest part of the shoulder blade. This injury is most often caused by a direct fall onto the shoulder, commonly seen in contact sports, cycling accidents, and falls. AC joint injuries are graded from mild sprains (Grade I) to complete ligament tears with significant displacement (Grade V-VI).

Our San Diego orthopedic team treats shoulder separations across all severity levels. Lower-grade injuries typically respond well to rest, ice, a sling, and guided physical therapy. Higher-grade separations that result in significant instability or persistent pain may benefit from surgical reconstruction to restore normal shoulder mechanics and strength.

Frequently Asked Questions

What is the difference between a shoulder separation and a shoulder dislocation?

A shoulder separation involves the joint where the collarbone meets the shoulder blade (the AC joint), while a shoulder dislocation occurs when the upper arm bone comes out of the shoulder socket. They are distinct injuries with different treatment approaches.

Will the bump on my shoulder go away?

In mild to moderate separations, the bump may diminish over time but often remains slightly visible. This cosmetic change does not usually affect shoulder function once the joint has healed.