Shoulder conditions
AC joint injuries
Sprains, separations, and arthritis of the joint where the collarbone meets the shoulder blade, felt as pain right at the top of the shoulder.
Top-of-shoulder joint
Common in falls & sport
Often heals without surgery
What is an AC joint injury?
The acromioclavicular (AC) joint sits at the very top of the shoulder, where the end of the collarbone meets the shoulder blade. Injuries range from a mild sprain to a full separation where the ligaments tear and the collarbone lifts up.
Over time the AC joint can also develop arthritis, causing pain with reaching across the body and lifting. Most separations are treated without surgery, while higher-grade injuries and painful arthritis sometimes need a procedure.
Overview
At a glance
Most settle on their own
The majority of AC joint sprains and separations heal well with simple supportive care, even when a visible bump remains.
Symptoms & signs
How an AC injury feels
Pain is pinpointed to the top of the shoulder.
Pain right at the top of the shoulder, over the joint
A visible bump or step-off where the collarbone rises
Pain reaching across the body or lifting overhead
Tenderness directly over the AC joint
Pain lying on the affected side
Causes & risk factors
What causes them
Direct trauma is the usual cause; wear causes arthritis later.
A fall onto the shoulder
Landing directly on the point of the shoulder separates the joint.
Contact sport
Collisions in football, hockey, and cycling are common causes.
Repetitive loading
Heavy lifting and overhead work can wear the joint over time.
Age-related wear
Arthritis of the AC joint develops gradually with use.
Treatment options
How AC injuries are treated
Most are managed without surgery; persistent cases may need a procedure.
- A sling for comfort while the ligaments settle
- Ice and anti-inflammatory medication
- A gradual return to motion and strengthening
- An injection for painful AC arthritis
- Removing the arthritic end of the collarbone for joint pain
- Reconstructing torn ligaments for high-grade separations
- Restores comfort and a stable shoulder
- Reserved for severe or persistent cases
Related procedure
For severe separations or persistent arthritis, surgery may be the answer, see how AC joint repair works.
Recovery
What recovery looks like
Most injuries recover steadily over several weeks.
Protect
A sling rests the joint and controls early pain.
Restore motion
Gentle motion and therapy return reach and comfort.
Strengthen
Progressive strengthening rebuilds the shoulder.
Staged return
If surgery is done, return to sport is staged over a few months.
FAQ
Common questions
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Often a small bump remains even after a separation heals, but it usually causes no problem and does not require surgery.
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Most separations heal well without surgery. Higher-grade separations and persistently painful joints are the ones that may benefit from a procedure.
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Activity changes, anti-inflammatories, and injections help most people. If pain persists, removing the worn end of the collarbone is very effective.
Related procedures