Acromioclavicular Joint Injury

What is it?

An AC (acromioclavicular) joint injury or separation is when the collarbone separates from the shoulder blade due to damage to the ligament that holds them together.

The acromioclavicular (AC) joint allows you to perform overhead movements with your arm and pulling, lifting or pushing objects.

Acromioclavicular joint injury

What causes it?

An AC joint injury occurs due to one of the following:

  • Trauma (after a direct blow or fall to that area).
  • Overuse during repeated overhead, pulling, pushing or lifting movements.

Many people who play sports are at risk of developing an AC joint injury due to the high chance of falling during practice or a sports competition


The symptoms of an AC joint injury depend on the severity. However, these are some of the complaints of people with this injury:

  • Shoulder pain and swelling.
  • Loss of shoulder movement and strength, meaning you cannot lift your arm.
  • A visible bump above the shoulder.
  • Difficulty with sleeping on the injured side due to pain.


  • Several Questions Will Be Asked About The Injury/Pain (Cause, Location, Intensity, Aggravators/Relievers).
  • A Few Simple Tests Can Be Done To See The Strength And Movement Of The Shoulder Joint.

Sometimes, a doctor may request a scan to confirm the diagnosis and determine the severity of the injury.

Acromioclavicular joint injury


  • Anti-inflammatory medications to reduce inflammation and pain.
  • Apply ice immediately after the injury.
  • Rest the injured arm.
  • Use a shoulder sling to minimise shoulder movement.
  • Physiotherapy treatment to improve shoulder strength and prevent stiffness.
  • Surgery (severe cases).

Tips and tricks for managing daily activities

  • Keep Your Shoulder Immobilised When Completing Activities That Involve The Arms.
  • Routinely Do The AC Joint Injury Exercises Recommended By Your Physiotherapist.


When you experience any pain during overhead arm movements (at home, work or sport), visit your doctor immediately to have it assessed.

Wearing a brace or support when doing intense activities such as football helps keep the joint in place and reduces any damage caused during a tackle or when you fall.

How long till I get better

Research suggests that ligaments require at least six weeks to three months to heal. However, most patients notice more flexibility in the AC joint even one year after injury.

For all your AC joint needs, feel free to give us a call on 02 9793 8840 or Book Online