AC JOINT INJURIES
The AC joint (or technically the acromio-clavicular joint) is the joint between the clavicle (collarbone) and the acromion (top of your shoulder blade). It can be felt as the small bump near the edge of your shoulder. The AC joint is a common site of injury in contact sports such as football or rugby, or in people falling onto the point of their shoulder.
There is a huge variety in the severity of these injuries. Some can heal themselves, and can see athletes returning to their sport of choice in only a few weeks, while others will require surgery, followed by months of rehabilitation. This will depend on the grade of the injury.
AC joint injuries are separated into 6 grades:
Grade 1: Small sprain of the surrounding ligaments. It will be tender to touch, and movement will be painful.
Grade 2: A larger sprain of the surrounding ligaments, with a slight displacement of the joint. A small bump or step up on the top of the shoulder may be visible.
Grade 3: A complete tear of the surrounding ligaments. An obvious displacement of the joint will be seen on the shoulder.
*These injuries are generally managed with a sling initially as the ligaments heal (for anywhere from 1-2 days for a minor Grade 1, to 6 weeks for a Grade 3). Strengthening of the shoulder and surrounding musculature is vital prior to a return to sport.*
Grade 4: Like a grade 3, but the collarbone is pushed back behind the joint.
Grade 5: Like a grade 3, but with an even greater bump or step up on the shoulder (huge abnormality will be clearly visible).
Grade 6: Like a grade 3/5, but the collarbone is pushed below the shoulder.
*These injuries (as well as some severe grade 3 injuries) will require surgery, followed by extensive rehabilitation*
Chris Bryceson
B. Health Sciences (Physio), APAM
CB Physiotherapy