An acromioclavicular (AC) joint injury is referred to as “shoulder separation, ” and it is not shoulder dislocation. AC joint is the joint at the shoulder top in between the collarbone (clavicle) and the shoulder blade (scapula). It is important in allowing overhead movements and transmits forces from the arm to the rest of the body while pulling, pushing or lifting.
The AC joint injury occurs when the ligaments supporting the AC joint are overstretched. The degree of damage varies from a mild strain of a single to multiple ligaments to complete ligament injuries and deformities.
AC joint injuries will result from
- Collision to solid objects or surfaces
- Falls from bicycles
- Sports activities where the shoulder hits the ground.
- Falls on an outstretched arm
Symptoms of AC joint injuries
- Swelling and bruising
- Lack of shoulder movement
- Pain on the shoulder top that is aggravated by overhead movements and heavy lifting
- A hard and visible lump may also develop on the shoulder top indicating the displacement of the collar bone
- AC joint injury is graded based on the severity as Grade I (minimal injury) to Grade III (severe injury).
Treatment and management
- The primary aim of the treatment is to control the symptoms by modifying your everyday activities so the condition is not aggravated.
- Ice compress reduces the pain and inflammation
- Medications such as NSAIDs (aspirin) and analgesics (Tylenol) reduce the pain
- Cortisone injections in severe cases
- Immobilization of the arm using a sling
Arthroscopic surgery is recommended if the above non-surgical measures do not help. Grade I and II rarely need surgeries. Grade III injuries also return to normal position with a few restricted movements. In the case of a painful lump, partial clavicle excision is done.