What is the AC Joint?
The AC (Acromio-clavicular) joint is a thick fibrous joint connecting the top of the shoulder blade to the outer end of the collarbone. Essential for weight-bearing force transfer from the upper limb to the skeleton, this joint is reinforced by three major ligaments: Acromioclavicular, Corococlavicular, and Corocoacromial.
How Do AC Joint Injuries Occur?
The primary injury mechanism involves a force separating the shoulder from the collarbone, typically directed downward. Common causes include ground falls where the shoulder’s top impacts first, rugby tackles, or falls onto an outstretched hand. AC joint injuries have varying severity levels and are classified using specific grading systems.
Identifying Symptoms of AC Joint Injury
Post-injury symptoms include immediate shoulder-top pain, swelling, bruising, and movement loss. Weight-bearing or carrying heavy objects might exacerbate the pain. In severe instances, a ‘step deformity’—a noticeable height difference between the shoulder top and collarbone—may appear. Pain is also common when reaching across the body, like while fastening a seatbelt.
Physiotherapists can conduct clinical tests to confirm the diagnosis, with X-rays assisting in injury severity grading. The injury classification, provided by a physiotherapist or doctor, is essential for determining the best treatment approach. Lower grade classifications indicate fewer torn ligament fibres, while higher grades often necessitate surgical intervention.
The Role of Physiotherapy in Treatment
Physiotherapy aims to support natural joint healing while maintaining shoulder girdle strength and movement. Initial measures include joint support, potentially requiring a sling, brace, or supportive taping. Most AC joint sprains heal within six weeks, but subsequent shoulder issues aren’t uncommon, emphasizing a comprehensive rehabilitation program’s importance. Surgery might be recommended for severe sprains or potential fractures, but post-surgery also requires proper rehabilitation.
Note: This article’s information isn’t a substitute for professional medical advice. Always consult a medical professional about your specific condition.