Acromioclavicular (AC) joint injury refers to as shoulder separation and not shoulder dislocation. Your AC joint is the joint between the shoulder and your scapula and clavicle. It allows your arm to transmit forces to the rest of your body during activities such as lifting, pushing and pulling. Body ligaments stabilize your AC joint. An AC joint sprain refers to an injury caused by overstretching of the ligaments that support the acromioclavicular joint. The degree of damage can vary from a mild strain to a complete ligament deformity.
Causes of an AC Joint Injury
Collision with a solid object or surface can injure your AC joint. A fall from a bicycle or on the football pitch where the shoulder hits the ground can damage your AC joint. It could also get injured if you fall on an outstretched arm. The contact force transmits up through your arm, forcing your clavicle and acromion to separate. In the process, the ligaments overstretch and become damaged.
Your physiotherapist will suspect AC joint sprain when you report:
- Swelling on your shoulders
- Pain on the top of your shoulder after heavy lifting
- Loss of shoulder movement
- Visible lump on the top of your shoulder
Physiotherapists grade AC joint injury by severity from Grade I to Grade III. A more severe AC joint injury is graded as Grade III. You may even see or feel a bump at the tip of your shoulder bones after the separation of your AC joint. In such a case, your physiotherapist should perform X-rays to ensure your bones don’t fracture. His explanation and guidance will quicken your recovery.
Treatment of AC Joint Injury
Acromioclavicular joint injury patients often start to feel better a few days after the accident. Nonetheless, it takes at least six weeks for your ligament to heal. As such, it’s essential to protect your immature scar tissue from overstretching. You can use a shoulder brace, taping, or sling to de-load your AC joint. Physiotherapy will help you to improve your upper limb proprioception, reduce inflammation and pain, minimize your chances of re-injury, and improve your shoulder alignment.
In the case of severe injuries, you may choose to undergo AC joint surgery to repair your damaged ligaments and join the AC joint. One of the most critical aspects of surgery is post-operative rehabilitation. Guidance from an experienced shoulder physiotherapist will quicken your recovery. Post-operative rehabilitation aids in restoring your shoulder strength, endurance, and motion. You will also require individualized functional-based restraining and proprioception to recover quickly. Nonetheless, surgery subjects you to risks such as stiffness, infection, persistent instability, and difficulty to get back to your previous state.
Returning to Sports after AC Joint Injury
It’s wise to undergo a graduated transition before returning to sports to avoid the risk of injury recurrence. It includes the completion of an individualized rehabilitation program aimed at improving proprioception and strength of your upper limbs. Disruption of the acromioclavicular joint is referred to as a shoulder separation and can cause deformity.