Acromio-clavicular (AC) joint separation or shoulder separation results from a traumatic injury to the ligaments that keep the shoulder blade (scapula) and collarbone (clavicle) together. This is usually the result of injury during contact sports by receiving a direct blow to the shoulder or during a fall that resulted in direct impact to the joint. The resulting injury can vary from a sprain to a complete tear, varying in severity of symptoms, but it can be very painful at onset and should be evaluated by a professional. Due to the nature of the injury, those at increased risk will be athletes, especially if participating in contact sports or sports prone to falls (ex. gymnastics, skiing).
Diagnosis is based on physical presentation and imaging studies (X-rays).Patients may experience shoulder pain, shoulder or arm weakness, bruising, swelling, change in range of motion, and a protuberance over the site of injury.To classify the severity and thus assist in diagnosing, the Rockwood classification system is used. This is a system that ranges from type I to VI, and it is used to describe the possible damage present to the soft tissue. This classification looks at the AC ligament, CC ligament, Joint capsule, deltoid muscle, trapezius muscle and the position of the clavicle relative to normal anatomy. Types I – III are the most common, types IV – VI are very rare and more likely to require surgery due to the severe damage to the surrounding ligaments and structures.
Shoulder separation is most commonly managed conservatively with the use of anti-inflammatory medication, ice to the site, physical therapy and rest. The timeline for recovery ranges from days to 12 weeks; this will depend on patients age, ability to modify activity and everyday physical demands that they might have. Surgery is rarely required.
