What is a separated shoulder and does it require surgery?
An acromioclavicular (AC) joint injury is often called a separated shoulder. This is somewhat of a misnomer as the ball and socket of the shoulder joint itself is not injured. Rather, there is disruption of the AC joint where the collarbone (or clavicle) and the highest point of the shoulder blade (the acromion) meet. In AC joint injuries, the ligaments that hold these two bones aligned are torn to varying degrees.
AC joint injuries represent nearly 50 percent of all athletic shoulder injuries. They usually result from a fall onto the tip of the shoulder. I see it in mountain bikers, snowboarders and skiers fairly often. I suffered one myself when I fell off my mountain bike several years ago.
Following these injuries, patients experience pain, swelling and a bump on top of their shoulder which varies in size based on the type of injury. Orthopedists classify these injuries as Type 1-6 with Type 1 being the least severe. Unlike most ligamentous injuries, such as an ACL or MCL tear of the knee, orthopedists depend primarily on X-ray findings and less so on a physical exam to decide what type of AC joint injury a patient sustained.
Type 1 and 2 injuries are less severe disruptions of the AC joint and are treated without surgery. A sling for one to two weeks is recommended to help relieve stress on the injured ligaments and help decrease pain. Following this, a rehabilitation program is started to restore shoulder range of motion and strength. Patients may be left with a small bump over the end of their collarbone the rest of their life, but most go on to regain full shoulder range of motion and are able to resume all activities without pain. A small percentage of these patients can have persistent pain that later necessitates surgery.
Type 4, 5 and 6 injuries are high-energy injuries with severe displacement of the end of the collarbone in relationship to the shoulder blade. There is disruption of not only the AC joint ligaments but also the coracoclavicular (CC) ligaments. For these type of injuries, surgery is always recommended. Without surgery, most patients experience chronic pain and shoulder weakness.
In Type 3 injuries, the AC joint is dislocated with the collarbone being 100 percent displaced superiorly in relationship to the acromion. The AC joint can be reduced back into alignment by placing an upward force on the arm. Treatment of Type 3 injuries are the most controversial with some sports medicine orthopedists recommending immediate surgery while others recommend a wait and see approach. In my own practice, I tend to recommend that patients wait and rehabilitate their shoulder for two months. At two months, most are doing well and do not require surgery. However, I do recommend immediate surgery for patients with Type 3 injuries if they are younger, do a lot of overhead work or heavy labor (i.e. carpentry) or are an overhead athlete (i.e. tennis), as without surgery, they may experience some chronic pain and lose some strength and endurance. Moreover, there are now some newer arthroscopic techniques that are minimally invasive that can be used to fix Type 3 injuries fairly predictably.
If patients present months or years later with a painful Type 3-6 AC joint injury, the surgery is then more involved as there is a lot of scarring. In these cases, I perform an AC joint reconstruction utilizing a donor tendon to reconstruct the chronically torn ligaments and realign the AC joint. Following this, patients are in a sling for six weeks and are quite limited in their activities for three months.
Dr. Rick Cunningham is a Knee and Shoulder Sports Medicine Specialist with Vail-Summit Orthopaedics. He is a physician for the US Ski Team and Chief of Surgery at Vail Valley Medical Center. Do you have a sports medicine question you’d like him to answer in this column? Visit his website at www.vailknee.com to submit your topic idea. For more information about Vail-Summit Orthopaedics, visit www.vsortho.com.