AC Joint Reconstruction Surgery

A separated shoulder happens when you injure ligaments around the acromioclavicular (AC) joint. This is where the collarbone, or clavicle, meets the highest point of the shoulder blade. In severe cases, the collarbone may separate from its normal attachment from the shoulder blade.

Often confused with a shoulder dislocation, shoulder separation is a different injury. People who have a shoulder separation may notice a bump or pain on top of their shoulders. The bump is caused by the end of the collarbone pushing up against the skin.

This article discusses the different types of separated shoulder injuries and when they require surgery. It also covers the different types of surgery available for a separated shoulder.

Types of Separated Shoulder Injuries

There are different types of separated shoulders. They're classified by how severe the injury is and how many ligaments are involved. The two types of ligaments that hold the collar bone to the shoulder are acromioclavicular (AC) ligaments and coracoclavicular (CC) ligaments.

The types of separated shoulder injuries are:

• Type I: The AC ligaments have a sprain or partial tear. It may have tenderness and mild swelling in the AC joint. Usually, these heal in a few weeks.
• Type II: The AC ligaments are completely torn. The CC ligaments have a sprain or partial tear. The AC joint usually feels tender and is swollen.
• Type III: The AC ligaments and CC ligaments are completely torn. The AC joint looks abnormal and swollen. Injuries can take up to a few months to heal.
• Type IV, V, and VI: These are the most severe and require surgery.

Most of the time, you can manage separated shoulder injuries with non-invasive treatments. This may include supporting your shoulder with a sling, applying cold packs, and taking over-the-counter pain medication.

Type I and type II separations can be managed without surgery. These types of separations are by far the most common. Surgical intervention is considered only in a small fraction of these injuries.

For type III injuries, doctors may disagree on treatment, with some recommending non-invasive treatment and some recommending surgery.

In general, the most severe types of separated shoulders need surgery for treatment. Most type IV, V, and VI shoulder separations do better with surgery.

Surgical Treatment Options

The goal of surgery is to realign the end of the collarbone with the outer edge of the shoulder blade (the acromion).

The surgery should also ensure that the bones are stable as well as relieve pain at the AC joint.

The primary surgical options include repairing the AC joint, holding the collarbone down, or reconstructing ligaments.

Repairing the AC Joint

Because the joint is noticeably out of place, aligning and holding it in the proper position is important.

One method is using Kirschner wires (K-wires) to hold the AC joint in place. However, some complications can occur if the K-wire becomes loose. For example, there have been reports of K-wires placed in the clavicle moving to other structures over time, including the chest cavity.

Some experts suggest that if K-wires are used, the surgical site be monitored by radiography every four weeks. The K-wire should be removed immediately if there are any signs of loosening.

Another downside of this surgery is that it doesn't correct the damage to the strong ligaments that hold the end of the clavicle down. In addition, these metal implants used to hold the joint in position can cause pain, and they may need to be removed.

Holding the Collarbone Down

There are several techniques to address AC joint injuries that hold the collarbone down. Some use metal and others use heavy sutures.

Most often the collarbone is held to the coracoid process, a hook of bone in the front of the shoulder that is just below the collarbone. Either a screw can be put from the collarbone into the coracoid, or the two bones can be wrapped together tightly with sutures.

The downside of these techniques is that screws generally have to be removed after healing. In addition, sutures can cut through and fracture the bone.

Another alternative to these methods is a button suture. Two metal buttons are placed—one behind the clavicle and the other behind the coracoid. A suture serves as a CC ligament.

Reconstructing Ligaments

Another category of surgery is reconstructing the ligaments that hold the end of the clavicle in the proper position.

There are a number of options for this procedure, either using your tissue or donor tissue. One of the most commonly performed procedures is a Weaver-Dunn surgery. This surgery shifts one of the major ligaments that attach to the acromion over to the end of the clavicle. This holds the clavicle in its normal position.

Other options include reconstruction of the CC ligaments that were torn when the shoulder separation injury occurred. This can be with a tendon from your leg or a tendon from a donor. The tendon graft is wrapped around the hooked coracoid and then into the clavicle.

Summary

Most cases of separated shoulder heal with rest, cold packs, and over-the-counter pain medication. For severe injuries, your physician may recommend surgery to help the injury heal. Surgery may include using screws, sutures, or K-wire to hold the bones in place. It may also involve reconstructing ligaments with your own tissue or donor tissue.

A Word From Verywell

Different surgeons have success with various treatment options. Just because one surgeon prefers a particular treatment does not mean it is the best. Well-regarded surgeons argue over these very issues and may disagree about which option is the best. Make sure you find a surgeon who has experience with the surgical treatment of a separated shoulder when you make your decision.