AC joint repaired with a hook plate

 

AC Joint- Separated Shoulder

 

The acromio-clavicular or "AC joint" spans the end of the clavicle and the acromion on the lateral side of the shoulder.  Injury occurs from direct impact on the shoulder, typically in bicycling injuries.  They are classified based on the direction and magnitude of the dislocation and are commonly referred to as a “separated shoulder”.  Low grade dislocations heal uneventfully with rest and immobilization.  High grade separations with complete dislocation of the clavicle present with marked deformity at the joint.  Historically these injuries have been problematic because of the inability to maintain alignment of the joint.  Newer surgical techniques and implants allow more of these injuries to be repaired with good cosmetic and functional results. 

 

If the end of the collar bone is fractured as well as an AC joint separation, then my surgical protocol employs a hook plate which spans the lateral aspect of the clavicle and ‘hooks’ under the acromion. I have included a link to the surgical technique guide below.   This technique works well clinically and the plate is able to hold the joint well reduced.  The problem with these plates, however, is that they irritate the rotator cuff tendons especially with overhead movements.  I recommend that all patients undergoing surgical repair to expect to have the plate removed at 3-6 months after repair to alleviate rotator cuff irritation.

 

Hook Plate Technique Guide

 

In cases where the end of the clavicle is not fractured, I have been using a device called a Tightrope which is made by Arthrex.  I have included a link to the technique guide below.  This device essentially recreates the ligaments that span the space between the coracoid and clavicle.  The surgery uses a slightly larger incision to protect the nerves that run close to the coracoid and prevent them from being injured.  The advantage of this technique is that patients don't have to have a second surgery to remove the fixation and they don't have discomfort around the fixation device.  I prefer to use this device rather than a plate when I can and most of the patients with this device implanted are very happy with the cosmetic and functional outcome.

 

 

Tightrope fixation of the AC joint

 

Tightrope Technique Guide

 

 

 

 

 

            

                    Grade III Separation of the Left AC joint             AC separation after repair using Tightrope

 

 

 

 

 

Both the Hook Plate and Tightrope work well with a good functional and cosmetic outcome.  There have been reports of failure with both types of fixation and this is dependent on factors such as the quality of the bone, the length of time between injury and surgery and smoking-which significantly increases the rate of failure of the implant. 

 

The surgery to repair the AC joint is done as an outpatient, meaning that you don't have to stay overnight in the hospital and can go home the same day as the procedure is done.  The surgery takes about an hour and most patients report mild to moderate pain that requires pain medication for the first 2 weeks.  I keep patients in a sling for the first 2 weeks after surgery and the rehab is similar to a subacromial decompression.  Click on the link below to see my post-op surgery protocol.   I don't allow patients to return to competitive athletics for 3-4 months after the surgery to avoid re-injury.  I have included a link to my post-operative shoulder protocol to give you an idea of what to expect after surgery and to answer basic questions that you may overlook or forget to ask when you are in the office.

 

Post op Shoulder Protocol