• Instability of the acromioclavicular joint (ACJ) usually occurs as a result of ‘high-energy’ trauma
• Depending on the degree of instabilty treatment may require physiotherapy with or without surgical intervention
• Early surgery aims to allow the ligaments torn during the dislocation to heal
• Surgical reconstruction can be performed later using either synthetic materials or tendon grafts
• Cases can be performed using open or arthroscopic (keyhole) surgical procedures

When is surgery required ?

The majority of injuries to the acromioclavicular joint (ACJ), which lies between the outer end of the collar bone (clavicle) and part of the the shoulder blade (scapula) called the acromion, are  sprains. These normally occur after a fall or tackle where the structures that normally control the joints stability are loaded and partially torn. Most sprains although painful will settle with time, applied ice and physiotherapy to rehabilitate the injured area. If these structures are completely disrupted and the joint is rendered unstable, early surgery may be required. In some cases of longstanding instability of the joint reconstructive surgery may be required to restore more normal relationships between the scapula and clavicle.

X-ray of an acute ACJ dislocation

What structures are damaged in ACJ instability ?

The ACJ relies for stability on tough fibres surrounding the joint (capsule) and on two ligaments running between part of the shoulder blade called the coracoid and the clavicle (coronoid and trapezoid). Complete disruption of all three structures will result in instability.

What treatments are available for ACJ instability ?

The appropriate treatment choice is dependant on a number of factors including the degree of instability. How recently the injury occurred, the patterns of structures injured and the anticipated level of activity that the individual wishes to undertake, all have an impact on the appropriate treatment options.

X-Ray following an acute (early) ACJ reconstruction

Most surgeons would agree that with sprains or minor injuries that surgery is inappropriate. Where significant disruption has occurred the options lie between early intervention (preferably within the first 2 weeks) using either open or arthroscopic (keyhole) surgery or an initial non-operative approach and then review to see whether the individual is symptomatic or needs to have a delayed reconstruction.