To understand how to classify acromioclavicular (AC) joint injuries utilising the Rockwood system. To explore the use of novel imaging techniques to help improve the accuracy of classifying AC joint injuries using this system.

The Rockwood classification system of AC joint injury was introduced in 1984, which graded AC joint injuries into six categories.(1, 2) Current best practice of AC joint injury management is based on this system.(3) Patients are either conservatively or surgically managed depending on what class of AC joint injury they are diagnosed with.(4, 5) Classes I-II are managed conservatively, classes IV-VI are managed surgically and class III injuries are managed on a case-by-case basis. Research into the accuracy of AC joint injury classification has shown...

Tossy et al initially classified AC joint injuries into three categories in 1963. This classification was primarily based on the degree of damage and/or rupture of the acromioclavicular (AC) and coracoclavicular (CC) ligaments. Rockwood retained these three categories and modified the third category into a further three that were more specific to the degree of damage of the joint.(2) In the following images there is no displacement of the clavicle and no gross abnormalities. Type I: The AC ligament is strained with no rupture of...

Given the prevalence of AC joint injuries it is important that doctors are aware of the Rockwood classification and how to accurately use it. Research shows that accuracy of AC joint injury classification could be improved, be it through additional views, or the adjunctive imaging techniques such as ultrasound, CT, MRI and 4D CT. This allows the clinician to get a better idea of the extent of the injury, which will have important ramifications for the eventual management of it. Unfortunately there are limitations in...

Himanshu Thalagala is a fourth year medical student at the University of Queensland. He has an interest in radiology and learning the application of the different imaging modalities available.

1. Mazzocca AD, Arciero RA, Bicos J. Evaluation and treatment of acromioclavicular joint injuries. The American journal of sports medicine. 2007;35(2):316-29. 2. Rockwood CA. Injuries to the acromioclavicular joint: Subluxations and dislocations about the shoulder. . Fractures in Adults. 1984:860-910. 3. Lasanianos NG, Panteli M. Acromioclavicular (AC) Joint Dislocation. In: Lasanianos GN, Kanakaris KN, Giannoudis VP, editors. Trauma and Orthopaedic Classifications: A Comprehensive Overview. London: Springer London; 2015. p. 3-6. 4. Johansen JA, Grutter PW, McFarland EG, Petersen SA. Acromioclavicular joint injuries: indications for treatment...