Magnetic resonance imaging imaging in the diagnosis of sternoclavicular joint injuries.

BACKGROUND

Currently, computed tomograhy (CT) scans are the investigation of choice for any sternoclavicular joint (SCJ) injury. However, apart from a true anterior or posterior dislocation, a CT scan has a minimal ability to assess damage to the stabilizing soft-tissue structures once the joint has been reduced.We have developed an SCJ magnetic resonance imaging (MRI)/MRI arthrogram imaging protocol for patients with SCJ injuries. The purpose of this study was to correlate SCJ soft-tissue injury configurations demonstrated on MRI/MRI arthrograms with clinical findings and to assess whether these results were able to guide further treatment.

METHODS

We developed a nonorthogonal (NO) MRI (acute injury) and NO-MRI arthrogram (chronic injury) protocol to image SCJ injuries. We reviewed our database for all patients who had undergone NO-MRI imaging to investigate an SCJ injury.We divided the patients into 5 groups based on their pre-scan clinical diagnosis (group 1: traumatic SCJ instability, group 2: atraumatic SCJ instability, group 3: SCJ injury without instability, group 4: adolescent posterior SCJ injuries, group 5: previous SCJ instability surgery). Each patient was assessed as to whether the scan demonstrated relevant pathology or not, their subsequent treatment, and whether any further investigations were required to decide this.

RESULTS

Over the study period, 246 NO-MRI scans were undertaken in total. Group 1: 87 of 119 scans showed evidence of some form of acute or chronic anterior and/or posterior ligamentous injury; 78 patients underwent surgery. Group 2: 36 of 43 patients showed no capsular damage; whereas 7 patients had a capsular tear reclassifying their diagnosis as traumatic instability. Group 3: 29 out of 55 patients demonstrated evidence of either a traumatic intra-articular disk tear or a vertical sternal fracture; 26 underwent surgery. Group 4: 6 of the 27 patients demonstrated either an off-ended medial physeal injury or a true posterior SCJ dislocation; all underwent surgery. Group 5: 15 out of 19 patients demonstrated varying pathologies; 12 underwent surgery.

CONCLUSION

An NO-MRI scan and an NO-MRI arthrogram provide a good assessment of the structural soft-tissue injuries associated with acute and chronic SCJ injuries and provide a reliable guide to further clinical management.