Delayed posterior sternoclavicular joint dislocation in a young adult managed with plate fixation and cardiothoracic collaboration.

INTRODUCTION: Posterior sternoclavicular joint (SCJ) dislocations are rare, accounting for <1 % of all joint dislocations. Despite their rarity, these injuries warrant urgent recognition due to the SCJ's proximity to mediastinal structures, including the trachea, esophagus, and great vessels. While not always surgical emergencies, delayed or unstable cases can result in life-threatening complications if not managed in an appropriately equipped hospital setting.

CASE PRESENTATION: A 28-year-old male presented two weeks after sustaining a right SCJ injury while sliding during a softball game. He reported persistent pain, difficulty breathing, and limited shoulder function. Initial radiographs were unremarkable; however, CT imaging revealed a posterior dislocation of the medial clavicle. Given the delayed presentation and potential mediastinal involvement, the patient underwent open reduction and internal fixation (ORIF) with cardiothoracic surgical assistance. Fixation was achieved using unicortical screws in the sternum and bicortical screws in the clavicle. He recovered without complications and returned to full activity CONCLUSION: : Posterior SCJ dislocations are challenging to diagnose on radiographs and often require CT for accurate assessment. Although closed reduction is an option in acute cases, delayed presentations typically necessitate surgical stabilization. Plate fixation offers reliable alignment and secure fixation. This case underscores the importance of timely diagnosis, hospital-based care, and multidisciplinary surgical planning when managing posterior SCJ dislocations.