Posterior Sternoclavicular Joint Dislocation in a Pediatric Wrestler: Delayed Diagnosis After Initially Benign Radiographs

Posterior sternoclavicular joint (SC) dislocation is a rare but potentially life-threatening injury in pediatric athletes due to its proximity to mediastinal structures and frequent delay in diagnosis. We present a previously healthy 13-year-old male wrestler who developed persistent right SC pain and swelling after a forceful shoulder impact during a match, initially diagnosed as an acromioclavicular (AC) joint injury based on plain radiographs. Despite conservative management, continued symptoms prompted further assessment with computed tomography, which revealed a posterior SC joint dislocation. The patient underwent successful open reduction and stabilization without complications and progressed appropriately postoperatively. This case highlights the importance of maintaining a high index of suspicion and obtaining timely advanced imaging in young athletes with persistent SC pain following high-energy trauma to prevent serious complications and ensure safe return to sport. Though not seen in this patient, posterior SC dislocation can lead to cardiovascular, neurovascular, or airway compromise. Despite the initially reassuring shoulder X-ray, the mechanism of injury and severity of intractable pain ultimately led to the final diagnosis.