The lateral cervical spine x-ray shows pre-vertebral air. The C-spine AP view shows streaks of air in the superior mediastinum. There is no cervical spine fracture.

A chest x-ray indicated pneumomediastinum.

This patient went on to have CT scan of his face and chest. There was no chest injury, but he had a complex mid-face fracture involving both the maxillary and frontal sinuses. The resulting surgical emphysema had tracked into the retropharyngeal space, thereby resulting in pneumomediastinum due to distal tracking of the air.

Pneumomediastinum is normally due to an injury to the aero-digestive tract. Extra-thoracic causes include pneumoperitoneum, sinus fractures, and a traumatic dental extraction.