Aerorachia.

Subcutaneous and mediastinal sometimes emphysema occurs in critically ill patients in association with soft-tissue infections, mucosal disruption, penetrating trauma or any condition that creates a pressure gradient between the intraalveolar and perivascular spaces. The aberrant air can spread along the fascia into different anatomical areas, and may reach the mediastinum and the peritoneum. In two cases we found some air inside the dorsal spinal area. This localisation has not been previously described in the literature.