Sacral meningocele and rectal fistula associated with pneumorrhachis and pneumocephalus. A case report and literature review.

Pneumorrhachis (PR), the presence of air in the spinal canal, is a rare but suggestive radiographic finding, associated to different aetiologies and possible pathways of air entry into the spinal canal. It can be divided into primary and secondary PR, descriptively classified into extra- or intradural PR and aetiologically subsumed into iatrogenic, traumatic and non traumatic PR. Pneumoencephalus (PE), lack of air in the skull, is the equivalent intracranial phenomenon, associated mostly with traumatic or iatrogenic aetiology. Non traumatic PR and PE, especially when concurrent, are an uncommon radiological finding.