Cervical surgical emphysema: rare presentation of a sigmoid colon retroperitoneal perforation with abscess rupture through the lumbar triangle of Petit.

A retroperitoneal sigmoid colon perforation presenting with cervical surgical emphysema secondary to abscess rupture through the lumbar triangle of Petit into the posterior paraspinal muscle compartment has not been previously described. We report a case where previously ingested barium clearly demonstrates this unusual pathway.