Delayed complications of ethmoid fractures are considered relatively rare. However, meningitis, recurrence of previously ceased cerebrospinal fluid rhinorrhea and delayed onset of cerebrospinal fluid rhinorrhea are possible even years after trauma. We report 10 consecutive patients with delayed complications of ethmoid fractures, whom we treated over the past 11 years. All patients had previously sustained a closed head injury and had remained anosmic. Variously after trauma (ranging from 2 months to 31 years), these patients were re-admitted because of meningitis (6 cases), recurrence of previously ceased cerebrospinal fluid rhinorrhea (3 cases), and delayed onset of cerebrospinal fluid rhinorrhea (1 case). In all cases the delayed complications were associated with relatively large defects of the ethmoid bone. These bone lesions were now evident even in those patients whose radiological assessments had been normal after trauma. All patients underwent a successful surgical repair and remained well during the follow-up. We discuss the possibility that delayed complications of ethmoid fractures are due to a mechanism like that of "growing fractures" in children.