Michael G Muhonen, John G Piper, Arnold H Menezes

Growing skull fractures are poorly understood complications of pediatric skull fractures. A retrospective review of skull fractures at our institution from 1980-1993 revealed 10 patients with growing skull fractures. The age at injury ranged from 1-144 months, with 9 of 10 patients being under one year of age. The etiology of these fractures included falls, motor vehicle accidents, and child abuse. On average, growth of the fracture was diagnosed 14 months after the initial injury. Six patients have had magnetic resonance imaging (MRI) with one demonstrating leptomeningeal cyst herniation, two having brain herniation, and three having both brain parenchyma and leptomeningeal cyst herniation. All patients had malacic cortex underlying the fracture, but there was no evidence of intracranial hypertension. Nine patients have undergone craniotomy with excision of granulation tissue and gliotic brain, dural repair, and cranioplasty using surrounding normal skull. There were no surgical complications or recurrences. Brain/leptomeningeal cyst herniation through a dural rent, without MRI evidence of increased intracranial pressure, implicates physiologic growth and brain cerebrospinal fluid (CSF) pulsations as the cause of fracture enlargement.