Neuroradiology

Growing fracture

radiological term which describes a progressive enlargement of a linear skull fracture, that does not heal. This is due to the interposition of the meninges between the diastatic bones preventing osteoblasts from migrating across the fracture. At the same time, pulsating CSF causes progressive enlargement of the fracture and extension of the meninges extracranially. The associated meningeal anomaly is called a "leptomeningeal cyst".

On plain films, the growing fracture appears as a radiolucent linear space with distinct bony margins, which resembles a lytic calvarial lesion.

CT and MR may show the underlying CSF cyst and meningeal tear.

GS