Medicine
Skull Fractures
Quick fact
Skull fractures are present in about 4% of all patients with head injuries, and basilar skull fractures may be identified by raccoon eyes (periorbital ecchymosis) or Battle's sign (bruising behind the ear).
Why this is interesting
A hard fall can crack your skull, but not all skull fractures are alike. Why do some heal on their own while others require immediate surgery?
Read the full explanation
Understanding Skull Fractures
Think of the skull as a protective helmet for the brain. A skull fracture is like a crack in that helmet. But unlike a bike helmet, the skull is made of bone with different thicknesses and strengths. A fracture can be linear (a simple crack), depressed (a piece is pushed inward), or basilar (at the base of the skull). The type of fracture tells doctors how much force was involved and what structures—like blood vessels or the brain itself—might be at risk. For instance, a depressed fracture can compress brain tissue, while a linear fracture over a blood vessel may lead to an epidural hematoma.
A deeper explanation
The skull is composed of several fused bones: the frontal, parietal, temporal, occipital, sphenoid, and ethmoid. When a force exceeds the bone's tensile strength, a fracture occurs. The mechanism involves energy transmission: a high-energy impact (e.g., from a car accident) often causes multiple or complex fractures, while a low-energy fall may produce a simple linear crack. The significance of a fracture extends beyond the bone itself. For example, a basilar fracture can tear the dura mater (the brain's outer covering), allowing cerebrospinal fluid to leak from the nose or ear, increasing infection risk. Depressed fractures may require surgical elevation to relieve pressure on the brain. Understanding these patterns helps clinicians anticipate complications like meningitis, intracranial bleeding, or seizures. Moreover, the presence of a skull fracture alone does not indicate brain injury severity; it is the associated damage to underlying structures that truly matters.