A skull fracture is a break in a bone surrounding the brain.

• Skull fracture can occur with or without brain damage.
• Symptoms may include pain, symptoms of brain damage, and, in certain fractures, fluid leaking from the nose or ears or bruises behind the ears or around the eyes.
• Computed tomography is used to diagnose skull fractures.
• Many skull fractures require no treatment.

Skull fractures can injure arteries and veins, which then bleed into the spaces around brain tissue. In people with a skull fracture, brain damage may be more severe than in people with a head injury but no fracture. However, a skull fracture often occurs without brain damage. Fractures, especially at the back and bottom (base) of the skull, can tear the meninges, the layers of tissue that cover the brain. Rarely, bacteria enter the skull through such fractures, causing infection and severe brain damage. Sometimes, pieces of the fractured skull bone press inward and damage the brain. These types of fractures are called depressed fractures. Depressed skull fractures may expose the brain to the environment and foreign material, leading to infection or the formation of abscesses (collections of pus) within the brain.

Symptoms

Certain symptoms suggest a fracture at the base of the skull:

• Cerebrospinal fluid—the clear fluid that flows over the surface of the brain between the meninges—may leak from the nose (rhinorrhea) or ears (otorrhea).
• Blood may collect behind the eardrum, or if the eardrum is ruptured, blood may drain from the ear.
• Bruises may develop behind the ear (Battle's sign) or around the eyes (raccoon's eyes).

Blood may collect in the sinuses, which may also be fractured.

Diagnosis and Treatment

Skull fractures are usually diagnosed in people with head injury who are undergoing computed tomography (CT). CT is better than magnetic resonance imaging (MRI) for diagnosing skull fractures.

Most people with skull fractures without brain injury are admitted to the hospital and observed. People who develop seizures require anticonvulsants. Other than fractures of the base of the skull and depressed skull fractures, most skull fractures require no specific treatment.

Fractures at the Base of the Skull: People with a fracture of the base of the skull are admitted to the hospital. Bed rest and head elevation are needed until cerebrospinal fluid stops leaking. People should avoid blowing their nose because often a sinus near the nose is also fractured. If so, blowing the nose can cause air from the nose to spread to other parts of the face or head. Most meningeal tears seal up on their own within 48 hours or at least within a week after the injury. If cerebrospinal fluid continues to leak, then doctors can sometimes drain the fluid by inserting a small needle in the lower back. If fluid continues to leak, the leak is closed surgically.

Did You Know... X-rays of the skull are rarely helpful.

Depressed Skull Fractures: In this type of fracture, one or more fragments of bone may press inward on the brain, damaging the brain. The brain may be exposed to the outside. Doctors aim to prevent infection and the formation of abscesses by removing foreign materials and dead tissue and repairing as much of the damage as possible. Doctors lift skull fragments back into position and stitch the wound closed.

Skull Fractures in Children: In infants who have a skull fracture, the membranes surrounding the brain occasionally protrude through and become trapped by the fracture, forming a fluid-filled sac called a growing fracture or leptomeningeal cyst. The sac develops over 3 to 6 weeks and may be the first evidence that the skull was fractured.

A child with a skull fracture is admitted to the hospital if

• Symptoms suggest possible brain injury.
• The child was unconscious, even briefly.
• Symptoms or CT findings suggest a fracture at the base of the skull.
• The fracture occurs in an infant.
• Child abuse is suspected.

Treatment of leptomeningeal cysts may involve observation only, since these fluid-filled sacs sometimes heal themselves. In children who develop or become at risk of developing problems such as pressure on the brain or infection, doctors surgically drain the cyst.

Last full review/revision January 2008 by Kenneth Maiese, MD