Basilar skull fracture
| Basilar skull fracture | |
|---|---|
| Classification and external resources | |
 Diagram showing bones that may be involved in a basilar skull fracture | |
| ICD-10 | S02.1 |
| ICD-9 | 801.1 |
| eMedicine | med/2894 |
A basilar skull fracture (or basal skull fracture) is a fracture of the base of the skull, typically involving the temporal bone, occipital bone, sphenoid bone, and/or ethmoid bone.
This type of fracture is rare, occurring as the only fracture in just 4% of severe head injury patients.[1][2]
Such fractures can cause tears in the membranes surrounding the brain, or meninges, with resultant leakage of the cerebrospinal fluid (CSF). The leaking fluid may accumulate in the middle ear space, and dribble out through a perforated eardrum (CSF otorrhea) or into the nasopharynx via the eustachian tube, causing a salty taste. CSF may also drip from the nose (CSF rhinorrhea) in fractures of the anterior skull base, yielding a halo sign. These signs are pathognomonic for basilar skull fracture.[3]
Contents |
Anatomy
Basilar skull fractures include breaks in the posterior skull base or anterior skull base. The former involve the occipital bone, temporal bone, and portions of the sphenoid bone; the latter, superior portions of the sphenoid and ethmoid bones.
Bones may be broken around the foramen magnum, the hole in the base of the skull through which the spinal cord exits and becomes the brain stem, creating the risk that blood vessels and nerves exiting the hole may be damaged.[4]
Due to the proximity of the cranial nerves, injury to those nerves may occur.[3] This can cause palsy of the facial nerve or oculomotor nerve or hearing loss due to damage of cranial nerve VIII.[3]
Clinical manifestations
- Battle's sign - is ecchymosis of the mastoid process of the temporal bone.
- Raccoon eyes - is periorbital ecchymosis i.e. "black eyes"
- Cerebrospinal fluid rhinorrhea
- Cranial nerve palsy
- Bleeding from the nose and ears
- Hemotympanum
- In 1 to 10% of patients, ocular nerve entrapment occurs:[3] the ocular nerve is pressed by the broken skull bones, causing irregularities in vision.
- Serious cases usually result in death
Prognosis
Non-displaced fractures usually heal without intervention. Patients with basilar skull fractures are especially likely to get meningitis.[5]
Vascular Complications of Temporal Bone Fractures
Acute injury to the internal carotid artery (carotid dissection, occlusion, pseudoaneurysm formation) may be asymptomatic or result in life-threatening hemorrhage. They are almost exclusively observed when the carotid canal is fractured, although only a minority of carotid canal fractures result in vascular injury. Involvement of the petrous segment of the carotid canal is associated with a relatively high incidence of carotid injury.[6]
Association With Auto Racing
Basilar skull fracture is a common cause of death in auto racing accidents:
- Formula One driver Roland Ratzenberger in the 1994 San Marino Formula One Grand Prix
- Indianapolis 500 drivers Bill Vukovich, Tony Bettenhausen and Floyd Roberts.
- NASCAR drivers Dale Earnhardt Sr., Adam Petty, Tony Roper, Kenny Irwin, Jr., Neil Bonnett, John Nemechek, J. D. McDuffie, Richie Evans, and Clifford Allison. Stanley Smith also suffered the injury, but recovered.
- CART drivers Jovy Marcelo, Greg Moore and Gonzalo Rodriguez
- ARCA driver Blaise Alexander
To prevent this injury, all major motor sports sanctioning bodies now mandate the use of head and neck restraints, such as the HANS device.
See also
References
- ^ Graham DI and Gennareli TA. Chapter 5, "Pathology of Brain Damage After Head Injury" Cooper P and Golfinos G. 2000. Head Injury, 4th Ed. Morgan Hill, New York.
- ^ Orlando Regional Healthcare, Education and Development. 2004. "Overview of Adult Traumatic Brain Injuries." Retrieved on January 16, 2008.
- ^ a b c d Singh J and Stock A. 2006. "Head Trauma." Emedicine.com. Retrieved on January 26, 2007.
- ^ Brain Injury Association of America (BIAUSA). "Types of Brain Injury." Retrieved on January 26, 2007.
- ^ Dagi TF, Meyer FB, and Poletti CA. 1983. The incidence and prevention of meningitis after basilar skull fracture. American Journal of Emergency Medicine. Volume 1, Issue 3, Pages 295-298. PMID 6680635. Retrieved on March 16, 2007.
- ^ Resnick DK, Subach BR, Marion DW. The Significance of Carotid Canal Involvement in Basilar Cranial Fracture. Neurosurgery. 1997 40(6):1177-1181.ISSN: 0148-396X UI: 9179890
External links
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