A Broken Skull

A skull fracture is a broken bone of the skull, not a per se, injury to the brain. The skull is essentially the brain's helmet, but it also is part of several structures that work together like an egg carton. Like an egg, the brain is far more vulnerable to injury than other parts of the body, and needs an elaborate structure to keep it safe from routine contact. The skull is just the first line of defense, with the cerebral spinal fluid working in conjunction with the dura and the arachnoid mechanisms to suspend the brain inside the skull in such a way that even less routine blows will leave the brain undamaged.

In terms of evolutionary engineering, the skull also does work to some degree like a modern bicycle helmet, designed to give itself up to save the brain from the next layer of force. Thus, the energy that it takes to crack the skull, will absorb some of the force that would otherwise injure the brain. This design of a helmet/egg carton for the brain is actually an exquisite structure to protect the brain from pre-industrial revolutionary forces. The skull does a great job of protecting humans from rocks thrown at them, animal bites, falls onto hard objects. Unfortunately, in too many modern accidents that involve high speed and rapid deceleration, the forces exceed what evolution has had time to adapt to. Human evolution takes millennium; man has only gone over 60 mph for a hundred years.

While it is possible to have a fractured skull and very little brain damage, the probability of serious injury does go up with a skull factor. In a high speed accident, while the skull still does protect the brain from external impact, the internal impact of the brain against the inside of the skull, can be extremely dangerous. And the more massive the skull injury, the more likely it can come with catastrophic injury to the brain. It takes considerable force to break any bone, particularly the skull. Depending on the vector and the degree of that force, it may be sufficient to damage the brain as well. The risk of an associated hematoma (bruise) can be increased as much as 400 fold after a skull fracture.

In a high speed accident, while the skull still does protect the brain from external impact, the internal impact of the brain against the inside of the skull, can be extremely dangerous.

Skull fractures are the easiest of traumatic head injuries to be imaged, as they not only show up clearly on CT, they are also likely to be spotted on X-ray. One area where they are sometimes missed are at the base of the skull - where basilar skull fracture may still be more easily diagnosed by symmetrical black eyes, called "Raccoon Sign", than on CT.

The Role of Dura In Understanding Severe TBI Pathology

When the skull breaks, the energy is likely to be transferred by direct contact to the adjacent areas of brain tissue. The brain is encased in the “dura”, and arachnoid membranes, which are almost like a tight fitting bag. It is the dura which first makes contact with the skull in an injury event. 

Gordon S. Johnson, Jr., the author of this page is a lawyer, not a doctor, who practices law with the Brain Injury Law Group, S.C. Click here for more on the firm

Contact Attorney Gordon Johnson: 1-800-992-9447

This site is brought to you by the advocates of the Brain Injury Law Group, a community of plaintiff's trial lawyers across the United States united by a common interest in serving the rights of persons with traumatic brain injuries and a common commitment to fully understanding the anatomic, medical and psychological aspects of TBI.

Contact Attorney Gordon Johnson: 1-800-992-9447

This site is brought to you by the advocates of the Brain Injury Law Group, a community of plaintiff's trial lawyers across the United States united by a common interest in serving the rights of persons with traumatic brain injuries and a common commitment to fully understanding the anatomic, medical and psychological aspects of TBI.