Open Head Injuries
In an open head injury, something, often a foreign object, breaks through the skull and enters the brain or breaks off pieces of the skull into the brain. The penetration can cause severe nerve damage, lacerations, bleeding and hematomas. These brain injuries are typically caused by a direct blow to the head as a result of high velocity impact such as a car, motorcycle or bicycle accident.
Open head injuries are sometimes called penetrating head injuries because they occur with penetration, but this is a slightly inaccurate term. Open head injuries encompass penetrating, perforating and tangential injuries. Penetrating injuries are actually a sub category of open head injuries in which an object that enters the skull remains in the brain. Perforating injuries, in contrast, occur when an object enters and exits the skull, leaving both entry and exit wounds. Tangential injuries occur when an object ricochets or bounces off the skull, driving bone fragments into the brain.
Open head injuries are tremendously dangerous, and thankfully, tremendously rare discounting gunshot wounds. The risk for infection is extremely high because the brain is exposed to outside bacteria, usually for the first time ever. With penetrating and perforating wounds, the injured person typically looses a lot of blood and faces permanent damage to the brain.
Closed Head Injuries
Closed head injuries occur when the head suffers trauma without any penetration of the skull. Despite the skull remaining intact, the brain can still suffer severe damage.
Direct blows to the head are common causes of closed head injuries, but they are not the only mechanism for harm. Brains that are violently shaken in a motor vehicle accident can suffer serious brain damage without any direct impact to the head. In fact, in those cases the skull is what damages the brain, not any external object. See coup-contrecoup injuries for more on this.
Closed head injuries account for 75% of all traumatic brain injuries. The severity is often hard to identify without specialized scans, such as CT or MRI.
If you or a loved one has suffered a serious blow to the head in an accident, see a doctor immediately, and then call us. We can help you understand what to expect in dealing with a severe brain injury.