What Is It?
Trauma to the head can cause a range of medical problems, from mild to severe. Each year, childhood head injuries result in more than 500,000 emergency room visits in the United States, with more than 95,000 hospitalizations. Although 90% of all childhood head injuries are minor, about 7,000 children die each year from head trauma, and an additional 29,000 develop permanent disabilities. The most common causes of childhood head injuries in the United States are motor vehicle accidents, falls, assaults, bicycle accidents and trauma related to sports. In infants younger than 1 year old, more than 95% of serious head injuries are related to child abuse.
Children often bump their heads accidentally, resulting in minor bumps, bruises, or cuts in the scalp, but no damage to the brain inside. Sometimes, more serious injuries happen.
When injuries to the head cause a change in the ability to think clearly, it is called a concussion. Concussions are graded on a scale of I to III, depending on the severity of the symptoms. A grade I concussion is the mildest type, with confusion lasting 15 minutes or less, while a grade III concussion is the most severe, with confusion, loss of memory (amnesia) and loss of consciousness (passing out) for a few seconds up to a few minutes. In most cases of concussion, X-rays or brain scans do not show any damage. Concussions usually do not cause long-term brain damage, unless the child suffers repeated concussions (for example, during high-risk activities such as boxing or football).
Childhood head trauma is rarely more serious than a concussion. However, when it is severe, the injury usually is from a direct blow to the skull. Sometimes, the injury can be caused indirectly, such as when blood vessels stretch and tear, the brain "bounces" against the inside wall of the skull, or the brain swells as a result of chemical changes.
The most serious types of brain injury include:
Skull fracture - A skull fracture is a crack or break in one of the skull's bones. In most cases, a skull fracture causes only a bruise on the surface of the brain. If the skull is dented inward (a depressed skull fracture), pieces of the broken bone are pressing down against the surface of the brain. This may need special surgery to fix.
Epidural hematoma - This is one of the most serious types of bleeding that can occur inside the head as a result of a skull fracture. It happens when a sharp fragment of bone cuts through one of the major blood vessels in the skull. As the injured vessel bleeds, a collection of blood called a hematoma forms in the space between the skull and the outermost membrane (dura) covering the brain. The blood vessel that ruptures is usually an artery, and the hematoma expands rapidly and presses on the brain. This can cause severe injury and even death. Epidural hematomas are especially common after significant injuries to the temple, such being hit by a baseball or baseball bat.
Subdural hematoma - This is a collection of blood between the coverings of the brain and its surface. It occurs when a head injury tears any of the large veins that carry blood away from the brain's surface. Subdural hematomas tend to get larger slowly, sometimes over days or weeks, with symptoms gradually worsening. This type of bleeding leads to serious brain injury and even death if not diagnosed and treated promptly.
Intraparenchymal hemorrhages and contusions (bleeding and bruising of the brain) - These injuries involve the brain itself. Both types of injury are caused by either a direct blow to the head or indirectly when the force of an injury to one side of the skull causes the brain to bounce against the other side. This causes an area of damage on the side of the brain opposite from the blow to the head.