What you need to know about children’s head injuries.

Did you know that 3.8 million people in America report suffering from a concussion each year? Many of those injured are children. According to the Centers for Disease Control, 135,000 kids ages 5 to 18 are treated annually in U.S. hospitals for concussions sustained from sports and recreational activities, and nobody knows how many cases go unreported.

With the number of concussions being treated rising each year, minors and their parents must understand the facts. All too often, conventional wisdom is way off the mark, and that misunderstanding can be detrimental to your child’s health.

Myth #1: Helmets prevent concussions. This belief can be extremely dangerous to anyone who believes that as long as you wear a helmet, you’ll be fine. “Helmets are great at preventing skull fractures and slowing the acceleration and deceleration of the brain that can sometimes cause a vessel to rupture,” says Kevin Guskiewicz, a neuroscientist at the University of North Carolina. “However, any quick movement of the head causes the brain to move. Helmets cannot manage that energy inside the skull and therefore cannot totally prevent the acceleration and deceleration that cause concussions. So, they really are not designed to prevent concussions, but are certainly helpful in preventing more serious and catastrophic head injuries.” Still, helmets are necessary for sports like football, biking, snowboarding, skiing, rollerblading and skateboarding. Whereas a child might suffer a concussion from an accident while wearing a helmet, the damage would be considerably worse or even fatal if the child is not wearing a helmet.

Myth #2: The effects of a concussion don’t last more than a week or two. “The effects can vary widely depending on the person, the nature of the injury and a number of other factors— some known and some unknown— that result in a longer recovery time,” according to neuropsychologist Gerard Gioia, the chief of pediatric neuropsychology at Children’s National Medical Center in Washington. “Some children and adolescents do recover within two weeks, but many do not. And the average length of time is not particularly relevant because every injury has its own recovery period.” Many kids find that for up to three months after suffering a concussion, their attention span and memory are not nearly as sharp as before their accident. Headaches and sometimes nausea also occur more frequently for a period of time following a concussion.

Myth #3: Concussion symptoms show immediately. On the contrary, only about 10 percent of concussions lead to loss of consciousness. And some kids won’t notice the symptoms until a few hours after the accident. When symptoms do appear, they may include nausea, dizziness, headache, vomiting, vertigo, confusion, problems with balance, sensitivity to light and noise, irritability and amnesia. Studies have shown that 40 percent of football players who experience a concussion are back on the field before their brains are healed. “Not all concussions produce symptoms or symptoms may appear to subside after a certain period of time, such as 30 minutes, only to appear or reappear later with increasing cognitive or physical demands,” Goia says. He adds that studies have revealed that symptoms appearing later on, including more than several hours afterward, are “not observed on the sidelines in 25 to 30 percent of athletes. This is the main reason why ‘When in doubt, sit them out’ is the prevailing view. Even though the child may look fine 10 to 20 minutes after a blow to the head, one cannot predict that all symptoms have dissipated and are gone for good. We must be conservative because of the possibility of later appearing symptoms.”

Myth #4: The only way to get a concussion is to suffer a blow to the head. According to Guskiewicz: “Concussion simply refers to a violent shaking of the brain inside the skull. So, while most concussions involve a direct impact to the head, you can sustain a concussion from an impact to other parts of the body such as the back or chest that cause a rapid acceleration and deceleration of the head. A quick, whiplash-like movement of the head typically causes a rebound effect of the brain inside the skull and can easily bruise or stretch brain tissue. Fortunately, the neuronal disruption is usually temporary.”

Myth #5: The younger you are, the faster you’ll heal. Kids might delight in risky sports, recreational activities and stunts, but neurologically speaking they are the last people who should engage in them. “The immature brain is still developing,” says Julian Bailes, a neurologist at West Virginia University and the medical director for the Pop Warner Youth Football program. “That makes it susceptible to damage and more likely to suffer repetitive injury.” Following this train of thought, believing themselves resilient only puts children in more danger.