What Is a Concussion? Symptoms, Causes, Diagnosis, and Treatment
A concussion is a mild traumatic brain injury (mTBI) that is caused by a blow to the head or chest, whiplash, or other violent shaking of the head and body. It can occur with or without the loss of consciousness and may lead to temporary cognitive problems.
Concussions are the most common form of TBI.
Most people who get a concussion will recover, but for some people symptoms can last days, weeks, or longer. The recovery period may be longer for older adults, young children, and teens. Recovery may also take longer for people with a personal or family history of migraine, ADHD, or other learning disorders.
Especially early on, symptoms of a concussion may be overlooked or mistaken for less-serious health problems. Sometimes people with a concussion do not recognize the symptoms, confuse them with something else, or don’t want to admit there's something wrong. Others may not understand what is happening to their bodies and how it is affecting their day-to-day lives.
That's why it’s especially important for everyone to know the signs of a concussion and be vigilant in looking out for them, especially when someone has experienced a blow to the head.
Symptoms of a concussion fall into four categories: physical, cognitive, emotional or mood-related, and sleep.
Typically a person will experience symptoms within minutes of the injury to the head, but sometimes concussion symptoms can take several hours or days to appear. Symptoms can also change after a few days or appear with stress.
Although rare, a person with a concussion can develop a dangerous blood clot or brain bleed that pushes the brain against the skull, which can sometimes be fatal.
Contact your doctor or local emergency department immediately if you experience any of the following danger signs after a blow, bump, or jolt to the body or head:
A headache that gets worse and does not go away, perhaps even the worst headache of your life
Weakness, numbness, or decreased coordination
Repeated vomiting or nausea
Slurred speech
If you’re caring for someone who you think might have a concussion, take them to the emergency room immediately if they:
Look very drowsy or cannot wake up
Have one pupil larger than the other
Have seizures or convulsions
Cannot recognize people or places
Are getting more confused, restless, or agitated
Are behaving unusually
Lose consciousness
Danger signs in children can include all the above, as well as refusal to nurse or eat and crying that won’t stop.
A concussion is caused by a blow, bump, or jolt to the head or chest, a violent shaking of the head or upper body (as in whiplash, for instance), or a penetrating injury, such as a gunshot wound.
The most common causes of traumatic brain injuries in the United States include falls, firearm-related injuries, motor vehicle crashes, and assault. Falls account for about half of all TBI-related hospitalizations in the United States.
Contact sports are likely the most common cause of concussions. According to the Brain Injury Research Institute, an estimated 1.6 to 3.8 million sports and recreation-related concussions occur every year in the United States.
A concussion is often diagnosed in an emergency room after a fall or accident or after an incident during a sports game. A concussion can also be diagnosed later on, when a person seeks treatment following symptoms that started after the initial blow.
Diagnosis is a several-step process that involves the following:
Interview A doctor will document the extent of any loss of consciousness or loss of memory leading up to the event, or loss of memory of the event or after the injury, as well as any other symptoms, such as headache, feeling dazed or confused, dizziness, or fatigue.
Examination The doctor will look for any neurological signs and symptoms by testing strength, sensation, reflexes, coordination, balance, vision, hearing, mental status, nerve functions, and other functions to determine the severity of the brain injury.
Brain imaging Sometimes brain imaging may be recommended for patients with symptoms of severe headaches, seizures, repeated vomiting, or symptoms that continue to worsen. A cranial computerized tomography (CT) scan can determine whether the injury is severe and has caused bleeding or swelling in the brain. Magnetic resonance imaging (MRI) can determine if the brain has undergone any changes and can help diagnose complications after a concussion. A normal CT or MRI does not rule out a concussion, though.
Observation Some patients may need to be hospitalized overnight for observation following a concussion. It may also be possible to be observed at home. A caregiver should observe the affected person closely for at least 24 hours to make sure symptoms aren’t getting worse.
In recent years, researchers have been working on more effective ways to diagnose concussions. In January 2021, the U.S. Food and Drug Administration (FDA) cleared the first rapid handheld blood test for concussions. The test requires a small blood sample from the arm, from which plasma is extracted and tested. Results are available within 15 minutes. A negative result eliminates the need for a CT scan. Abbott, the maker of the test, expects it to become available for everyday use by clinicians.
Most people who get a concussion will recover within a few days. But for some people symptoms can last for weeks or even longer.
How quickly someone improves depends on many factors, including the severity of the concussion, their age, how healthy they were before the injury, and how well they care for themselves after the concussion.
The recovery period may be longer for older adults, young children, and teens.
Most people recover completely from a concussion. The most important step in concussion recovery is getting plenty of rest, which is necessary to help the brain heal. It’s also important to avoid physically and mentally demanding activities until symptoms subside.
Medication may be prescribed to deal with headache pain, nausea, or sleep problems related to the traumatic brain injury.
Symptoms of most concussions and other mild TBIs will go away on their own within a couple of weeks. But for some people, symptoms last longer and may cause complications.
Second impact syndrome is a rare but serious potential complication that happens when a second concussion occurs before the first one has had time to completely heal. This can lead to rapid and severe brain swelling, which can turn fatal.
Research has also linked moderate to severe brain trauma with an increased risk of Alzheimer’s disease and other types of dementia. The Alzheimer’s Association has called for more research to better understand the link.
According to the most recent numbers from the CDC, approximately 2.9 million cases of traumatic brain injury were diagnosed in emergency rooms, with 75 percent of those being mild TBIs, or concussions. This is surely an underestimate, though, as many people don’t seek treatment for concussions.
Moderate and severe TBIs, but not concussions, led to 223,050 hospitalizations in 2018 and 60,611 deaths in 2019. This is equivalent to 610 TBI-related hospitalizations and 166 TBI-related deaths each day. But again, the CDC says these numbers are actually much higher, as many TBIs go untreated.
Males are two times more likely to be hospitalized and three times more likely to die from a TBI than females. Older adults age 75 or older have the highest rates of TBI-related hospitalizations and death. This age group accounts for 32 percent of all TBI-related hospitalizations and 28 percent of TBI-related deaths.
In children age 17 and younger, there were 16,480 TBI-related hospitalizations and 2,476 TBI-related deaths in 2019.
Sleep disturbance is common following a traumatic brain injury like a concussion and affects 30 to 70 percent of individuals. Common sleep problems include insomnia, sleep apnea, difficulty staying asleep, daytime sleepiness, and narcolepsy.
One study of U.S. veterans found that those who sustained mild TBIs were 49 percent more likely to develop sleep disorders for up to five years following those injuries.
Sleep disturbances can occur regardless of the severity of a brain injury. Research suggests that sleep disorders affect individuals with a concussion or mild TBI more severely. This could be because the individual is more aware of their deficits or increased social pressure to reintegrate into their daily life, since a concussion is often viewed as a less-severe form of brain injury.
It's important to talk to your doctor about any sleep problems you're experiencing with a TBI so that proper treatment can be administered. Treatment may include sleep medication, cognitive behavioral therapy, or other behavioral modifications, according to past research.
For many years, doctors treated concussions in men and women the same. But research now shows that a traumatic brain injury has different effects on the two sexes. For example, research shows that female athletes sustain more concussions than males. Females also take longer to recover and experience more severe symptoms.
A common cause of concussion is trauma during a professional or recreational sport, including but not limited to football, soccer, and hockey.
Though football seems to get the most attention when it comes to concussions, the injury is common in many other sports, especially in female sports. Concussion rates are high in ice and field hockey, lacrosse, soccer, basketball, volleyball, cheerleading, gymnastics, wrestling, baseball, and softball.
To treat concussions in sports, most post-concussion rehab protocols use exercise of graded intensity (rather than pure rest) before the person returns to play.
If you suspect that your child has had a concussion, go to the emergency room if you see any of the following signs:
Loss of consciousness
Trouble walking
Blurred vision
Slurred speech
Confusion
Severe headache, or a headache that gets worse
Call your doctor if your child complains of headache, dizziness, or memory problems after a hit on the head. The doctor will perform a physical exam and will test things like balance, coordination, and nerve function. A brain scan might also be performed to rule out internal bleeding.
Fast action can lead to a proper diagnosis and treatment to help your child recover. Since concussions are unique to each individual, your child’s doctor will prescribe treatment based on specific symptoms. If the concussion is not severe enough to warrant a trip to the hospital, your child’s doctor will provide instructions for home care.
Home care includes the following:
Physical rest until symptoms subside
Mental rest and avoidance of mentally taxing activities until symptoms subside
Eating well and avoiding caffeine
Avoiding bright lights or loud noises, which can make symptoms worse
Note that there is no evidence to support waking a child every few hours when they are sleeping to check for symptoms. Also, children can usually return to their normal activities within a few weeks. It’s important to wait until their doctor gives the go ahead to do so, and they and should stop what they are doing if symptoms return.
Headache, dizziness, blurred vision — how well do you know the signs of a concussion? In order to receive prompt treatment and prevent complications, it’s important to be aware of the ways a concussion can occur and the symptoms that may be present.
