A concussion is a type of brain injury that’s common in all types of accidents, from car accidents to falls. Unfortunately, many concussions are not apparent at first or may only cause very subtle symptoms. This can lead injury victims to presume they are fine and do not need treatment.
How hard do you have to hit your head to get a concussion? The truth is you do not even need to hit your head to suffer a concussion. Brain injuries can occur when the brain strikes the inside of the skull without any external trauma.
We’ll explore common misconceptions about how you can get a concussion and why you should seek treatment as soon as possible if you are injured or have concussion symptoms – even if you did not hit your head or lose consciousness.
One of the most dangerous myths about concussions is that a concussion can only happen after a blow to the head. The truth is you can get a concussion from a car accident without hitting your head, or from any accident that causes sudden, violent movement of the head or rapid deceleration.
Concussions are trauma to the brain that happen when the brain strikes the inside of the skull. This can happen when your head strikes your steering wheel, the ground, or a hard surface. It can also happen due to rapid deceleration or a violent twisting or shaking motion.
There are many well-known examples of concussions and other forms of brain damage that do not involve a blow to the head. You may be familiar with examples such as:
To imagine how easy it is to suffer a concussion without hitting your head, imagine your brain as a water-filled balloon floating in higher density saltwater in a jar. Shaking the jar gently or moving it does not cause the balloon to touch the sides of the jar. If the jar is struck hard enough, or you move the jar very fast and stop suddenly, the balloon will be struck against the jar.
When a vehicle stops suddenly in a crash, your body continues to move. If you are wearing a seatbelt, your body is forced in the opposite direction. However, the brain, which floats in a cushioning fluid, has nothing to stop its forward acceleration. It strikes the inside of the skull and, if the force is great enough, bounces and strikes the opposite side of the skull. This is known as a contrecoup-coup injury.
Concussions occur in much the same way when the brain hits the inside of the skull or the force of an accident cause more widespread damage to the brain.
This is why a brain injury from a car accident can happen at even low speeds.
Another common misconception is a concussion requires losing consciousness. While a loss of consciousness is a sign of a concussion or more serious brain injury, passing out is actually uncommon. A study by the University of Pittsburgh Medical Center (UPMC) found less than 10% of concussions involved loss of consciousness.
Losing consciousness after an accident can indicate a more serious brain injury, but you should always seek medical attention even without loss of consciousness, headache, or other signs of a concussion.
A concussion happens when the force of impact or sudden deceleration causes the brain to move forcefully against the opposite side of the skull. There is no threshold of force that will result in a concussion for everyone as every person and brain is different.
G-force is a measure of acceleration against the gravitational pull of the earth. For years, researchers believed that concussions mostly happen at 90-100 g-force, but numerous studies are finding concussions happen frequently at 60g. 90-100 g-force is equivalent to the skull smashing into a wall at 20 mph. Far less forceful blows can cause a concussion.
The National Football League commissioned research using crash test dummies that calculated blows above 85g would most likely cause a concussion while anything below this would not.
However, the University of North Carolina’s Center for the Study of Retired Athletes found otherwise. Of the 13 concussions the researchers recorded over five seasons, six resulted from hits at or below the 85g threshold and seven ranged from 100g to 169g. Using helmets with sensors that recorded over 104,000 impacts, many hits over 98g did not cause concussions and just 0.33% of all blows over 80g caused concussions. Many hits at 60-63g did cause concussions, however.
It’s also important to remember that low-speed car accidents at just 5-15 mph can also cause concussions and other serious brain injuries. Low-speed crashes do not result in serious damage to the vehicle. Energy that doesn’t go into damaging the car is transferred into kinetic energy or acceleration. This is the cause of brain injuries. That means a lower speed crash with virtually no property damage has a higher chance of causing injury than a higher speed crash that causes structural damage to the car.
According to the Spine Research Institute of San Diego, a 5 mph car crash usually produces 10-12g of acceleration of the passenger’s head. The head has a higher peak acceleration than the vehicle’s peak acceleration. Even low-speed crashes can be sufficient to cause a concussion or a coup-contrecoup injury because they cause a proportionally greater energy transfer.
In fact, research even shows an inverse relationship between the potential for injury and property damage.
There is no link between the severity of damage to a vehicle in a crash and the severity of injuries.
Because many people believe that a concussion requires a blow to the head or losing consciousness, it’s common for accident victims to suffer a concussion without realizing it. This is especially true because mild concussions may have no symptoms at first or the symptoms may be disregarded.
After a fall, car crash, or sports injury, it’s possible for concussion symptoms to be masked by shock. They can even take days or weeks to develop. Some victims develop confusion after an injury that makes them unable to recognize that they may have suffered a brain injury.
A growing body of research even indicates that “subconcussive” damage can have a cumulative effect. A subconcussion is a possible brain injury that does not rise to the level of a concussion and generally has no symptoms.
The most common early symptoms of a concussion include dizziness, memory loss, headache, and confusion. Victims may mistakenly attribute these symptoms to the shock and pain of the accident itself. Mood and sleep changes and sensitivity to light and sound are more likely to be delayed by days or weeks.
A concussion is a brain injury caused by a blow to the head or a jolt or sudden deceleration that causes the brain to strike the inside of the skull, axons to shear off, or more widespread damage to the brain.
Most people are familiar with common causes of concussions that involve blows to the head including contact sports like football and car accidents. It’s important to understand the many ways in which you can get a concussion without hitting your head including:
After an accident, it’s a good idea to seek medical care right away. You should also watch for any symptoms that may indicate a brain injury, even if you did not get your head. These symptoms may not appear for days. A concussion may not be detected during initial medical treatment, but you should return to your doctor if you later develop symptoms.
Concussion symptoms without hitting head may include:
A headache is one of the most common symptoms of a concussion and a symptom that makes many injury victims first suspect they may have suffered a brain injury. However, a concussion without headache is possible with or without hitting your head.
Have you or someone you love suffered a concussion in a car accident, fall, or other accident? After seeking medical attention, your next step should be contacting an experienced San Diego brain injury lawyer to discuss your options.
Sadly, insurance companies often fight back against concussion injury cases, especially those involving low-speed collisions. They may claim you could not have been seriously hurt without significant damage to your vehicle or downplay the severity of your injury.
Berman & Riedel, LLP is prepared to fight on your behalf for the compensation you deserve to get the treatment you need and preserve your quality of life. We have secured life-changing traumatic brain injury settlements for our clients and we will work to do the same for you.
Our personal injury law firm is based in San Diego, but we represent injury victims throughout California. Contact our law office today for a free consultation with a California brain injury attorney to discuss the details of your case.





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