Jason Bourne and the biomechanics of auto injuries

I was watching one of the Jason Bourne films with my kids the other day. There is a scene where Bourne’s car is pushed off a bridge and falls 100 feet, but since he wraps the seatbelt around his arms and shoulders and splays his body across the seat, he exits with only a slight limp.

Action movies are fast-paced and great fun, but in reality, Jason would be a goner. . . and we know this because of the study of biomechanics (biology and mechanics of Injuries). Extensive studies have been done on car accidents to see how people are hurt, and how to make vehicles safer in the future.  Below are some of the findings:

The rear-end collision (or fender bender)

Table of Contents

• The rear-end collision (or fender bender)
• Frontal crashes
• Side crashes
• Multiple impacts
• Other Issues

These accidents typically cause back and neck injuries that are soft tissue in nature (bulging or herniated discs). Why? Because upon impact, both you and your car are jerked forward suddenly. In response, your body is snapped back quickly, usually by your seatbelt, and your spine and skull crash violently against the seat behind you. As a result, your neck and back are flexing and extending, and your joints are colliding with one another. That your body suddenly becomes aware of an impact and tenses up, doesn’t help. You go to the hospital that does x-rays and says you have no fractures.

Shortly after the accident, you have a headache or sore neck or back. Perhaps a couple of days later your back is in spasm and you can’t get comfortable in bed. Or you have shooting pain down your arm or leg. That is a disc injury, which is best confirmed by having an MRI. A small part of one or several of your discs (the soft pad positioned in between each of the vertebrae of the spine, which act as shock absorbers, and allows movement in the spine) has now shifted out of position and is touching spinal nerves, often producing severe pain.

For the driver, who senses the accident is coming and tenses up, he may suffer a shoulder tear as he tightly grips the steering wheel and locks the arms. For passengers, they may suffer a similar injury if they brace their hands on the dashboard. These “bracing for impact” injuries are not just from rear-end collisions – they apply to all accidents since protecting oneself is human nature.

Frontal crashes

In frontal impacts, the occupant is moving forward at the same speed as the vehicle just before the crash. So, let’s say you are traveling at 40 mph. When your car stops, your body is still traveling at 40 mph (the process is called inertia). An airbag, if it opens, deploys at a fast speed to counterbalance your body moving forward – that’s great, except if you are moving forward at 40 mph and the airbag is opening at 40 mph, then you just got hit with a really hard balloon traveling 80 mph (still better than hitting a window).

Depending on your body position, the airbag might hit you in the face, causing burns or breaking your nose. Perhaps it strikes your hand, which has gone up to protect your face, and that might break your wrist. The seatbelt also locks into position, grabbing your torso, and this may lead to rib fractures and organ damage from broken ribs piercing internal areas. The driver may also hit the steering wheel, which could damage a chest or face, or abdomen, depending on the driver’s height.

A head-on collision can also lead to the development of ankle, tibial (shin bone), femur (thigh bone), or pelvic fractures. This is because when force is applied to the front of the car, that end of the car could collapse inward, transmitting the force into the foot of the driver (who has pushed down with his right foot to slam on the brakes). In contrast, the passenger may slam their knees into the seatback or dashboard and fracture a patella (knee cap).

Side crashes

These impacts are a little more unique because of where the other vehicle strikes your car. There is less than a foot of protection between the outer portion of a car door and a person’s body, and therefore a lot less car to absorb the crash and crush energy that you are protected from with a hit from the rear or front.

Depending on the speed of the other car, it may be like getting hit with a cannonball. These impacts, even with airbag deployment, often result in serious head, shoulder, extremity, torso, and pelvic injuries from door intrusion or direct impact. Instead of moving back and forth from a frontal or rear collision, here your head and body swing left and right. So, you may strike the window or your body may twist at an unnatural angle and suffer serious trauma. There are more traumatic brain injuries in these types of cases, as the brain sloshes around inside the skull while the car spins around, or the head breaks a side window.

Multiple impacts

These are also unique. When an initial car crash happens, it does two things. It throws your body into an unnatural position and it probably opens the airbags. Now comes impact number two and all bets are off. Your body can suffer from a variety of injuries in these collisions. Worse yet, your airbag doesn’t deploy in impact one, and now your head is too close to the airbag port as it deploys, causing serious neck injuries.

Other Issues

As my mother used to say, everyone is different. I just presented “Accident and Impact 101.” Clearly, occupant age, size, weight, and physical state of health will affect injury risk and severity. So, if you are 6’9”, your injuries will be worse and probably different due to your size. If you are laying down in the back seat without a seat belt and with a leg out the window, I didn’t account for that. If the driver is wearing high-heeled shoes, she should expect ankle and foot injuries. Likewise, if an SUV strikes a Mini Cooper or the accident happens at 80 mph instead of 20 mph, circumstances change.

Perhaps you read this article and your reaction is that I’m a “Debbie Downer” or I made this stuff sound terrifying. Well, I wanted to – because it is terrifying. As an injury lawyer, I see the aftermath of these accidents daily. The problem is that young kids watch Jason Bourne crash head-on into a draw bridge and 30 seconds later, he’s drop-kicking five assassins. Again, fun, but in real life, Mr. Bourne’s leg would still be somewhere in the car and the next movie would be called “The Bourne Funeral” and probably presented as a short film.

So, what should you take from this? Drive safely, wear your seatbelt, and if your car manufacturer sends you a notice about a defective airbag on your car, get it fixed ASAP.