Whiplash

[Music] [Music] There is one of these behind the wheel of every moving [Music] automobile, even your car. Both you and your car have a framework. But whereas one is expendable, the other is not [Music] Wherever you drive, there's always the danger of the most common traffic mishap, the rear end collision and the subsequent possibility of whiplash. [Music] Even at low speeds, your neck or back can be injured. Dr. Seo Bectal, chief of the division of orthopedic surgery at UCLA's medical center, will point out what happens in a rear-end collision when your body is shoved forward and your head is not. There are 26 bones in your spine. A sudden stretching action causes high compression and sheer loadings with possible concussion and permanent disability. The top of a seatback acts as a fulcrum with a normal seatback height of 22 in. The force loads from impact are divided over seven vertebrae in the neck. With a seat back of 25 in the fulcrum point is higher and the loading is born principally by three vertebrae. Thus it appears that a medium height seat back could be worse than a low one. With a rigid 28 in seat back no vertebrae are exposed to strain. [Music] According to Dr. Beto, whiplash injuries can range from minor to more severe damage to muscles and ligaments, which may cause extreme discomfort and require treatment over many months and years. In some cases, total disability may result. The seat belt and shoulder harness can prevent or minimize many other types of collision injuries. But what will protect your [Applause] neck? The rear end collision experiments were designed to study seatback heights and strengths to learn what could be done to minimize whiplash injuries. As motorists, we used instrumented, scientifically designed anthropometric dummies whose body reactions are much like those of human beings. Normal production seatbacks were used in some tests and specially designed seatbacks or added headrests in others. The slowest speed experiment was at 10 mph. [Music] Even at 10 m an hour, the forces are such that trying to resist them [Music] unaded would be like attempting to chin [Music] yourself with another person of your own weight on your back. In this experiment, the driver and front [Music] passenger had seatbacks or headrests 28 in high, they would have felt no serious ill effects. The higher seatbacks prevented whiplash injuries. The rear passengers heads were thrown against the sloping rear glass. [Music] There are many situations in which rear-end collisions occur, often at speeds exceeding 10 [Music] mph. Heat. Heat. [Music] [Music] It is estimated there are 4 million rear end accidents each year in the United States alone. [Music] [Applause] the wrong way. Can't you ever do anything right? Any car with bad brakes is a menace to all involved. It's a perfect setup for rear end collisions. [Music] or near misses like this one finished. Look who's talking. At 30 mph, the forces are similar to those experienced by a Navy pilot launched by [Music] Catapult. The Navy Flyer was protected from such forces. Most motorists are [Music] not. The standard 22-in seatback offered no neck support. The driver, severely whiplashed, was thrown so far back that his eyes were directed out the rear window. A head restraint added to the seat back of the right front passenger helped to prevent whiplash. In another 30 mph crash, the front passenger had a UCLA modified seat 28 in high. This rigid seat back provided good protection from whiplash. The rear passenger's head struck the [Music] window. And while this undoubtedly caused injuries, a whiplash effect was prevented. The highest speed collisions were at 55 [Music] [Music] mph. [Music] [Music] Heat. Heat. [Music] Here, G forces were about double those experienced by astronauts during liftoff. The struck car was knocked 94 ft. Its rear deck collapsed. as did the front end of the striking car. Dyed water simulating fuel exploded over the pavement when the tank [Music] burst. What would have happened if this had been gasoline? Both front seats, 28 in high were forced back, allowing the driver and passenger to be thrown backward. These seats, while a practical height, were not adequately braced to withstand the loadings involved in high-speed collisions. [Music] A seat must be strong enough so that it will not deflect more than 10° even under these extreme [Music] loadings. One rear seat passenger received a whiplash after the rear window was fractured by the crushed trunk lid. The passengers 28 in seatbacks when properly braced to avoid excessive deflection were found to act as motorist brakes. The higher back stops head motion and prevents whiplash. Higher rear seatbacks or a padded shelf are needed to reduce head rotation and chances of injury. Of course, it's still better to avoid a rear ender if you can. Be aware of what is going on around you and to the rear. Be particularly careful of slowdowns or stops. If you see traffic building up ahead, flash your brake lights to warn those behind. Don't end up as a striking car. Pay attention. [Music] To demonstrate the full danger potential of rear-end impacts, the final 55 mph collision was run with gasoline in the struck car's [Music] [Music] tank. Heat. Heat. [Music] [Applause] [Music] a high-speed rear-end collision. can be fatal for all [Music] concerned. You can help avoid one by being attentive and not following too closely. Be alert to what's around you and to the rear. Warn drivers behind you of unexpected stops about to occur. Remember that even low-speed collisions can cause severe whiplash injuries. [Music] In some instances, total disability may result. Take it easy on rain or ice slick [Music] streets. Keep your brakes and tires in stopping condition. Use all the protection you can. Remember that in a rear-end collision, only a high back seat or a head restraint can prevent [Music] whiplash. A good head restraint must be 28 in high. It should be able to withstand static loads of not less than 200 lb. [Music] The framework of an automobile is expendable. Yours is [Music] not. Driving a car is a privilege. It requires your full attention. The business of driving is a full-time job. [Music]