Looking for Data about a Car Accident Injury

November 22, 2021 6:28 PM

My husband and I are having an incredibly pointless recreational dispute (as one does) that has come to hinge on the frequency with which people incur a specific injury in car accidents. Details inside (in case you don't want to see them).

How many people suffer serious injuries to the spine ("severed spine" was the specific injury posited) due to a malpositioned headrest in a car accident? Like, you're too tall for the headrest, it hits you in the neck during the impact, and severs your spinal cord. One of us contends this is VERY COMMON, nay, LIKELY. The other thinks this is complete nonsense and contends this injury must be vanishingly rare.

So we turn to you, MetaFilter, in the hopes of data to prove one of our points, so the winner can lord it over the loser for the foreseeable future and, of course, bring it up every time we get in a car for the rest of eternity.

posted by Eyebrows McGee to Health & Fitness (7 answers total)

He's wrong. ;)

(Also, we can tell he's the one who thinks this is a Thing.)

This article should give you two something to talk about. Looks like headrests are mainly involved in whiplash injuries, not spinal cord injuries.
posted by shadygrove at 6:37 PM on November 22, 2021

Here's a report on hospitalised injuries due to land transport crashes in Australia—it doesn't go granular enough to describe headrest mechanism, but see on Fig. 5 in the PDF, does show the body region injuries that people did get, depending on their mode: neck injuries were much more likely for people in cars than for motorcyclists, pedal cyclists and pedestrians (suggesting there's something about being in a car that makes it dangerous for one's neck, headrest or otherwise); though still, even for car occupants, neck injuries were a minority. Car occupants were most likely to have torso injuries.
posted by Fiasco da Gama at 8:07 PM on November 22, 2021

Your neck has a big ol' unrestrained weight on the end of it while the rest of the body is constrained by seatbelts. This will lead to increased injuries in that area compared to the other three categories. Motorsport participants will often add some sort of head restraint (HANS or similar) to help restrain the head. There is a survivor bias in the numbers too where a pedestrian is probably dead from other injuries if they experience a spinal injury while car occupants are so well protected in modern automobiles that they will often survive a wreck that damages the neck.

Relevant to your discussion it should be noted that while it reduces them a HANS isn't primarily targeted at preventing neck injuries but rather basal skull fractures which technically aren't a spinal fracture.
posted by Mitheral at 8:27 PM on November 22, 2021 [2 favorites]

Here is an analysis and discussion by a specialist in Physical Medicine and Rehabilitation of an incident in the NBA involving Nickola Jokic and Markieff Morris a few weeks ago which bears a striking resemblance to the car accident scenario you describe.

According to Dr. Sutterer

This was the most dangerous play in the NBA this year and in recent memory. Nikola Jokic injured Markieff Morris after hitting him in the back, causing Morris to appear to injure his neck.

It's a lot more serious than it looked or I would have thought, and the typical consequences are far closer on the continuum to "severed spine" than to "complete nonsense and ... vanishingly rare".

Apparently Morris has missed at least 7 games since.
posted by jamjam at 10:23 PM on November 22, 2021

A useful if grim phrase in this discussion is “internal decapitation”. It’s an uncommon injury, but it’s usually fatal and is just kind of horrifying. This article here attributes 8-35% of traffic fatalities to it (via a citation that I didn’t follow up on). We’ve gotten pretty good at preventing traffic deaths, but as Mitheral pointed out, we don’t wear safety gear for this one, aside from the headrest. I can’t speak to how commonly it occurs in cases of badly-adjusted headrests.

This is one of the possible injuries we “hold c-spine” for in traffic accident first aid. I wouldn’t be surprised if the person arguing for it had lost someone to it. They’re not right that it’s likely, but I’ll give partial credit.
posted by hollyholly at 4:45 AM on November 23, 2021

It seems like if this were true (or true-ish) there would be a cottage industry of personal injury lawyers who’d appear in a puff of sulpherous smoke when you Google it! I see only ones mentioning malfunctioning headrests, and not too many of those.

This is maybe not the most scientific approach but it’s not the absolute worst proxy either
posted by chesty_a_arthur at 7:17 AM on November 23, 2021

It's possible that the 8-35% figure in the article posted by hollyholly is out of date, since the cited references fare from the 1970s.

Starting in 1968, The U. S. Department of Transportation (DOT) implemented a requirement that front seats were equipped with headrests to help prevent whiplash. Whiplash can vary in degrees of severity, ranging from Grade 0- "No complaint about the neck. No physical signs" to Grade IV -"Neck complaint and fracture or dislocation."

This article from 1999 concludes, "Even after accounting for differences in driver demographics and crash severity, neck injury rates were significantly lower for drivers of cars with head restraints that were more likely to be behind the heads of motorists."

This (2016) article concludes, "Seats/head restraints with better IIHS ratings are associated with lower injury rates in rear-impact collisions than seats rated poor."

This simulation study , found that a headrest placed at the "optimal level" was associated with a lower value of head injury criterion, compared to headrests that were positioned too low.

This 1993 article concluded that "Improvements in headrest adjustment might help decrease morbidity in motor vehicle accidents."

The TLDR summary... It's a good idea for someone who can get a good fit on the headrest to do so.
posted by oceano at 10:08 AM on November 23, 2021